Rename stack IR to Shid

67 files changed, 867 insertions, 867 deletions

diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenCallTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenCallTests.java
index a802351e..a4ed029f 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenCallTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenCallTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -16,7 +16,7 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenCallTests {
     @Test
     public void canCallFunctionWithNoArgs(Snapshotter snapshotter) throws IOException {
-        var instruction = Instructions.call(0, List.of());
+        var instruction = Shid.call(0, List.of());
         var context = PatioCodeGenContext.EMPTY
             .temporaryPush(new PatioLocalRef("other"))
             .temporaryPush(new PatioLocalRef("receiver"));
@@ -28,7 +28,7 @@ public class PatioCodeGenCallTests {
 
     @Test
     public void canCallFunctionWithArgs(Snapshotter snapshotter) throws IOException {
-        var instruction = Instructions.call(2, List.of("b", "a"));
+        var instruction = Shid.call(2, List.of("b", "a"));
         var context = PatioCodeGenContext.EMPTY
             .temporaryPush(new PatioLocalRef("other"))
             .temporaryPush(new PatioLocalRef("receiver"))
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineEffectTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineEffectTests.java
index a6135d0a..7137affe 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineEffectTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineEffectTests.java
@@ -2,7 +2,7 @@ package org.shedlang.compiler.patio;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 import org.shedlang.compiler.typechecker.TypeInfos;
@@ -17,7 +17,7 @@ public class PatioCodeGenDefineEffectTests {
     @Test
     public void canGenerateCodeForDefineEffect(Snapshotter snapshotter) throws IOException {
         var effect = Effects.userDefined(NamespaceName.of("Example", "Project"), "State");
-        var instruction = Instructions.defineEffect(effect);
+        var instruction = Shid.defineEffect(effect);
         var typeInfos = TypeInfos.EMPTY
             .addUserDefinedEffectInfo(
                 effect,
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineFunctionTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineFunctionTests.java
index 696876b9..b5b9d0b5 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineFunctionTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineFunctionTests.java
@@ -6,8 +6,8 @@ import org.shedlang.compiler.ast.typed.FreeVariables;
 import org.shedlang.compiler.patio.ast.types.PatioTypes;
 import org.shedlang.compiler.patio.instructions.Patio;
 import org.shedlang.compiler.sources.Sources;
-import org.shedlang.compiler.stackir.instructions.DefineFunctionInstruction;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.ShidDefineFunction;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -20,14 +20,14 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenDefineFunctionTests {
     @Test
     public void canDefineMinimalFunction(Snapshotter snapshotter) throws IOException {
-        var instruction = new DefineFunctionInstruction(
+        var instruction = new ShidDefineFunction(
             "f",
             List.of(),
             List.of(),
             FreeVariables.empty(),
             List.of(
-                Instructions.pushUnit(),
-                Instructions.return_()
+                Shid.pushUnit(),
+                Shid.return_()
             ),
             Sources.NULL
         );
@@ -40,20 +40,20 @@ public class PatioCodeGenDefineFunctionTests {
 
     @Test
     public void immutableFreeVariablesAreStoredInAndLoadedFromEnvironment(Snapshotter snapshotter) throws IOException {
-        var instruction = new DefineFunctionInstruction(
+        var instruction = new ShidDefineFunction(
             "f",
             List.of(),
             List.of(),
             FreeVariables.builder().plus("a", Sources.NULL).plus("b", Sources.NULL).build(),
             List.of(
-                Instructions.localLoad("a"),
-                Instructions.return_()
+                Shid.localLoad("a"),
+                Shid.return_()
             ),
             Sources.NULL
         );
         var context = PatioCodeGenContext.EMPTY
-            .defineStackIrParam("a")
-            .defineStackIrParam("b");
+            .defineShidParam("a")
+            .defineShidParam("b");
 
         var result = PatioCodeGen.generateInstruction(instruction, context);
 
@@ -62,20 +62,20 @@ public class PatioCodeGenDefineFunctionTests {
 
     @Test
     public void canCaptureFreeVariablesThatAreSetAfterDefinition(Snapshotter snapshotter) throws IOException {
-        var instruction = new DefineFunctionInstruction(
+        var instruction = new ShidDefineFunction(
             "f",
             List.of(),
             List.of(),
             FreeVariables.builder().plus("a", Sources.NULL).plus("b", Sources.NULL).build(),
             List.of(
-                Instructions.localLoad("a"),
-                Instructions.return_()
+                Shid.localLoad("a"),
+                Shid.return_()
             ),
             Sources.NULL
         );
         var context = PatioCodeGenContext.EMPTY
-            .declareStackIrVal("a", PatioCodeGenTypes.VALUE_TYPE).context()
-            .declareStackIrVal("b", PatioCodeGenTypes.VALUE_TYPE).context();
+            .declareShidVal("a", PatioCodeGenTypes.VALUE_TYPE).context()
+            .declareShidVal("b", PatioCodeGenTypes.VALUE_TYPE).context();
 
         context = PatioCodeGen.generateInstruction(instruction, context);
 
@@ -84,16 +84,16 @@ public class PatioCodeGenDefineFunctionTests {
         // into the closure upon closure creation (i.e. too soon) versus after
         // the free variable is set.
         context = context.addInstruction(Patio.localStore(Patio.localRef("a"), Patio.int_(42)));
-        context = context.initStackIrLocal("a");
+        context = context.initShidLocal("a");
         context = context.addInstruction(Patio.localStore(Patio.localRef("b"), Patio.int_(47)));
-        context = context.initStackIrLocal("b");
+        context = context.initShidLocal("b");
 
         snapshotter.assertSnapshot(serialize(context));
     }
 
     @Test
     public void pointersToFreeMutableVariablesAreStoredInAndLoadedFromEnvironment(Snapshotter snapshotter) throws IOException {
-        var instruction = new DefineFunctionInstruction(
+        var instruction = new ShidDefineFunction(
             "f",
             List.of(),
             List.of(),
@@ -102,16 +102,16 @@ public class PatioCodeGenDefineFunctionTests {
                 .plus("b", Sources.NULL)
                 .build(),
             List.of(
-                Instructions.localLoad("a"),
-                Instructions.return_()
+                Shid.localLoad("a"),
+                Shid.return_()
             ),
             Sources.NULL
         );
         var context = PatioCodeGenContext.EMPTY
-            .declareStackIrVal("a", PatioTypes.DATA_POINTER).context()
-            .initStackIrLocal("a")
-            .declareStackIrVal("b", PatioTypes.DATA_POINTER).context()
-            .initStackIrLocal("b");
+            .declareShidVal("a", PatioTypes.DATA_POINTER).context()
+            .initShidLocal("a")
+            .declareShidVal("b", PatioTypes.DATA_POINTER).context()
+            .initShidLocal("b");
 
         var result = PatioCodeGen.generateInstruction(instruction, context);
 
@@ -120,25 +120,25 @@ public class PatioCodeGenDefineFunctionTests {
 
     @Test
     public void positionalAndNamedParamsAreDefined(Snapshotter snapshotter) throws IOException {
-        var instruction = new DefineFunctionInstruction(
+        var instruction = new ShidDefineFunction(
             "f",
-            List.of(Instructions.param("param1"), Instructions.param("param2")),
+            List.of(Shid.param("param1"), Shid.param("param2")),
             // Define named params in non-lexical order
-            List.of(Instructions.param("paramB"), Instructions.param("paramC"), Instructions.param("paramA")),
+            List.of(Shid.param("paramB"), Shid.param("paramC"), Shid.param("paramA")),
             FreeVariables.builder().plus("a", Sources.NULL).plus("b", Sources.NULL).build(),
             List.of(
-                Instructions.localLoad("a"),
-                Instructions.localLoad("param1"),
-                Instructions.intAdd(),
-                Instructions.localLoad("paramA"),
-                Instructions.intAdd(),
-                Instructions.return_()
+                Shid.localLoad("a"),
+                Shid.localLoad("param1"),
+                Shid.intAdd(),
+                Shid.localLoad("paramA"),
+                Shid.intAdd(),
+                Shid.return_()
             ),
             Sources.NULL
         );
         var context = PatioCodeGenContext.EMPTY
-            .defineStackIrParam("a")
-            .defineStackIrParam("b");
+            .defineShidParam("a")
+            .defineShidParam("b");
 
         var result = PatioCodeGen.generateInstruction(instruction, context);
 
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineStructTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineStructTests.java
index d79a33fd..450dcba2 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineStructTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDefineStructTests.java
@@ -2,7 +2,7 @@ package org.shedlang.compiler.patio;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 import org.shedlang.compiler.typechecker.TypeInfos;
@@ -22,11 +22,11 @@ public class PatioCodeGenDefineStructTests {
     @Test
     public void canGenerateCodeForDefineStruct(Snapshotter snapshotter) throws IOException {
         var structType = Types.struct(NamespaceName.of("Example", "Project"), "User");
-        var instruction = Instructions.defineStruct(
+        var instruction = Shid.defineStruct(
             structType,
             List.of(
-                Instructions.defineStructField("name"),
-                Instructions.defineStructField("isActive")
+                Shid.defineStructField("name"),
+                Shid.defineStructField("isActive")
             )
         );
         var typeInfos = TypeInfos.EMPTY
@@ -51,8 +51,8 @@ public class PatioCodeGenDefineStructTests {
         // will suffice for now
         var structType1 = Types.struct(NamespaceName.of("Example", "Project"), "User");
         var structType2 = Types.struct(NamespaceName.of("Example", "Project"), "Id");
-        var instruction1 = Instructions.defineStruct(structType1, List.of());
-        var instruction2 = Instructions.defineStruct(structType1, List.of());
+        var instruction1 = Shid.defineStruct(structType1, List.of());
+        var instruction2 = Shid.defineStruct(structType1, List.of());
         var typeInfos = TypeInfos.EMPTY
             .addStructTypeInfo(structType1, StructTypeInfo.builder().build())
             .addStructTypeInfo(structType2, StructTypeInfo.builder().build());
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDiscardTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDiscardTests.java
index da7e55de..ff66e6bb 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDiscardTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenDiscardTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,12 +15,12 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenDiscardTests {
     @Test
     public void discardInstructionPopsFromTemporaryStack(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.discard();
+        var shid = Shid.discard();
         var context = PatioCodeGenContext.EMPTY
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenFieldLoadTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenFieldLoadTests.java
index 1b313b84..24ec9c18 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenFieldLoadTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenFieldLoadTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 import org.shedlang.compiler.typechecker.TypeCheckerContext;
@@ -20,7 +20,7 @@ public class PatioCodeGenFieldLoadTests {
     @Test
     public void canGenerateCodeForNamespaceFieldLoad(Snapshotter snapshotter) throws IOException {
         var namespaceName = new NamespaceName(List.of("Example", "Project"));
-        var stackIrInstruction = Instructions.fieldLoad(namespaceName, "y");
+        var shidInstruction = Shid.fieldLoad(namespaceName, "y");
         var typeInfos = TypeCheckerContext.EMPTY
             .addNamespaceTypeInfo(
                 namespaceName,
@@ -35,7 +35,7 @@ public class PatioCodeGenFieldLoadTests {
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"));
 
-        var result = PatioCodeGen.generateInstruction(stackIrInstruction, context);
+        var result = PatioCodeGen.generateInstruction(shidInstruction, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
@@ -44,7 +44,7 @@ public class PatioCodeGenFieldLoadTests {
     public void canGenerateCodeForStructFieldLoad(Snapshotter snapshotter) throws IOException {
         var namespaceName = NamespaceName.of("Example", "Project");
         var structType = Types.struct(namespaceName, "User");
-        var stackIrInstruction = Instructions.fieldLoad(structType, "id");
+        var shidInstruction = Shid.fieldLoad(structType, "id");
         var typeInfos = TypeInfos.EMPTY
             .addStructTypeInfo(
                 structType,
@@ -58,7 +58,7 @@ public class PatioCodeGenFieldLoadTests {
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"));
 
-        var result = PatioCodeGen.generateInstruction(stackIrInstruction, context);
+        var result = PatioCodeGen.generateInstruction(shidInstruction, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
@@ -67,7 +67,7 @@ public class PatioCodeGenFieldLoadTests {
     public void canGenerateCodeForUserDefinedEffectFieldLoad(Snapshotter snapshotter) throws IOException {
         var namespaceName = NamespaceName.of("Example", "Project");
         var effect = Effects.userDefined(namespaceName, "State");
-        var stackIrInstruction = Instructions.fieldLoad(effect, "fence");
+        var shidInstruction = Shid.fieldLoad(effect, "fence");
         var typeInfos = TypeInfos.EMPTY
             .addUserDefinedEffectInfo(
                 effect,
@@ -81,7 +81,7 @@ public class PatioCodeGenFieldLoadTests {
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"));
 
-        var result = PatioCodeGen.generateInstruction(stackIrInstruction, context);
+        var result = PatioCodeGen.generateInstruction(shidInstruction, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIfTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIfTests.java
index c06f0c5e..34edd733 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIfTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIfTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -16,15 +16,15 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenIfTests {
     @Test
     public void canGenerateCodeForIfWithNoResults(Snapshotter snapshotter) throws IOException {
-        var instruction = Instructions.if_(
+        var instruction = Shid.if_(
             0,
             List.of(
-                Instructions.pushInt(1),
-                Instructions.discard()
+                Shid.pushInt(1),
+                Shid.discard()
             ),
             List.of(
-                Instructions.pushInt(101),
-                Instructions.discard()
+                Shid.pushInt(101),
+                Shid.discard()
             )
         );
         var context = PatioCodeGenContext.EMPTY
@@ -38,17 +38,17 @@ public class PatioCodeGenIfTests {
 
     @Test
     public void canGenerateCodeForIfWithSingleResult(Snapshotter snapshotter) throws IOException {
-        var instruction = Instructions.if_(
+        var instruction = Shid.if_(
             1,
             List.of(
-                Instructions.pushInt(1),
-                Instructions.pushInt(2),
-                Instructions.intAdd()
+                Shid.pushInt(1),
+                Shid.pushInt(2),
+                Shid.intAdd()
             ),
             List.of(
-                Instructions.pushInt(101),
-                Instructions.pushInt(102),
-                Instructions.intAdd()
+                Shid.pushInt(101),
+                Shid.pushInt(102),
+                Shid.intAdd()
             )
         );
         var context = PatioCodeGenContext.EMPTY
@@ -62,15 +62,15 @@ public class PatioCodeGenIfTests {
 
     @Test
     public void canGenerateCodeForIfWithMultipleResults(Snapshotter snapshotter) throws IOException {
-        var instruction = Instructions.if_(
+        var instruction = Shid.if_(
             2,
             List.of(
-                Instructions.pushInt(1),
-                Instructions.pushInt(2)
+                Shid.pushInt(1),
+                Shid.pushInt(2)
             ),
             List.of(
-                Instructions.pushInt(101),
-                Instructions.pushInt(102)
+                Shid.pushInt(101),
+                Shid.pushInt(102)
             )
         );
         var context = PatioCodeGenContext.EMPTY
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntAddTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntAddTests.java
index 12016446..53158d0d 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntAddTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntAddTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,13 +15,13 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenIntAddTests {
     @Test
     public void canGenerateCodeForIntAdd(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.intAdd();
+        var shid = Shid.intAdd();
         var context = PatioCodeGenContext.EMPTY
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"))
             .temporaryPush(new PatioLocalRef("c"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntEqualsTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntEqualsTests.java
index cc1eaf2d..8b9fe35f 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntEqualsTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntEqualsTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,13 +15,13 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenIntEqualsTests {
     @Test
     public void canGenerateCodeForIntEquals(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.intEquals();
+        var shid = Shid.intEquals();
         var context = PatioCodeGenContext.EMPTY
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"))
             .temporaryPush(new PatioLocalRef("c"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntNotEqualTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntNotEqualTests.java
index 253781d3..5715f0d4 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntNotEqualTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntNotEqualTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,13 +15,13 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenIntNotEqualTests {
     @Test
     public void canGenerateCodeForIntNotEqual(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.intNotEqual();
+        var shid = Shid.intNotEqual();
         var context = PatioCodeGenContext.EMPTY
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"))
             .temporaryPush(new PatioLocalRef("c"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntSubTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntSubTests.java
index 9c0ccae9..e2036764 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntSubTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenIntSubTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,13 +15,13 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenIntSubTests {
     @Test
     public void canGenerateCodeForIntSub(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.intSub();
+        var shid = Shid.intSub();
         var context = PatioCodeGenContext.EMPTY
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"))
             .temporaryPush(new PatioLocalRef("c"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLocalLoadTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLocalLoadTests.java
index 7e6b5705..f452583b 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLocalLoadTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLocalLoadTests.java
@@ -2,7 +2,7 @@ package org.shedlang.compiler.patio;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -14,11 +14,11 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenLocalLoadTests {
     @Test
     public void localLoadPushesLocalOntoStack(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.localLoad("x");
+        var shid = Shid.localLoad("x");
         var context = PatioCodeGenContext.EMPTY
-            .defineStackIrParam("x");
+            .defineShidParam("x");
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLocalStoreTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLocalStoreTests.java
index dd37b35f..00b50c44 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLocalStoreTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLocalStoreTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,13 +15,13 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenLocalStoreTests {
     @Test
     public void localStorePopsTemporaryIntoLocal(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.localStore("x");
+        var shid = Shid.localStore("x");
         var context = PatioCodeGenContext.EMPTY
-            .declareStackIrVal("x", PatioCodeGenTypes.VALUE_TYPE).context()
+            .declareShidVal("x", PatioCodeGenTypes.VALUE_TYPE).context()
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLoopBreakTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLoopBreakTests.java
index 76a3799c..16ab525d 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLoopBreakTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLoopBreakTests.java
@@ -2,7 +2,7 @@ package org.shedlang.compiler.patio;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -14,7 +14,7 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenLoopBreakTests {
     @Test
     public void canGenerateCodeForLoopBreak(Snapshotter snapshotter) throws IOException {
-        var instruction = Instructions.loopBreak();
+        var instruction = Shid.loopBreak();
         var context = PatioCodeGenContext.EMPTY;
 
         var result = PatioCodeGen.generateInstruction(instruction, context);
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLoopContinueTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLoopContinueTests.java
index 281f6dcd..0e9372fc 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLoopContinueTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLoopContinueTests.java
@@ -2,7 +2,7 @@ package org.shedlang.compiler.patio;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -14,7 +14,7 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenLoopContinueTests {
     @Test
     public void canGenerateCodeForLoopContinue(Snapshotter snapshotter) throws IOException {
-        var instruction = Instructions.loopContinue();
+        var instruction = Shid.loopContinue();
         var context = PatioCodeGenContext.EMPTY;
 
         var result = PatioCodeGen.generateInstruction(instruction, context);
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLoopTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLoopTests.java
index ff74a17b..6a9648db 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLoopTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenLoopTests.java
@@ -2,7 +2,7 @@ package org.shedlang.compiler.patio;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,10 +15,10 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenLoopTests {
     @Test
     public void canGenerateCodeForLoop(Snapshotter snapshotter) throws IOException {
-        var instruction = Instructions.loop(
+        var instruction = Shid.loop(
             List.of(
-                Instructions.pushInt(1),
-                Instructions.discard()
+                Shid.pushInt(1),
+                Shid.discard()
             )
         );
         var context = PatioCodeGenContext.EMPTY;
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenNamespaceFieldStoreTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenNamespaceFieldStoreTests.java
index c905d0ce..254249e0 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenNamespaceFieldStoreTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenNamespaceFieldStoreTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 import org.shedlang.compiler.typechecker.TypeCheckerContext;
@@ -21,7 +21,7 @@ public class PatioCodeGenNamespaceFieldStoreTests {
     @Test
     public void canGenerateCodeForNamespaceFieldStore(Snapshotter snapshotter) throws IOException {
         var namespaceName = new NamespaceName(List.of("Example", "Project"));
-        var stackIrInstruction = Instructions.namespaceFieldStore(namespaceName, "y");
+        var shidInstruction = Shid.namespaceFieldStore(namespaceName, "y");
         var typeInfo = TypeCheckerContext.EMPTY
             .addNamespaceTypeInfo(
                 namespaceName,
@@ -36,7 +36,7 @@ public class PatioCodeGenNamespaceFieldStoreTests {
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"));
 
-        var result = PatioCodeGen.generateInstruction(stackIrInstruction, context);
+        var result = PatioCodeGen.generateInstruction(shidInstruction, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenNamespaceImportTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenNamespaceImportTests.java
index 705e90dc..f86388cb 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenNamespaceImportTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenNamespaceImportTests.java
@@ -2,7 +2,7 @@ package org.shedlang.compiler.patio;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 import org.shedlang.compiler.types.NamespaceName;
@@ -17,7 +17,7 @@ public class PatioCodeGenNamespaceImportTests {
     @Test
     public void canGenerateCodeForNamespaceImport(Snapshotter snapshotter) throws IOException {
         var namespaceName = new NamespaceName(List.of("Example", "Project"));
-        var instruction = Instructions.namespaceImport(namespaceName);
+        var instruction = Shid.namespaceImport(namespaceName);
         var context = PatioCodeGenContext.EMPTY;
 
         var result = PatioCodeGen.generateInstruction(instruction, context);
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenNamespaceTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenNamespaceTests.java
index 2a3154ef..852eda6f 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenNamespaceTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenNamespaceTests.java
@@ -4,10 +4,10 @@ import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.ast.typed.FreeVariables;
 import org.shedlang.compiler.sources.Sources;
-import org.shedlang.compiler.stackir.StackIrNamespace;
-import org.shedlang.compiler.stackir.instructions.DefineFunctionInstruction;
-import org.shedlang.compiler.stackir.instructions.Instruction;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.ShidNamespace;
+import org.shedlang.compiler.shid.instructions.ShidDefineFunction;
+import org.shedlang.compiler.shid.instructions.ShidInstruction;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 import org.shedlang.compiler.typechecker.TypeInfos;
@@ -24,18 +24,18 @@ import static org.shedlang.compiler.patio.PatioTesting.serializeCompilationUnit;
 public class PatioCodeGenNamespaceTests {
     @Test
     public void canDefineNamespace(Snapshotter snapshotter) throws IOException {
-        var instruction = new DefineFunctionInstruction(
+        var instruction = new ShidDefineFunction(
             "f",
             List.of(),
             List.of(),
             FreeVariables.empty(),
             List.of(
-                Instructions.pushUnit(),
-                Instructions.return_()
+                Shid.pushUnit(),
+                Shid.return_()
             ),
             Sources.NULL
         );
-        var instructions = List.<Instruction>of(instruction);
+        var instructions = List.<ShidInstruction>of(instruction);
         var namespaceName = NamespaceName.of("An","Example");
         var typeInfos = TypeInfos.EMPTY
             .addNamespaceTypeInfo(
@@ -46,9 +46,9 @@ public class PatioCodeGenNamespaceTests {
                     .build()
             );
         var context = PatioCodeGenContext.forTypeInfos(typeInfos);
-        var stackIrNamespace = new StackIrNamespace(namespaceName, instructions);
+        var shidNamespace = new ShidNamespace(namespaceName, instructions);
 
-        var result = PatioCodeGen.generateNamespace(stackIrNamespace, context);
+        var result = PatioCodeGen.generateNamespace(shidNamespace, context);
 
         snapshotter.assertSnapshot(serializeCompilationUnit(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushBoolTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushBoolTests.java
index 8045decf..4b3c869c 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushBoolTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushBoolTests.java
@@ -2,7 +2,7 @@ package org.shedlang.compiler.patio;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -14,20 +14,20 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenPushBoolTests {
     @Test
     public void pushBoolFalseInstructionGeneratesIntGetZeroInstruction(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.pushBool(false);
+        var shid = Shid.pushBool(false);
         var context = PatioCodeGenContext.EMPTY;
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
 
     @Test
     public void pushBoolTrueInstructionGeneratesIntGetOneInstruction(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.pushBool(true);
+        var shid = Shid.pushBool(true);
         var context = PatioCodeGenContext.EMPTY;
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushIntTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushIntTests.java
index b1790fda..0996f981 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushIntTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushIntTests.java
@@ -2,7 +2,7 @@ package org.shedlang.compiler.patio;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -14,10 +14,10 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenPushIntTests {
     @Test
     public void pushIntInstructionGeneratesIntGetInstruction(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.pushInt(42);
+        var shid = Shid.pushInt(42);
         var context = PatioCodeGenContext.EMPTY;
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushStringTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushStringTests.java
index 28989deb..3a878afe 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushStringTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushStringTests.java
@@ -2,7 +2,7 @@ package org.shedlang.compiler.patio;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -14,10 +14,10 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenPushStringTests {
     @Test
     public void pushStringIsCompiledToDataAndIndexToData(Snapshotter snapshotter) throws IOException {
-        var stackIrInstruction = Instructions.pushString("hello");
+        var shidInstruction = Shid.pushString("hello");
         var context = PatioCodeGenContext.EMPTY;
 
-        var result = PatioCodeGen.generateInstruction(stackIrInstruction, context);
+        var result = PatioCodeGen.generateInstruction(shidInstruction, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
@@ -26,8 +26,8 @@ public class PatioCodeGenPushStringTests {
     public void canHaveMultipleStrings(Snapshotter snapshotter) throws IOException {
         var context = PatioCodeGenContext.EMPTY;
 
-        var result = PatioCodeGen.generateInstruction(Instructions.pushString("hello"), context);
-        result = PatioCodeGen.generateInstruction(Instructions.pushString("world"), result);
+        var result = PatioCodeGen.generateInstruction(Shid.pushString("hello"), context);
+        result = PatioCodeGen.generateInstruction(Shid.pushString("world"), result);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushUnitTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushUnitTests.java
index 3aec3619..d1aa4bd8 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushUnitTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenPushUnitTests.java
@@ -2,7 +2,7 @@ package org.shedlang.compiler.patio;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -14,10 +14,10 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenPushUnitTests {
     @Test
     public void pushUnitInstructionGeneratesIntGetInstruction(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.pushUnit();
+        var shid = Shid.pushUnit();
         var context = PatioCodeGenContext.EMPTY;
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenResumeTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenResumeTests.java
index 5f23b926..57d16015 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenResumeTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenResumeTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,12 +15,12 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenResumeTests {
     @Test
     public void resumeInstructionGeneratesResumeInstruction(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.resume();
+        var shid = Shid.resume();
         var context = PatioCodeGenContext.EMPTY
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenReturnTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenReturnTests.java
index 760f23e8..9a7166c5 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenReturnTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenReturnTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,12 +15,12 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenReturnTests {
     @Test
     public void returnInstructionGeneratesReturnInstruction(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.return_();
+        var shid = Shid.return_();
         var context = PatioCodeGenContext.EMPTY
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenStringAddTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenStringAddTests.java
index 0ff8dade..8eb09cb7 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenStringAddTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenStringAddTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,13 +15,13 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenStringAddTests {
     @Test
     public void canGenerateCodeForStringAdd(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.stringAdd();
+        var shid = Shid.stringAdd();
         var context = PatioCodeGenContext.EMPTY
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"))
             .temporaryPush(new PatioLocalRef("c"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenSwitchTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenSwitchTests.java
index 979743e3..58463cb4 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenSwitchTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenSwitchTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 import org.shedlang.compiler.typechecker.TypeInfos;
@@ -23,22 +23,22 @@ public class PatioCodeGenSwitchTests {
         var namespaceName = NamespaceName.of("Example", "Project");
         var structType1 = Types.struct(namespaceName, "A");
         var structType2 = Types.struct(namespaceName, "B");
-        var instruction = Instructions.switch_(
+        var instruction = Shid.switch_(
             List.of(
-                Instructions.switchCase(
+                Shid.switchCase(
                     structType1,
                     List.of(
-                        Instructions.pushInt(1),
-                        Instructions.pushInt(2),
-                        Instructions.intAdd()
+                        Shid.pushInt(1),
+                        Shid.pushInt(2),
+                        Shid.intAdd()
                     )
                 ),
-                Instructions.switchCase(
+                Shid.switchCase(
                     structType2,
                     List.of(
-                        Instructions.pushInt(101),
-                        Instructions.pushInt(102),
-                        Instructions.intAdd()
+                        Shid.pushInt(101),
+                        Shid.pushInt(102),
+                        Shid.intAdd()
                     )
                 )
             )
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenTryTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenTryTests.java
index 1a9535d1..f534534c 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenTryTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenTryTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 import org.shedlang.compiler.typechecker.TypeCheckerContext;
@@ -20,11 +20,11 @@ public class PatioCodeGenTryTests {
     public void canGenerateCodeForTry(Snapshotter snapshotter) throws IOException {
         var namespaceName = new NamespaceName(List.of("Example", "Project"));
         var effect = Effects.userDefined(namespaceName, "State");
-        var stackIrInstruction = Instructions.try_(
+        var shidInstruction = Shid.try_(
             effect,
             List.of("a", "c", "b"),
             List.of(
-                Instructions.pushInt(42)
+                Shid.pushInt(42)
             )
         );
         var typeInfos = TypeCheckerContext.EMPTY
@@ -43,7 +43,7 @@ public class PatioCodeGenTryTests {
             .temporaryPush(new PatioLocalRef("handlerC"))
             .temporaryPush(new PatioLocalRef("handlerB"));
 
-        var result = PatioCodeGen.generateInstruction(stackIrInstruction, context);
+        var result = PatioCodeGen.generateInstruction(shidInstruction, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenTupleCreateTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenTupleCreateTests.java
index e489fb37..d5cb6ef1 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenTupleCreateTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenTupleCreateTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,24 +15,24 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenTupleCreateTests {
     @Test
     public void canGenerateCodeForTupleCreate(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.tupleCreate(3);
+        var shid = Shid.tupleCreate(3);
         var context = PatioCodeGenContext.EMPTY
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"))
             .temporaryPush(new PatioLocalRef("c"))
             .temporaryPush(new PatioLocalRef("d"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
 
     @Test
     public void zeroElementTupleIsCreatedWithoutAlloc(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.tupleCreate(0);
+        var shid = Shid.tupleCreate(0);
         var context = PatioCodeGenContext.EMPTY;
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenTupleGetTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenTupleGetTests.java
index fc1cf272..41a037b0 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenTupleGetTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenTupleGetTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,12 +15,12 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenTupleGetTests {
     @Test
     public void canGenerateCodeForTupleGet(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.tupleGet(2, 3);
+        var shid = Shid.tupleGet(2, 3);
         var context = PatioCodeGenContext.EMPTY
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenVarLoadTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenVarLoadTests.java
index 4cff0dd4..3eae5cf9 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenVarLoadTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenVarLoadTests.java
@@ -3,7 +3,7 @@ package org.shedlang.compiler.patio;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.types.PatioTypes;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -15,11 +15,11 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenVarLoadTests {
     @Test
     public void canGenerateCodeForVarLoad(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.varLoad("x");
+        var shid = Shid.varLoad("x");
         var context = PatioCodeGenContext.EMPTY
-            .declareStackIrVal("x", PatioTypes.DATA_POINTER).context();
+            .declareShidVal("x", PatioTypes.DATA_POINTER).context();
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenVarStoreTests.java b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenVarStoreTests.java
index 66038785..4f9d4430 100644
--- a/src/test/java/org/shedlang/compiler/patio/PatioCodeGenVarStoreTests.java
+++ b/src/test/java/org/shedlang/compiler/patio/PatioCodeGenVarStoreTests.java
@@ -4,7 +4,7 @@ import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.shedlang.compiler.patio.ast.operands.PatioLocalRef;
 import org.shedlang.compiler.patio.ast.types.PatioTypes;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.testing.snapshots.SnapshotResolver;
 import org.shedlang.compiler.testing.snapshots.Snapshotter;
 
@@ -16,27 +16,27 @@ import static org.shedlang.compiler.patio.PatioTesting.serialize;
 public class PatioCodeGenVarStoreTests {
     @Test
     public void canGenerateCodeForVarStore(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.varStore("x");
+        var shid = Shid.varStore("x");
         var context = PatioCodeGenContext.EMPTY
-            .declareStackIrVal("x", PatioTypes.DATA_POINTER).context()
+            .declareShidVal("x", PatioTypes.DATA_POINTER).context()
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
+        var result = PatioCodeGen.generateInstruction(shid, context);
 
         snapshotter.assertSnapshot(serialize(result));
     }
 
     @Test
     public void canStoreIntoVarMultipleTimes(Snapshotter snapshotter) throws IOException {
-        var stackIr = Instructions.varStore("x");
+        var shid = Shid.varStore("x");
         var context = PatioCodeGenContext.EMPTY
-            .declareStackIrVal("x", PatioTypes.DATA_POINTER).context()
+            .declareShidVal("x", PatioTypes.DATA_POINTER).context()
             .temporaryPush(new PatioLocalRef("a"))
             .temporaryPush(new PatioLocalRef("b"));
 
-        var result = PatioCodeGen.generateInstruction(stackIr, context);
-        result = PatioCodeGen.generateInstruction(stackIr, result);
+        var result = PatioCodeGen.generateInstruction(shid, context);
+        result = PatioCodeGen.generateInstruction(shid, result);
 
         snapshotter.assertSnapshot(serialize(result));
     }
diff --git a/src/test/java/org/shedlang/compiler/stackir/InstructionSerializerTests.java b/src/test/java/org/shedlang/compiler/shid/InstructionSerializerTests.java
index c36977cf..9f6bdcf1 100644
--- a/src/test/java/org/shedlang/compiler/stackir/InstructionSerializerTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/InstructionSerializerTests.java
@@ -1,9 +1,9 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
-import org.shedlang.compiler.stackir.instructions.DefineFunctionInstruction;
-import org.shedlang.compiler.stackir.instructions.Instruction;
-import org.shedlang.compiler.stackir.instructions.Instructions;
+import org.shedlang.compiler.shid.instructions.ShidDefineFunction;
+import org.shedlang.compiler.shid.instructions.ShidInstruction;
+import org.shedlang.compiler.shid.instructions.Shid;
 import org.shedlang.compiler.types.Effects;
 import org.shedlang.compiler.types.NamespaceName;
 import org.shedlang.compiler.types.Types;
@@ -16,7 +16,7 @@ import static org.zwobble.precisely.Matchers.equalTo;
 public class InstructionSerializerTests {
     @Test
     public void canSerializeCall() {
-        var instruction = Instructions.call(1, List.of("x", "y"));
+        var instruction = Shid.call(1, List.of("x", "y"));
 
         var string = serialize(instruction);
 
@@ -25,7 +25,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeDefineEffect() {
-        var instruction = Instructions.defineEffect(
+        var instruction = Shid.defineEffect(
             Effects.userDefined(NamespaceName.of("Example", "Project"), "State")
         );
 
@@ -38,7 +38,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeDefineFunction() {
-        var instruction = DefineFunctionInstruction.builder()
+        var instruction = ShidDefineFunction.builder()
             .withName("f")
             .addPositionalParam("p1")
             .addPositionalParam("p2")
@@ -46,8 +46,8 @@ public class InstructionSerializerTests {
             .addNamedParam("n2")
             .addFreeVariable("fv1")
             .addFreeVariable("fv2")
-            .addBodyInstruction(Instructions.pushBool(true))
-            .addBodyInstruction(Instructions.pushBool(false))
+            .addBodyInstruction(Shid.pushBool(true))
+            .addBodyInstruction(Shid.pushBool(false))
             .build();
 
         var string = serialize(instruction);
@@ -68,11 +68,11 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeDefineStruct() {
-        var instruction = Instructions.defineStruct(
+        var instruction = Shid.defineStruct(
             Types.struct(NamespaceName.of("Example", "Project"), "User"),
             List.of(
-                Instructions.defineStructField("name"),
-                Instructions.defineStructField("id")
+                Shid.defineStructField("name"),
+                Shid.defineStructField("id")
             )
         );
 
@@ -88,7 +88,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeDiscard() {
-        var instruction = Instructions.discard();
+        var instruction = Shid.discard();
 
         var string = serialize(instruction);
 
@@ -97,7 +97,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeDuplicate() {
-        var instruction = Instructions.duplicate();
+        var instruction = Shid.duplicate();
 
         var string = serialize(instruction);
 
@@ -106,7 +106,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeNamespaceFieldLoad() {
-        var instruction = Instructions.fieldLoad(
+        var instruction = Shid.fieldLoad(
             new NamespaceName(List.of("Example", "Lib")),
             "x"
         );
@@ -118,7 +118,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeStructFieldLoad() {
-        var instruction = Instructions.fieldLoad(
+        var instruction = Shid.fieldLoad(
             Types.struct(NamespaceName.of("Example", "Project"), "User"),
             "name"
         );
@@ -130,7 +130,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeUserDefinedEffectFieldLoad() {
-        var instruction = Instructions.fieldLoad(
+        var instruction = Shid.fieldLoad(
             Effects.userDefined(NamespaceName.of("Example", "Project"), "State"),
             "read"
         );
@@ -142,15 +142,15 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeIf() {
-        var instruction = Instructions.if_(
+        var instruction = Shid.if_(
             1,
             List.of(
-                Instructions.pushUnit()
+                Shid.pushUnit()
             ),
             List.of(
-                Instructions.localLoad("x"),
-                Instructions.discard(),
-                Instructions.pushBool(true)
+                Shid.localLoad("x"),
+                Shid.discard(),
+                Shid.pushBool(true)
             )
         );
 
@@ -173,7 +173,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeIntAdd() {
-        var instruction = Instructions.intAdd();
+        var instruction = Shid.intAdd();
 
         var string = serialize(instruction);
 
@@ -182,7 +182,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeIntEquals() {
-        var instruction = Instructions.intEquals();
+        var instruction = Shid.intEquals();
 
         var string = serialize(instruction);
 
@@ -191,7 +191,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeIntNotEqual() {
-        var instruction = Instructions.intNotEqual();
+        var instruction = Shid.intNotEqual();
 
         var string = serialize(instruction);
 
@@ -200,7 +200,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeIntSub() {
-        var instruction = Instructions.intSub();
+        var instruction = Shid.intSub();
 
         var string = serialize(instruction);
 
@@ -209,7 +209,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeLocalLoad() {
-        var instruction = Instructions.localLoad("x");
+        var instruction = Shid.localLoad("x");
 
         var string = serialize(instruction);
 
@@ -218,7 +218,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeLocalStore() {
-        var instruction = Instructions.localStore("x");
+        var instruction = Shid.localStore("x");
 
         var string = serialize(instruction);
 
@@ -227,10 +227,10 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeLoop() {
-        var instruction = Instructions.loop(
+        var instruction = Shid.loop(
             List.of(
-                Instructions.localLoad("x"),
-                Instructions.discard()
+                Shid.localLoad("x"),
+                Shid.discard()
             )
         );
 
@@ -248,7 +248,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeLoopBreak() {
-        var instruction = Instructions.loopBreak();
+        var instruction = Shid.loopBreak();
 
         var string = serialize(instruction);
 
@@ -257,7 +257,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeLoopContinue() {
-        var instruction = Instructions.loopContinue();
+        var instruction = Shid.loopContinue();
 
         var string = serialize(instruction);
 
@@ -266,7 +266,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeNamespaceFieldStore() {
-        var instruction = Instructions.namespaceFieldStore(
+        var instruction = Shid.namespaceFieldStore(
             new NamespaceName(List.of("Example", "Lib")),
             "x"
         );
@@ -278,7 +278,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeNamespaceImport() {
-        var instruction = Instructions.namespaceImport(
+        var instruction = Shid.namespaceImport(
             new NamespaceName(List.of("Example", "Lib"))
         );
 
@@ -289,7 +289,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializePushBool() {
-        var instruction = Instructions.pushBool(true);
+        var instruction = Shid.pushBool(true);
 
         var string = serialize(instruction);
 
@@ -298,7 +298,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializePushInt() {
-        var instruction = Instructions.pushInt(42);
+        var instruction = Shid.pushInt(42);
 
         var string = serialize(instruction);
 
@@ -307,7 +307,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializePushString() {
-        var instruction = Instructions.pushString("hello");
+        var instruction = Shid.pushString("hello");
 
         var string = serialize(instruction);
 
@@ -316,7 +316,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void specialCharactersInStringAreEscaped() {
-        var instruction = Instructions.pushString("\b\t\n\f\r\"\\");
+        var instruction = Shid.pushString("\b\t\n\f\r\"\\");
 
         var string = serialize(instruction);
 
@@ -325,7 +325,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializePushUnit() {
-        var instruction = Instructions.pushUnit();
+        var instruction = Shid.pushUnit();
 
         var string = serialize(instruction);
 
@@ -334,7 +334,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeResume() {
-        var instruction = Instructions.resume();
+        var instruction = Shid.resume();
 
         var string = serialize(instruction);
 
@@ -343,7 +343,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeReturn() {
-        var instruction = Instructions.return_();
+        var instruction = Shid.return_();
 
         var string = serialize(instruction);
 
@@ -352,7 +352,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeStringAdd() {
-        var instruction = Instructions.stringAdd();
+        var instruction = Shid.stringAdd();
 
         var string = serialize(instruction);
 
@@ -361,17 +361,17 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeSwitch() {
-        var instruction = Instructions.switch_(List.of(
-            Instructions.switchCase(
+        var instruction = Shid.switch_(List.of(
+            Shid.switchCase(
                 Types.struct(NamespaceName.of("Example", "Project"), "A"),
                 List.of(
-                    Instructions.return_()
+                    Shid.return_()
                 )
             ),
-            Instructions.switchCase(
+            Shid.switchCase(
                 Types.struct(NamespaceName.of("Example", "Project"), "B"),
                 List.of(
-                    Instructions.discard()
+                    Shid.discard()
                 )
             )
         ));
@@ -401,11 +401,11 @@ public class InstructionSerializerTests {
     @Test
     public void canSerializeTry() {
         var effect = Effects.userDefined(NamespaceName.of("Example", "Project"), "State");
-        var instruction = Instructions.try_(
+        var instruction = Shid.try_(
             effect,
             List.of("read", "write"),
             List.of(
-                Instructions.pushUnit()
+                Shid.pushUnit()
             )
         );
 
@@ -427,7 +427,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeTupleCreate() {
-        var instruction = Instructions.tupleCreate(2);
+        var instruction = Shid.tupleCreate(2);
 
         var string = serialize(instruction);
 
@@ -436,7 +436,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeTupleGet() {
-        var instruction = Instructions.tupleGet(2, 3);
+        var instruction = Shid.tupleGet(2, 3);
 
         var string = serialize(instruction);
 
@@ -445,7 +445,7 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeVarLoad() {
-        var instruction = Instructions.varLoad("x");
+        var instruction = Shid.varLoad("x");
 
         var string = serialize(instruction);
 
@@ -454,14 +454,14 @@ public class InstructionSerializerTests {
 
     @Test
     public void canSerializeVarStore() {
-        var instruction = Instructions.varStore("x");
+        var instruction = Shid.varStore("x");
 
         var string = serialize(instruction);
 
         assertThat(string, equalTo("(var-store \"x\")"));
     }
 
-    private String serialize(Instruction instruction) {
+    private String serialize(ShidInstruction instruction) {
         var builder = new StringBuilder();
         InstructionSerializer.serializeInstruction(instruction, builder);
         return builder.toString();
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerAssignTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenAssignTests.java
index 431556a0..65e30e5a 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerAssignTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenAssignTests.java
@@ -1,25 +1,25 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
 import java.util.List;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerAssignTests {
+public class ShidCodeGenAssignTests {
     @Test
     public void targetIgnoreIsCompiledToDiscard() {
         var node = Typed.assign(
             Typed.targetIgnore(),
             Typed.reference("x")
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("x");
 
-        var result = StackCompiler.compileFunctionStatement(node, context);
+        var result = ShidCodeGen.compileFunctionStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLocalLoadInstruction("x__0"),
@@ -33,10 +33,10 @@ public class StackCompilerAssignTests {
             Typed.targetReassign("x"),
             Typed.stringLiteral("hello")
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("x");
 
-        var result = StackCompiler.compileFunctionStatement(node, context);
+        var result = ShidCodeGen.compileFunctionStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushStringInstruction("hello"),
@@ -54,13 +54,13 @@ public class StackCompilerAssignTests {
             )),
             Typed.reference("x")
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("x")
             .addShedVal("a")
             .addShedVal("b")
             .addShedVal("c");
 
-        var result = StackCompiler.compileFunctionStatement(node, context);
+        var result = ShidCodeGen.compileFunctionStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLocalLoadInstruction("x__0"),
@@ -81,10 +81,10 @@ public class StackCompilerAssignTests {
             Typed.targetTuple(List.of()),
             Typed.reference("x")
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("x");
 
-        var result = StackCompiler.compileFunctionStatement(node, context);
+        var result = ShidCodeGen.compileFunctionStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLocalLoadInstruction("x__0"),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerBlockReturnTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenBlockReturnTests.java
index df738405..082560b7 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerBlockReturnTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenBlockReturnTests.java
@@ -1,19 +1,19 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isPushStringInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isPushStringInstruction;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerBlockReturnTests {
+public class ShidCodeGenBlockReturnTests {
     @Test
     public void expressionIsEvaluated() {
         var node = Typed.blockReturn(Typed.stringLiteral("hello"));
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileFunctionStatement(node, context);
+        var result = ShidCodeGen.compileFunctionStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushStringInstruction("hello")
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerBoolLiteralTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenBoolLiteralTests.java
index ac96c48e..965f9b3c 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerBoolLiteralTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenBoolLiteralTests.java
@@ -1,19 +1,19 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isPushBoolInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isPushBoolInstruction;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerBoolLiteralTests {
+public class ShidCodeGenBoolLiteralTests {
     @Test
     public void boolLiteralIsCompiledToPushBoolInstruction() {
         var node = Typed.boolLiteral(true);
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushBoolInstruction(true)
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerCallTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenCallTests.java
index 2cf25bb1..5d14cc31 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerCallTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenCallTests.java
@@ -1,15 +1,15 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
 import java.util.List;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerCallTests {
+public class ShidCodeGenCallTests {
     @Test
     public void callIsCompiledToInstructionsForOperandThenCall() {
         var node = Typed.call(
@@ -24,10 +24,10 @@ public class StackCompilerCallTests {
                 Typed.namedArg("x1", Typed.stringLiteral("n1"))
             )
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("f");
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLocalLoadInstruction("f__0"),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerEffectDefinitionTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenEffectDefinitionTests.java
index 051c03e4..4777f5a7 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerEffectDefinitionTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenEffectDefinitionTests.java
@@ -1,28 +1,28 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
-import org.shedlang.compiler.stackir.instructions.DefineEffectInstruction;
+import org.shedlang.compiler.shid.instructions.ShidDefineEffect;
 import org.shedlang.compiler.types.Effects;
 import org.shedlang.compiler.types.NamespaceName;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isLocalStoreInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isLocalStoreInstruction;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.*;
 
-public class StackCompilerEffectDefinitionTests {
+public class ShidCodeGenEffectDefinitionTests {
     @Test
     public void effectDefinitionIsCompiledToDefineEffectInstruction() {
         var effect = Effects.userDefined(NamespaceName.of("Example", "Project"), "State");
         var node = Typed.effectDefinition(effect);
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("State");
 
-        var result = StackCompiler.compileNamespaceStatement(node, context);
+        var result = ShidCodeGen.compileNamespaceStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             instanceOf(
-                DefineEffectInstruction.class,
+                ShidDefineEffect.class,
                 has("effect", x -> x.effect(), equalTo(effect))
             ),
             isLocalStoreInstruction("State__0")
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerExpressionStatementTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenExpressionStatementTests.java
index f644408b..05a47d39 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerExpressionStatementTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenExpressionStatementTests.java
@@ -1,20 +1,20 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isDiscardInstruction;
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isPushStringInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isDiscardInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isPushStringInstruction;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerExpressionStatementTests {
+public class ShidCodeGenExpressionStatementTests {
     @Test
     public void expressionIsEvaluatedAndTheResultDiscarded() {
         var node = Typed.expressionStatement(Typed.stringLiteral("hello"));
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileFunctionStatement(node, context);
+        var result = ShidCodeGen.compileFunctionStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushStringInstruction("hello"),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerFieldAccessTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenFieldAccessTests.java
index 4c0821a6..0e869445 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerFieldAccessTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenFieldAccessTests.java
@@ -1,18 +1,18 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
-import org.shedlang.compiler.stackir.instructions.FieldLoadInstruction;
+import org.shedlang.compiler.shid.instructions.ShidFieldLoad;
 import org.shedlang.compiler.types.Effects;
 import org.shedlang.compiler.types.NamespaceName;
 import org.shedlang.compiler.types.Types;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isFieldLoadInstruction;
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isLocalLoadInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isFieldLoadInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isLocalLoadInstruction;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerFieldAccessTests {
+public class ShidCodeGenFieldAccessTests {
     @Test
     public void namespaceFieldAccessIsCompiledToFieldLoad() {
         var namespaceType = Types.namespace(NamespaceName.of("Example", "Project"));
@@ -21,15 +21,15 @@ public class StackCompilerFieldAccessTests {
             "name",
             Types.STRING
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("Project");
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLocalLoadInstruction("Project__0"),
             isFieldLoadInstruction(
-                new FieldLoadInstruction.Receiver.Namespace(namespaceType.namespaceName()),
+                new ShidFieldLoad.Receiver.Namespace(namespaceType.namespaceName()),
                 "name"
             )
         ));
@@ -43,10 +43,10 @@ public class StackCompilerFieldAccessTests {
             "name",
             Types.STRING
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("user");
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLocalLoadInstruction("user__0"),
@@ -62,15 +62,15 @@ public class StackCompilerFieldAccessTests {
             "read",
             Types.STRING
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("State");
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLocalLoadInstruction("State__0"),
             isFieldLoadInstruction(
-                new FieldLoadInstruction.Receiver.Effect(effect),
+                new ShidFieldLoad.Receiver.Effect(effect),
                 "read"
             )
         ));
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerFunctionDefinitionTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenFunctionDefinitionTests.java
index d28a3eb5..0f6a3835 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerFunctionDefinitionTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenFunctionDefinitionTests.java
@@ -1,16 +1,16 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 import org.shedlang.compiler.ast.typed.TypedFunctionDefinitionNode;
-import org.shedlang.compiler.stackir.instructions.DefineFunctionInstruction;
+import org.shedlang.compiler.shid.instructions.ShidDefineFunction;
 import org.shedlang.compiler.types.Types;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.*;
 
-public class StackCompilerFunctionDefinitionTests {
+public class ShidCodeGenFunctionDefinitionTests {
     @Test
     public void functionIsCompiledToDefineFunctionInstruction() {
         var node = TypedFunctionDefinitionNode.builder()
@@ -20,15 +20,15 @@ public class StackCompilerFunctionDefinitionTests {
             .addFreeVariable("z")
             .addStatement(Typed.expressionStatement(Typed.stringLiteral("hello")))
             .build();
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("f")
             .addShedVal("z");
 
-        var result = StackCompiler.compileNamespaceStatement(node, context);
+        var result = ShidCodeGen.compileNamespaceStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             instanceOf(
-                DefineFunctionInstruction.class,
+                ShidDefineFunction.class,
                 has("name", x -> x.name(), equalTo("f")),
                 has("positionalParams", x -> x.positionalParams(), isSequence(
                     isDefineFunctionInstructionParam("x__0")
@@ -56,14 +56,14 @@ public class StackCompilerFunctionDefinitionTests {
             .withName("f")
             .addStatement(Typed.blockReturn(Typed.stringLiteral("hello")))
             .build();
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("f");
 
-        var result = StackCompiler.compileNamespaceStatement(node, context);
+        var result = ShidCodeGen.compileNamespaceStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             instanceOf(
-                DefineFunctionInstruction.class,
+                ShidDefineFunction.class,
                 has("body", x -> x.body(), isSequence(
                     isPushStringInstruction("hello"),
                     isReturnInstruction()
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerFunctionExpressionTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenFunctionExpressionTests.java
index d14356f7..c5f78340 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerFunctionExpressionTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenFunctionExpressionTests.java
@@ -1,16 +1,16 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 import org.shedlang.compiler.ast.typed.TypedFunctionExpressionNode;
-import org.shedlang.compiler.stackir.instructions.DefineFunctionInstruction;
+import org.shedlang.compiler.shid.instructions.ShidDefineFunction;
 import org.shedlang.compiler.types.Types;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.*;
 
-public class StackCompilerFunctionExpressionTests {
+public class ShidCodeGenFunctionExpressionTests {
     @Test
     public void functionIsCompiledToDefineFunctionInstruction() {
         var node = TypedFunctionExpressionNode.builder()
@@ -19,15 +19,15 @@ public class StackCompilerFunctionExpressionTests {
             .addFreeVariable("z")
             .addStatement(Typed.expressionStatement(Typed.stringLiteral("hello")))
             .build();
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("f")
             .addShedVal("z");
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             instanceOf(
-                DefineFunctionInstruction.class,
+                ShidDefineFunction.class,
                 has("name", x -> x.name(), equalTo("anonymous")),
                 has("positionalParams", x -> x.positionalParams(), isSequence(
                     isDefineFunctionInstructionParam("x__0")
@@ -53,14 +53,14 @@ public class StackCompilerFunctionExpressionTests {
         var node = TypedFunctionExpressionNode.builder()
             .addStatement(Typed.blockReturn(Typed.stringLiteral("hello")))
             .build();
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("f");
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             instanceOf(
-                DefineFunctionInstruction.class,
+                ShidDefineFunction.class,
                 has("body", x -> x.body(), isSequence(
                     isPushStringInstruction("hello"),
                     isReturnInstruction()
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerFunctionReturnTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenFunctionReturnTests.java
index 8bd5c64d..d6a63c1f 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerFunctionReturnTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenFunctionReturnTests.java
@@ -1,19 +1,19 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerFunctionReturnTests {
+public class ShidCodeGenFunctionReturnTests {
     @Test
     public void expressionIsEvaluatedAndReturned() {
         var node = Typed.functionReturn(Typed.stringLiteral("hello"));
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileFunctionStatement(node, context);
+        var result = ShidCodeGen.compileFunctionStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushStringInstruction("hello"),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerIfTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenIfTests.java
index dca0be02..f1f81e95 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerIfTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenIfTests.java
@@ -1,4 +1,4 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
@@ -6,11 +6,11 @@ import org.shedlang.compiler.types.Types;
 
 import java.util.List;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerIfTests {
+public class ShidCodeGenIfTests {
     @Test
     public void ifWithSingleConditionalBranchIsCompiledToSingleIfInstruction() {
         var node = Typed.if_(
@@ -27,10 +27,10 @@ public class StackCompilerIfTests {
             )),
             Types.INT
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("c");
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLocalLoadInstruction("c__0"),
@@ -68,11 +68,11 @@ public class StackCompilerIfTests {
             )),
             Types.INT
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("c")
             .addShedVal("d");
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLocalLoadInstruction("c__0"),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerIntAddTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenIntAddTests.java
index 4724b867..4ff0e6eb 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerIntAddTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenIntAddTests.java
@@ -1,23 +1,23 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isIntAddInstruction;
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isPushIntInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isIntAddInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isPushIntInstruction;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerIntAddTests {
+public class ShidCodeGenIntAddTests {
     @Test
     public void intAddIsCompiledToIntAddInstruction() {
         var node = Typed.intAdd(
             Typed.intLiteral(42),
             Typed.intLiteral(47)
         );
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushIntInstruction(42),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerIntEqualsTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenIntEqualsTests.java
index 61eb93f9..464e73f4 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerIntEqualsTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenIntEqualsTests.java
@@ -1,22 +1,22 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerIntEqualsTests {
+public class ShidCodeGenIntEqualsTests {
     @Test
     public void intEqualsIsCompiledToIntEqualsInstruction() {
         var node = Typed.intEquals(
             Typed.intLiteral(42),
             Typed.intLiteral(47)
         );
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushIntInstruction(42),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerIntLiteralTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenIntLiteralTests.java
index 402c6dac..ed95e765 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerIntLiteralTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenIntLiteralTests.java
@@ -1,19 +1,19 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isPushIntInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isPushIntInstruction;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerIntLiteralTests {
+public class ShidCodeGenIntLiteralTests {
     @Test
     public void intLiteralIsCompiledToPushIntInstruction() {
         var node = Typed.intLiteral(42);
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushIntInstruction(42)
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerIntNotEqualTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenIntNotEqualTests.java
index 8364bc81..9c55f222 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerIntNotEqualTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenIntNotEqualTests.java
@@ -1,22 +1,22 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerIntNotEqualTests {
+public class ShidCodeGenIntNotEqualTests {
     @Test
     public void intNotEqualsIsCompiledToIntNotEqualInstruction() {
         var node = Typed.intNotEqual(
             Typed.intLiteral(42),
             Typed.intLiteral(47)
         );
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushIntInstruction(42),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerIntSubTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenIntSubTests.java
index 110be63a..df3e9791 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerIntSubTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenIntSubTests.java
@@ -1,22 +1,22 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerIntSubTests {
+public class ShidCodeGenIntSubTests {
     @Test
     public void intSubIsCompiledToIntSubInstruction() {
         var node = Typed.intSub(
             Typed.intLiteral(42),
             Typed.intLiteral(47)
         );
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushIntInstruction(42),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerNamespaceTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenNamespaceTests.java
index 322bf49f..f56ba972 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerNamespaceTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenNamespaceTests.java
@@ -1,18 +1,18 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.*;
-import org.shedlang.compiler.stackir.instructions.*;
+import org.shedlang.compiler.shid.instructions.*;
 import org.shedlang.compiler.types.NamespaceName;
 import org.shedlang.compiler.types.Types;
 
 import java.util.List;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.*;
 
-public class StackCompilerNamespaceTests {
+public class ShidCodeGenNamespaceTests {
     @Test
     public void bodyOfNamespaceIsCompiledWithNamesBeingExported() {
         var namespaceName = new NamespaceName(List.of("Example"));
@@ -31,16 +31,16 @@ public class StackCompilerNamespaceTests {
             List.of("f")
         );
 
-        var stackIrNamespace = StackCompiler.compileNamespace(node);
+        var shidNamespace = ShidCodeGen.compileNamespace(node);
 
-        assertThat(stackIrNamespace.instructions(), isSequence(
+        assertThat(shidNamespace.instructions(), isSequence(
             // TODO: test the builtin loading properly
-            instanceOf(NamespaceImportInstruction.class),
-            instanceOf(FieldLoadInstruction.class),
-            instanceOf(LocalStoreInstruction.class),
+            instanceOf(ShidNamespaceImport.class),
+            instanceOf(ShidFieldLoad.class),
+            instanceOf(ShidLocalStore.class),
 
             instanceOf(
-                DefineFunctionInstruction.class,
+                ShidDefineFunction.class,
                 has("name", x -> x.name(), equalTo("f"))
             ),
             isLocalStoreInstruction("f__0"),
@@ -58,13 +58,13 @@ public class StackCompilerNamespaceTests {
             .addBoundVariable(BoundVariable.immutable("B"))
             .build();
 
-        var stackIrNamespace = StackCompiler.compileNamespace(node);
+        var shidNamespace = ShidCodeGen.compileNamespace(node);
 
-        assertThat(stackIrNamespace.instructions(), isSequence(
+        assertThat(shidNamespace.instructions(), isSequence(
             // TODO: test the builtin loading properly
-            instanceOf(NamespaceImportInstruction.class),
-            instanceOf(FieldLoadInstruction.class),
-            instanceOf(LocalStoreInstruction.class),
+            instanceOf(ShidNamespaceImport.class),
+            instanceOf(ShidFieldLoad.class),
+            instanceOf(ShidLocalStore.class),
 
             isNamespaceImportInstruction(NamespaceName.of("A")),
             isLocalStoreInstruction("A__0"),
@@ -91,21 +91,21 @@ public class StackCompilerNamespaceTests {
             List.of("f", "None")
         );
 
-        var stackIrNamespace = StackCompiler.compileNamespace(node);
+        var shidNamespace = ShidCodeGen.compileNamespace(node);
 
-        assertThat(stackIrNamespace.instructions(), isSequence(
+        assertThat(shidNamespace.instructions(), isSequence(
             // TODO: test the builtin loading properly
-            instanceOf(NamespaceImportInstruction.class),
-            instanceOf(FieldLoadInstruction.class),
-            instanceOf(LocalStoreInstruction.class),
+            instanceOf(ShidNamespaceImport.class),
+            instanceOf(ShidFieldLoad.class),
+            instanceOf(ShidLocalStore.class),
 
             instanceOf(
-                DefineStructInstruction.class,
+                ShidDefineStruct.class,
                 has("type", x -> x.type(), equalTo(structType))
             ),
             isLocalStoreInstruction("None__0"),
             instanceOf(
-                DefineFunctionInstruction.class,
+                ShidDefineFunction.class,
                 has("name", x -> x.name(), equalTo("f"))
             ),
             isLocalStoreInstruction("f__0"),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerReferenceTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenReferenceTests.java
index 038351c4..2a30266b 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerReferenceTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenReferenceTests.java
@@ -1,21 +1,21 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.BoundVariable;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerReferenceTests {
+public class ShidCodeGenReferenceTests {
     @Test
     public void referenceIsCompiledToLocalLoad() {
         var node = Typed.reference("x");
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVariable(BoundVariable.immutable("x"));
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLocalLoadInstruction("x__0")
@@ -25,14 +25,14 @@ public class StackCompilerReferenceTests {
     @Test
     public void whenLocalIsVarThenReferenceIsCompiledToVarLoad() {
         var node = Typed.reference("x");
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVariable(BoundVariable.mutable("x"));
-        context = StackCompiler.compileFunctionStatement(
+        context = ShidCodeGen.compileFunctionStatement(
             Typed.var("x", Typed.intLiteral(0)),
             context
         );
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushIntInstruction(0),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerResumeTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenResumeTests.java
index 8ee1f909..6992783d 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerResumeTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenResumeTests.java
@@ -1,19 +1,19 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerResumeTests {
+public class ShidCodeGenResumeTests {
     @Test
     public void expressionIsEvaluatedAndReturned() {
         var node = Typed.resume(Typed.stringLiteral("hello"));
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileFunctionStatement(node, context);
+        var result = ShidCodeGen.compileFunctionStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushStringInstruction("hello"),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerStringAddTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenStringAddTests.java
index 42557970..56b2750e 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerStringAddTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenStringAddTests.java
@@ -1,22 +1,22 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerStringAddTests {
+public class ShidCodeGenStringAddTests {
     @Test
     public void stringAddIsCompiledToStringAddInstruction() {
         var node = Typed.stringAdd(
             Typed.stringLiteral("a"),
             Typed.stringLiteral("b")
         );
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushStringInstruction("a"),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerStringLiteralTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenStringLiteralTests.java
index 44133713..b308c300 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerStringLiteralTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenStringLiteralTests.java
@@ -1,19 +1,19 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isPushStringInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isPushStringInstruction;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerStringLiteralTests {
+public class ShidCodeGenStringLiteralTests {
     @Test
     public void stringLiteralIsCompiledToPushStringInstruction() {
         var node = Typed.stringLiteral("hello");
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushStringInstruction("hello")
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerStructDefinitionTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenStructDefinitionTests.java
index 6dc845bd..4e989e9b 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerStructDefinitionTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenStructDefinitionTests.java
@@ -1,17 +1,17 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 import org.shedlang.compiler.ast.typed.TypedStructDefinitionNode;
-import org.shedlang.compiler.stackir.instructions.DefineStructInstruction;
+import org.shedlang.compiler.shid.instructions.ShidDefineStruct;
 import org.shedlang.compiler.types.NamespaceName;
 import org.shedlang.compiler.types.Types;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isLocalStoreInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isLocalStoreInstruction;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.*;
 
-public class StackCompilerStructDefinitionTests {
+public class ShidCodeGenStructDefinitionTests {
     @Test
     public void structDefinitionIsCompiledToDefineStructInstruction() {
         var structType = Types.struct(NamespaceName.of("Example", "Project"), "User");
@@ -20,14 +20,14 @@ public class StackCompilerStructDefinitionTests {
             .addField(Typed.structFieldDefinition("name", Typed.typeLevelReference("String", Types.STRING)))
             .addField(Typed.structFieldDefinition("isActive", Typed.typeLevelReference("Bool", Types.BOOL)))
             .build();
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("User");
 
-        var result = StackCompiler.compileNamespaceStatement(node, context);
+        var result = ShidCodeGen.compileNamespaceStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             instanceOf(
-                DefineStructInstruction.class,
+                ShidDefineStruct.class,
                 has("type", x -> x.type(), equalTo(structType)),
                 has("fields", x -> x.fields(), isSequence(
                     has("name", x -> x.name(), equalTo("name")),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerSumTypeDefinitionTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenSumTypeDefinitionTests.java
index 849e2df7..74521d29 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerSumTypeDefinitionTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenSumTypeDefinitionTests.java
@@ -1,26 +1,26 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 import org.shedlang.compiler.types.NamespaceName;
 import org.shedlang.compiler.types.Types;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isLocalStoreInstruction;
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isPushUnitInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isLocalStoreInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isPushUnitInstruction;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerSumTypeDefinitionTests {
+public class ShidCodeGenSumTypeDefinitionTests {
     @Test
     public void sumTypeDefinitionIsCompiledToUnit() {
         // TODO: this is a bit of a hack, we probably want to be able to have
         // sum types in some potential backends (e.g. the JVM)
         var sumType = Types.sum(NamespaceName.of("Example", "Project"), "Option");
         var node = Typed.sumTypeDefinition(sumType);
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("Option");
 
-        var result = StackCompiler.compileNamespaceStatement(node, context);
+        var result = ShidCodeGen.compileNamespaceStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushUnitInstruction(),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerTryTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenTryTests.java
index f4e87f8f..daff19b0 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerTryTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenTryTests.java
@@ -1,19 +1,19 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 import org.shedlang.compiler.ast.typed.TypedTryHandlerMethodNode;
 import org.shedlang.compiler.ast.typed.TypedTryNode;
-import org.shedlang.compiler.stackir.instructions.DefineFunctionInstruction;
-import org.shedlang.compiler.stackir.instructions.TryInstruction;
+import org.shedlang.compiler.shid.instructions.ShidDefineFunction;
+import org.shedlang.compiler.shid.instructions.ShidTry;
 import org.shedlang.compiler.types.Effects;
 import org.shedlang.compiler.types.NamespaceName;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isPushIntInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isPushIntInstruction;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.*;
 
-public class StackCompilerTryTests {
+public class ShidCodeGenTryTests {
     @Test
     public void tryNodeIsCompiledToTryInstruction() {
         var effect = Effects.userDefined(NamespaceName.of("Example"), "State");
@@ -33,22 +33,22 @@ public class StackCompilerTryTests {
                     .build()
             )
             .build();
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("c");
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             instanceOf(
-                DefineFunctionInstruction.class,
+                ShidDefineFunction.class,
                 has("name", x -> x.name(), equalTo("read"))
             ),
             instanceOf(
-                DefineFunctionInstruction.class,
+                ShidDefineFunction.class,
                 has("name", x -> x.name(), equalTo("write"))
             ),
             instanceOf(
-                TryInstruction.class,
+                ShidTry.class,
                 has("handledEffect", x -> x.handledEffect(), equalTo(effect)),
                 has("handlerMethodNames", x -> x.handlerMethodNames(), isSequence(
                     equalTo("read"),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerTupleTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenTupleTests.java
index f05e9257..c3194182 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerTupleTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenTupleTests.java
@@ -1,15 +1,15 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
 import java.util.List;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerTupleTests {
+public class ShidCodeGenTupleTests {
     @Test
     public void stringAddIsCompiledToStringAddInstruction() {
         var node = Typed.tuple(List.of(
@@ -17,9 +17,9 @@ public class StackCompilerTupleTests {
             Typed.boolLiteral(true),
             Typed.intLiteral(4)
         ));
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushStringInstruction("a"),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerUnitLiteralTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenUnitLiteralTests.java
index 024b9561..27b7ed6c 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerUnitLiteralTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenUnitLiteralTests.java
@@ -1,19 +1,19 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.isPushUnitInstruction;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.isPushUnitInstruction;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerUnitLiteralTests {
+public class ShidCodeGenUnitLiteralTests {
     @Test
     public void unitLiteralIsCompiledToPushUnitInstruction() {
         var node = Typed.unitLiteral();
-        var context = StackCompiler.Context.EMPTY;
+        var context = ShidCodeGen.Context.EMPTY;
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushUnitInstruction()
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerValTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenValTests.java
index 2e6194ca..5007e1e8 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerValTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenValTests.java
@@ -1,4 +1,4 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.BoundVariable;
@@ -7,18 +7,18 @@ import org.shedlang.compiler.types.Types;
 
 import java.util.List;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerValTests {
+public class ShidCodeGenValTests {
     @Test
     public void whenValIsFunctionStatementThenExpressionIsEvaluatedAndStoredAsLocal() {
         var node = Typed.val("x", Typed.stringLiteral("hello"));
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("x");
 
-        var result = StackCompiler.compileFunctionStatement(node, context);
+        var result = ShidCodeGen.compileFunctionStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushStringInstruction("hello"),
@@ -29,10 +29,10 @@ public class StackCompilerValTests {
     @Test
     public void whenValIsNamespaceStatementThenExpressionIsEvaluatedAndStoredAsLocal() {
         var node = Typed.val("x", Typed.stringLiteral("hello"));
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("x");
 
-        var result = StackCompiler.compileNamespaceStatement(node, context);
+        var result = ShidCodeGen.compileNamespaceStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushStringInstruction("hello"),
@@ -69,11 +69,11 @@ public class StackCompilerValTests {
             )),
             Typed.expressionStatement(Typed.reference("x"))
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("x");
 
         for (var node : nodes) {
-            context = StackCompiler.compileFunctionStatement(node, context);
+            context = ShidCodeGen.compileFunctionStatement(node, context);
         }
 
         assertThat(context.instructions(), isSequence(
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerVarTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenVarTests.java
index 7df00442..a1e264ad 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerVarTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenVarTests.java
@@ -1,20 +1,20 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerVarTests {
+public class ShidCodeGenVarTests {
     @Test
     public void expressionIsEvaluatedAndStoredAsVar() {
         var node = Typed.var("x", Typed.stringLiteral("hello"));
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("x");
 
-        var result = StackCompiler.compileFunctionStatement(node, context);
+        var result = ShidCodeGen.compileFunctionStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isPushStringInstruction("hello"),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerWhenTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenWhenTests.java
index d19eb525..f3e2880c 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerWhenTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenWhenTests.java
@@ -1,4 +1,4 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
@@ -7,11 +7,11 @@ import org.shedlang.compiler.types.Types;
 
 import java.util.List;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerWhenTests {
+public class ShidCodeGenWhenTests {
     private final static NamespaceName NAMESPACE_NAME = NamespaceName.of("Example", "Project");
 
     @Test
@@ -34,10 +34,10 @@ public class StackCompilerWhenTests {
             ),
             Types.STRING
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("x");
 
-        var result = StackCompiler.compileExpression(node, context);
+        var result = ShidCodeGen.compileExpression(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLocalLoadInstruction("x__0"),
diff --git a/src/test/java/org/shedlang/compiler/stackir/StackCompilerWhileTests.java b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenWhileTests.java
index 006c0b4c..1ab5240a 100644
--- a/src/test/java/org/shedlang/compiler/stackir/StackCompilerWhileTests.java
+++ b/src/test/java/org/shedlang/compiler/shid/ShidCodeGenWhileTests.java
@@ -1,15 +1,15 @@
-package org.shedlang.compiler.stackir;
+package org.shedlang.compiler.shid;
 
 import org.junit.jupiter.api.Test;
 import org.shedlang.compiler.ast.typed.Typed;
 
 import java.util.List;
 
-import static org.shedlang.compiler.stackir.instructions.InstructionMatchers.*;
+import static org.shedlang.compiler.shid.instructions.InstructionMatchers.*;
 import static org.zwobble.precisely.AssertThat.assertThat;
 import static org.zwobble.precisely.Matchers.isSequence;
 
-public class StackCompilerWhileTests {
+public class ShidCodeGenWhileTests {
     @Test
     public void whileIsCompiledToLoop() {
         var node = Typed.while_(
@@ -18,10 +18,10 @@ public class StackCompilerWhileTests {
                 Typed.expressionStatement(Typed.intLiteral(42))
             ))
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("c");
 
-        var result = StackCompiler.compileFunctionStatement(node, context);
+        var result = ShidCodeGen.compileFunctionStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLoopInstruction(
@@ -51,10 +51,10 @@ public class StackCompilerWhileTests {
                 Typed.blockReturn(Typed.intLiteral(42))
             ))
         );
-        var context = StackCompiler.Context.EMPTY
+        var context = ShidCodeGen.Context.EMPTY
             .addShedVal("c");
 
-        var result = StackCompiler.compileFunctionStatement(node, context);
+        var result = ShidCodeGen.compileFunctionStatement(node, context);
 
         assertThat(result.instructions(), isSequence(
             isLoopInstruction(
diff --git a/src/test/java/org/shedlang/compiler/shid/instructions/InstructionMatchers.java b/src/test/java/org/shedlang/compiler/shid/instructions/InstructionMatchers.java
new file mode 100644
index 00000000..c7c89825
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/shid/instructions/InstructionMatchers.java
@@ -0,0 +1,229 @@
+package org.shedlang.compiler.shid.instructions;
+
+import org.shedlang.compiler.types.NamespaceName;
+import org.shedlang.compiler.types.StructType;
+import org.zwobble.precisely.Matcher;
+
+import java.math.BigInteger;
+import java.util.List;
+
+import static org.zwobble.precisely.Matchers.*;
+
+public class InstructionMatchers {
+    private InstructionMatchers() {
+    }
+
+    public static Matcher<ShidInstruction> isCallInstruction(
+        int positionalArgCount,
+        List<String> namedArgNames
+    ) {
+        return instanceOf(
+            ShidCall.class,
+            has("positionalArgCount", x -> x.positionalArgCount(), equalTo(positionalArgCount)),
+            has("namedArgNames", x -> x.namedArgNames(), equalTo(namedArgNames))
+        );
+    }
+
+    public static Matcher<ShidDefineFunction.Param> isDefineFunctionInstructionParam(String name) {
+        return has("name", x -> x.name(), equalTo(name));
+    }
+
+    public static Matcher<ShidInstruction> isDiscardInstruction() {
+        return instanceOf(
+            ShidDiscard.class
+        );
+    }
+
+    public static Matcher<ShidInstruction> isDuplicateInstruction() {
+        return instanceOf(ShidDuplicate.class);
+    }
+
+    public static Matcher<ShidInstruction> isFieldLoadInstruction(
+        ShidFieldLoad.Receiver receiver,
+        String fieldName
+    ) {
+        return instanceOf(
+            ShidFieldLoad.class,
+            has("receiver", x -> x.receiver(), equalTo(receiver)),
+            has("fieldName", x -> x.fieldName(), equalTo(fieldName))
+        );
+    }
+
+    public static Matcher<ShidInstruction> isFieldLoadInstruction(
+        StructType receiverType,
+        String fieldName
+    ) {
+        return isFieldLoadInstruction(
+            new ShidFieldLoad.Receiver.Struct(receiverType),
+            fieldName
+        );
+    }
+
+    public static Matcher<ShidInstruction> isIfInstruction(
+        Matcher<Iterable<? extends ShidInstruction>> trueBody,
+        Matcher<Iterable<? extends ShidInstruction>> falseBody
+    ) {
+        return instanceOf(
+            ShidIf.class,
+            has("trueBody", x -> x.trueBody(), trueBody),
+            has("falseBody", x -> x.falseBody(), falseBody)
+        );
+    }
+
+    public static Matcher<ShidInstruction> isIntAddInstruction() {
+        return instanceOf(ShidIntAdd.class);
+    }
+
+    public static Matcher<ShidInstruction> isIntEqualsInstruction() {
+        return instanceOf(ShidIntEquals.class);
+    }
+
+    public static Matcher<ShidInstruction> isIntNotEqualInstruction() {
+        return instanceOf(ShidIntNotEqual.class);
+    }
+
+    public static Matcher<ShidInstruction> isIntSubInstruction() {
+        return instanceOf(ShidIntSub.class);
+    }
+
+    public static Matcher<ShidInstruction> isLocalLoadInstruction(String name) {
+        return instanceOf(
+            ShidLocalLoad.class,
+            has("name", x -> x.name(), equalTo(name))
+        );
+    }
+
+    public static Matcher<ShidInstruction> isLocalStoreInstruction(String name) {
+        return instanceOf(
+            ShidLocalStore.class,
+            has("name", x -> x.name(), equalTo(name))
+        );
+    }
+
+    public static Matcher<ShidInstruction> isLoopInstruction(
+        Matcher<Iterable<? extends ShidInstruction>> body
+    ) {
+        return instanceOf(
+            ShidLoop.class,
+            has("body", x -> x.body(), body)
+        );
+    }
+
+    public static Matcher<ShidInstruction> isLoopBreakInstruction() {
+        return instanceOf(ShidLoopBreak.class);
+    }
+
+    public static Matcher<ShidInstruction> isLoopContinueInstruction() {
+        return instanceOf(ShidLoopContinue.class);
+    }
+
+    public static Matcher<ShidInstruction> isNamespaceFieldStoreInstruction(
+        NamespaceName namespaceName,
+        String fieldName
+    ) {
+        return instanceOf(
+            ShidNamespaceFieldStore.class,
+            has("namespaceName", x -> x.namespaceName(), equalTo(namespaceName)),
+            has("fieldName", x -> x.fieldName(), equalTo(fieldName))
+        );
+    }
+
+    public static Matcher<ShidInstruction> isNamespaceImportInstruction(
+        NamespaceName namespaceName
+    ) {
+        return instanceOf(
+            ShidNamespaceImport.class,
+            has("namespaceName", x -> x.namespaceName(), equalTo(namespaceName))
+        );
+    }
+
+    public static Matcher<ShidInstruction> isPushBoolInstruction(boolean value) {
+        return instanceOf(
+            ShidPushBool.class,
+            has("value", x -> x.value(), equalTo(value))
+        );
+    }
+
+    public static Matcher<ShidInstruction> isPushIntInstruction(int value) {
+        return instanceOf(
+            ShidPushInt.class,
+            has("value", x -> x.value(), equalTo(BigInteger.valueOf(value)))
+        );
+    }
+
+    public static Matcher<ShidInstruction> isPushStringInstruction(String value) {
+        return instanceOf(
+            ShidPushString.class,
+            has("value", x -> x.value(), equalTo(value))
+        );
+    }
+
+    public static Matcher<ShidInstruction> isPushUnitInstruction() {
+        return instanceOf(
+            ShidPushUnit.class
+        );
+    }
+
+    public static Matcher<ShidInstruction> isResumeInstruction() {
+        return instanceOf(
+            ShidResume.class
+        );
+    }
+
+    public static Matcher<ShidInstruction> isReturnInstruction() {
+        return instanceOf(
+            ShidReturn.class
+        );
+    }
+
+    public static Matcher<ShidInstruction> isStringAddInstruction() {
+        return instanceOf(ShidStringAdd.class);
+    }
+
+    public static Matcher<ShidInstruction> isSwitchInstruction(
+        Matcher<Iterable<? extends ShidSwitch.Case>> cases
+    ) {
+        return instanceOf(
+            ShidSwitch.class,
+            has("cases", x -> x.cases(), cases)
+        );
+    }
+
+    public static Matcher<ShidSwitch.Case> isSwitchInstructionCase(
+        StructType caseType,
+        Matcher<Iterable<? extends ShidInstruction>> body
+    ) {
+        return allOf(
+            has("caseType", x -> x.caseType(), equalTo(caseType)),
+            has("body", x -> x.body(), body)
+        );
+    }
+
+    public static Matcher<ShidInstruction> isTupleCreateInstruction(int elementCount) {
+        return instanceOf(
+            ShidTupleCreate.class,
+            has("elementCount", x -> x.elementCount(), equalTo(elementCount))
+        );
+    }
+
+    public static Matcher<ShidInstruction> isTupleGetInstruction(int elementIndex) {
+        return instanceOf(
+            ShidTupleGet.class,
+            has("elementIndex", x -> x.elementIndex(), equalTo(elementIndex))
+        );
+    }
+
+    public static Matcher<ShidInstruction> isVarLoadInstruction(String name) {
+        return instanceOf(
+            ShidVarLoad.class,
+            has("name", x -> x.name(), equalTo(name))
+        );
+    }
+
+    public static Matcher<ShidInstruction> isVarStoreInstruction(String name) {
+        return instanceOf(
+            ShidVarStore.class,
+            has("name", x -> x.name(), equalTo(name))
+        );
+    }
+}
diff --git a/src/test/java/org/shedlang/compiler/shid/instructions/Shid.java b/src/test/java/org/shedlang/compiler/shid/instructions/Shid.java
new file mode 100644
index 00000000..cd8e41fd
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/shid/instructions/Shid.java
@@ -0,0 +1,193 @@
+package org.shedlang.compiler.shid.instructions;
+
+import org.shedlang.compiler.sources.Sources;
+import org.shedlang.compiler.types.NamespaceName;
+import org.shedlang.compiler.types.StructType;
+import org.shedlang.compiler.types.UserDefinedEffect;
+
+import java.math.BigInteger;
+import java.util.List;
+
+public class Shid {
+    private Shid() {
+    }
+
+    public static ShidInstruction call(int positionalArgCount, List<String> namedArgNames) {
+        return new ShidCall(positionalArgCount, namedArgNames, Sources.NULL);
+    }
+
+    public static ShidInstruction defineEffect(UserDefinedEffect effect) {
+        return new ShidDefineEffect(effect, Sources.NULL);
+    }
+
+    public static ShidInstruction defineStruct(
+        StructType type,
+        List<ShidDefineStruct.Field> fields
+    ) {
+        return new ShidDefineStruct(
+            type,
+            fields,
+            Sources.NULL
+        );
+    }
+
+    public static ShidDefineStruct.Field defineStructField(String name) {
+        return new ShidDefineStruct.Field(name, Sources.NULL);
+    }
+
+    public static ShidInstruction discard() {
+        return new ShidDiscard(Sources.NULL);
+    }
+
+    public static ShidInstruction duplicate() {
+        return new ShidDuplicate(Sources.NULL);
+    }
+
+    public static ShidInstruction fieldLoad(NamespaceName namespaceName, String fieldName) {
+        return new ShidFieldLoad(
+            new ShidFieldLoad.Receiver.Namespace(namespaceName),
+            fieldName,
+            Sources.NULL
+        );
+    }
+
+    public static ShidInstruction fieldLoad(StructType type, String fieldName) {
+        return new ShidFieldLoad(
+            new ShidFieldLoad.Receiver.Struct(type),
+            fieldName,
+            Sources.NULL
+        );
+    }
+
+    public static ShidInstruction fieldLoad(UserDefinedEffect effect, String fieldName) {
+        return new ShidFieldLoad(
+            new ShidFieldLoad.Receiver.Effect(effect),
+            fieldName,
+            Sources.NULL
+        );
+    }
+
+    public static ShidInstruction if_(
+        int resultCount,
+        List<ShidInstruction> trueBody,
+        List<ShidInstruction> falseBody
+    ) {
+        return new ShidIf(resultCount, trueBody, falseBody, Sources.NULL);
+    }
+
+    public static ShidInstruction intAdd() {
+        return new ShidIntAdd(Sources.NULL);
+    }
+
+    public static ShidInstruction intEquals() {
+        return new ShidIntEquals(Sources.NULL);
+    }
+
+    public static ShidInstruction intNotEqual() {
+        return new ShidIntNotEqual(Sources.NULL);
+    }
+
+    public static ShidInstruction intSub() {
+        return new ShidIntSub(Sources.NULL);
+    }
+
+    public static ShidInstruction localLoad(String name) {
+        return new ShidLocalLoad(name, Sources.NULL);
+    }
+
+    public static ShidInstruction localStore(String name) {
+        return new ShidLocalStore(name, Sources.NULL);
+    }
+
+    public static ShidInstruction loop(List<ShidInstruction> body) {
+        return new ShidLoop(body, Sources.NULL);
+    }
+
+    public static ShidInstruction loopBreak() {
+        return new ShidLoopBreak(Sources.NULL);
+    }
+
+    public static ShidInstruction loopContinue() {
+        return new ShidLoopContinue(Sources.NULL);
+    }
+
+    public static ShidInstruction namespaceFieldStore(NamespaceName namespaceName, String fieldName) {
+        return new ShidNamespaceFieldStore(namespaceName, fieldName, Sources.NULL);
+    }
+
+    public static ShidInstruction namespaceImport(NamespaceName namespaceName) {
+        return new ShidNamespaceImport(namespaceName, Sources.NULL);
+    }
+
+    public static ShidDefineFunction.Param param(String name) {
+        return new ShidDefineFunction.Param(name, Sources.NULL);
+    }
+
+    public static ShidInstruction pushBool(boolean value) {
+        return new ShidPushBool(value, Sources.NULL);
+    }
+
+    public static ShidInstruction pushInt(int value) {
+        return new ShidPushInt(BigInteger.valueOf(value), Sources.NULL);
+    }
+
+    public static ShidInstruction pushString(String value) {
+        return new ShidPushString(value, Sources.NULL);
+    }
+
+    public static ShidInstruction pushUnit() {
+        return new ShidPushUnit(Sources.NULL);
+    }
+
+    public static ShidInstruction resume() {
+        return new ShidResume(Sources.NULL);
+    }
+
+    public static ShidInstruction return_() {
+        return new ShidReturn(Sources.NULL);
+    }
+
+    public static ShidInstruction stringAdd() {
+        return new ShidStringAdd(Sources.NULL);
+    }
+
+    public static ShidInstruction switch_(List<ShidSwitch.Case> cases) {
+        return new ShidSwitch(cases, Sources.NULL);
+    }
+
+    public static ShidSwitch.Case switchCase(
+        StructType type,
+        List<ShidInstruction> body
+    ) {
+        return new ShidSwitch.Case(type, body, Sources.NULL);
+    }
+
+    public static ShidInstruction try_(
+        UserDefinedEffect handledEffect,
+        List<String> handlerMethodNames,
+        List<ShidInstruction> body
+    ) {
+        return new ShidTry(
+            handledEffect,
+            handlerMethodNames,
+            body,
+            Sources.NULL
+        );
+    }
+
+    public static ShidInstruction tupleCreate(int elementCount) {
+        return new ShidTupleCreate(elementCount, Sources.NULL);
+    }
+
+    public static ShidInstruction tupleGet(int elementIndex, int elementCount) {
+        return new ShidTupleGet(elementIndex, elementCount, Sources.NULL);
+    }
+
+    public static ShidInstruction varLoad(String name) {
+        return new ShidVarLoad(name, Sources.NULL);
+    }
+
+    public static ShidInstruction varStore(String name) {
+        return new ShidVarStore(name, Sources.NULL);
+    }
+}
diff --git a/src/test/java/org/shedlang/compiler/stackir/instructions/InstructionMatchers.java b/src/test/java/org/shedlang/compiler/stackir/instructions/InstructionMatchers.java
deleted file mode 100644
index 34c94f0e..00000000
--- a/src/test/java/org/shedlang/compiler/stackir/instructions/InstructionMatchers.java
+++ /dev/null
@@ -1,229 +0,0 @@
-package org.shedlang.compiler.stackir.instructions;
-
-import org.shedlang.compiler.types.NamespaceName;
-import org.shedlang.compiler.types.StructType;
-import org.zwobble.precisely.Matcher;
-
-import java.math.BigInteger;
-import java.util.List;
-
-import static org.zwobble.precisely.Matchers.*;
-
-public class InstructionMatchers {
-    private InstructionMatchers() {
-    }
-
-    public static Matcher<Instruction> isCallInstruction(
-        int positionalArgCount,
-        List<String> namedArgNames
-    ) {
-        return instanceOf(
-            CallInstruction.class,
-            has("positionalArgCount", x -> x.positionalArgCount(), equalTo(positionalArgCount)),
-            has("namedArgNames", x -> x.namedArgNames(), equalTo(namedArgNames))
-        );
-    }
-
-    public static Matcher<DefineFunctionInstruction.Param> isDefineFunctionInstructionParam(String name) {
-        return has("name", x -> x.name(), equalTo(name));
-    }
-
-    public static Matcher<Instruction> isDiscardInstruction() {
-        return instanceOf(
-            DiscardInstruction.class
-        );
-    }
-
-    public static Matcher<Instruction> isDuplicateInstruction() {
-        return instanceOf(DuplicateInstruction.class);
-    }
-
-    public static Matcher<Instruction> isFieldLoadInstruction(
-        FieldLoadInstruction.Receiver receiver,
-        String fieldName
-    ) {
-        return instanceOf(
-            FieldLoadInstruction.class,
-            has("receiver", x -> x.receiver(), equalTo(receiver)),
-            has("fieldName", x -> x.fieldName(), equalTo(fieldName))
-        );
-    }
-
-    public static Matcher<Instruction> isFieldLoadInstruction(
-        StructType receiverType,
-        String fieldName
-    ) {
-        return isFieldLoadInstruction(
-            new FieldLoadInstruction.Receiver.Struct(receiverType),
-            fieldName
-        );
-    }
-
-    public static Matcher<Instruction> isIfInstruction(
-        Matcher<Iterable<? extends Instruction>> trueBody,
-        Matcher<Iterable<? extends Instruction>> falseBody
-    ) {
-        return instanceOf(
-            IfInstruction.class,
-            has("trueBody", x -> x.trueBody(), trueBody),
-            has("falseBody", x -> x.falseBody(), falseBody)
-        );
-    }
-
-    public static Matcher<Instruction> isIntAddInstruction() {
-        return instanceOf(IntAddInstruction.class);
-    }
-
-    public static Matcher<Instruction> isIntEqualsInstruction() {
-        return instanceOf(IntEqualsInstruction.class);
-    }
-
-    public static Matcher<Instruction> isIntNotEqualInstruction() {
-        return instanceOf(IntNotEqualInstruction.class);
-    }
-
-    public static Matcher<Instruction> isIntSubInstruction() {
-        return instanceOf(IntSubInstruction.class);
-    }
-
-    public static Matcher<Instruction> isLocalLoadInstruction(String name) {
-        return instanceOf(
-            LocalLoadInstruction.class,
-            has("name", x -> x.name(), equalTo(name))
-        );
-    }
-
-    public static Matcher<Instruction> isLocalStoreInstruction(String name) {
-        return instanceOf(
-            LocalStoreInstruction.class,
-            has("name", x -> x.name(), equalTo(name))
-        );
-    }
-
-    public static Matcher<Instruction> isLoopInstruction(
-        Matcher<Iterable<? extends Instruction>> body
-    ) {
-        return instanceOf(
-            LoopInstruction.class,
-            has("body", x -> x.body(), body)
-        );
-    }
-
-    public static Matcher<Instruction> isLoopBreakInstruction() {
-        return instanceOf(LoopBreakInstruction.class);
-    }
-
-    public static Matcher<Instruction> isLoopContinueInstruction() {
-        return instanceOf(LoopContinueInstruction.class);
-    }
-
-    public static Matcher<Instruction> isNamespaceFieldStoreInstruction(
-        NamespaceName namespaceName,
-        String fieldName
-    ) {
-        return instanceOf(
-            NamespaceFieldStoreInstruction.class,
-            has("namespaceName", x -> x.namespaceName(), equalTo(namespaceName)),
-            has("fieldName", x -> x.fieldName(), equalTo(fieldName))
-        );
-    }
-
-    public static Matcher<Instruction> isNamespaceImportInstruction(
-        NamespaceName namespaceName
-    ) {
-        return instanceOf(
-            NamespaceImportInstruction.class,
-            has("namespaceName", x -> x.namespaceName(), equalTo(namespaceName))
-        );
-    }
-
-    public static Matcher<Instruction> isPushBoolInstruction(boolean value) {
-        return instanceOf(
-            PushBoolInstruction.class,
-            has("value", x -> x.value(), equalTo(value))
-        );
-    }
-
-    public static Matcher<Instruction> isPushIntInstruction(int value) {
-        return instanceOf(
-            PushIntInstruction.class,
-            has("value", x -> x.value(), equalTo(BigInteger.valueOf(value)))
-        );
-    }
-
-    public static Matcher<Instruction> isPushStringInstruction(String value) {
-        return instanceOf(
-            PushStringInstruction.class,
-            has("value", x -> x.value(), equalTo(value))
-        );
-    }
-
-    public static Matcher<Instruction> isPushUnitInstruction() {
-        return instanceOf(
-            PushUnitInstruction.class
-        );
-    }
-
-    public static Matcher<Instruction> isResumeInstruction() {
-        return instanceOf(
-            ResumeInstruction.class
-        );
-    }
-
-    public static Matcher<Instruction> isReturnInstruction() {
-        return instanceOf(
-            ReturnInstruction.class
-        );
-    }
-
-    public static Matcher<Instruction> isStringAddInstruction() {
-        return instanceOf(StringAddInstruction.class);
-    }
-
-    public static Matcher<Instruction> isSwitchInstruction(
-        Matcher<Iterable<? extends SwitchInstruction.Case>> cases
-    ) {
-        return instanceOf(
-            SwitchInstruction.class,
-            has("cases", x -> x.cases(), cases)
-        );
-    }
-
-    public static Matcher<SwitchInstruction.Case> isSwitchInstructionCase(
-        StructType caseType,
-        Matcher<Iterable<? extends Instruction>> body
-    ) {
-        return allOf(
-            has("caseType", x -> x.caseType(), equalTo(caseType)),
-            has("body", x -> x.body(), body)
-        );
-    }
-
-    public static Matcher<Instruction> isTupleCreateInstruction(int elementCount) {
-        return instanceOf(
-            TupleCreateInstruction.class,
-            has("elementCount", x -> x.elementCount(), equalTo(elementCount))
-        );
-    }
-
-    public static Matcher<Instruction> isTupleGetInstruction(int elementIndex) {
-        return instanceOf(
-            TupleGetInstruction.class,
-            has("elementIndex", x -> x.elementIndex(), equalTo(elementIndex))
-        );
-    }
-
-    public static Matcher<Instruction> isVarLoadInstruction(String name) {
-        return instanceOf(
-            VarLoadInstruction.class,
-            has("name", x -> x.name(), equalTo(name))
-        );
-    }
-
-    public static Matcher<Instruction> isVarStoreInstruction(String name) {
-        return instanceOf(
-            VarStoreInstruction.class,
-            has("name", x -> x.name(), equalTo(name))
-        );
-    }
-}
diff --git a/src/test/java/org/shedlang/compiler/stackir/instructions/Instructions.java b/src/test/java/org/shedlang/compiler/stackir/instructions/Instructions.java
deleted file mode 100644
index ce6ebf37..00000000
--- a/src/test/java/org/shedlang/compiler/stackir/instructions/Instructions.java
+++ /dev/null
@@ -1,193 +0,0 @@
-package org.shedlang.compiler.stackir.instructions;
-
-import org.shedlang.compiler.sources.Sources;
-import org.shedlang.compiler.types.NamespaceName;
-import org.shedlang.compiler.types.StructType;
-import org.shedlang.compiler.types.UserDefinedEffect;
-
-import java.math.BigInteger;
-import java.util.List;
-
-public class Instructions {
-    private Instructions() {
-    }
-
-    public static Instruction call(int positionalArgCount, List<String> namedArgNames) {
-        return new CallInstruction(positionalArgCount, namedArgNames, Sources.NULL);
-    }
-
-    public static Instruction defineEffect(UserDefinedEffect effect) {
-        return new DefineEffectInstruction(effect, Sources.NULL);
-    }
-
-    public static Instruction defineStruct(
-        StructType type,
-        List<DefineStructInstruction.Field> fields
-    ) {
-        return new DefineStructInstruction(
-            type,
-            fields,
-            Sources.NULL
-        );
-    }
-
-    public static DefineStructInstruction.Field defineStructField(String name) {
-        return new DefineStructInstruction.Field(name, Sources.NULL);
-    }
-
-    public static Instruction discard() {
-        return new DiscardInstruction(Sources.NULL);
-    }
-
-    public static Instruction duplicate() {
-        return new DuplicateInstruction(Sources.NULL);
-    }
-
-    public static Instruction fieldLoad(NamespaceName namespaceName, String fieldName) {
-        return new FieldLoadInstruction(
-            new FieldLoadInstruction.Receiver.Namespace(namespaceName),
-            fieldName,
-            Sources.NULL
-        );
-    }
-
-    public static Instruction fieldLoad(StructType type, String fieldName) {
-        return new FieldLoadInstruction(
-            new FieldLoadInstruction.Receiver.Struct(type),
-            fieldName,
-            Sources.NULL
-        );
-    }
-
-    public static Instruction fieldLoad(UserDefinedEffect effect, String fieldName) {
-        return new FieldLoadInstruction(
-            new FieldLoadInstruction.Receiver.Effect(effect),
-            fieldName,
-            Sources.NULL
-        );
-    }
-
-    public static Instruction if_(
-        int resultCount,
-        List<Instruction> trueBody,
-        List<Instruction> falseBody
-    ) {
-        return new IfInstruction(resultCount, trueBody, falseBody, Sources.NULL);
-    }
-
-    public static Instruction intAdd() {
-        return new IntAddInstruction(Sources.NULL);
-    }
-
-    public static Instruction intEquals() {
-        return new IntEqualsInstruction(Sources.NULL);
-    }
-
-    public static Instruction intNotEqual() {
-        return new IntNotEqualInstruction(Sources.NULL);
-    }
-
-    public static Instruction intSub() {
-        return new IntSubInstruction(Sources.NULL);
-    }
-
-    public static Instruction localLoad(String name) {
-        return new LocalLoadInstruction(name, Sources.NULL);
-    }
-
-    public static Instruction localStore(String name) {
-        return new LocalStoreInstruction(name, Sources.NULL);
-    }
-
-    public static Instruction loop(List<Instruction> body) {
-        return new LoopInstruction(body, Sources.NULL);
-    }
-
-    public static Instruction loopBreak() {
-        return new LoopBreakInstruction(Sources.NULL);
-    }
-
-    public static Instruction loopContinue() {
-        return new LoopContinueInstruction(Sources.NULL);
-    }
-
-    public static Instruction namespaceFieldStore(NamespaceName namespaceName, String fieldName) {
-        return new NamespaceFieldStoreInstruction(namespaceName, fieldName, Sources.NULL);
-    }
-
-    public static Instruction namespaceImport(NamespaceName namespaceName) {
-        return new NamespaceImportInstruction(namespaceName, Sources.NULL);
-    }
-
-    public static DefineFunctionInstruction.Param param(String name) {
-        return new DefineFunctionInstruction.Param(name, Sources.NULL);
-    }
-
-    public static Instruction pushBool(boolean value) {
-        return new PushBoolInstruction(value, Sources.NULL);
-    }
-
-    public static Instruction pushInt(int value) {
-        return new PushIntInstruction(BigInteger.valueOf(value), Sources.NULL);
-    }
-
-    public static Instruction pushString(String value) {
-        return new PushStringInstruction(value, Sources.NULL);
-    }
-
-    public static Instruction pushUnit() {
-        return new PushUnitInstruction(Sources.NULL);
-    }
-
-    public static Instruction resume() {
-        return new ResumeInstruction(Sources.NULL);
-    }
-
-    public static Instruction return_() {
-        return new ReturnInstruction(Sources.NULL);
-    }
-
-    public static Instruction stringAdd() {
-        return new StringAddInstruction(Sources.NULL);
-    }
-
-    public static Instruction switch_(List<SwitchInstruction.Case> cases) {
-        return new SwitchInstruction(cases, Sources.NULL);
-    }
-
-    public static SwitchInstruction.Case switchCase(
-        StructType type,
-        List<Instruction> body
-    ) {
-        return new SwitchInstruction.Case(type, body, Sources.NULL);
-    }
-
-    public static Instruction try_(
-        UserDefinedEffect handledEffect,
-        List<String> handlerMethodNames,
-        List<Instruction> body
-    ) {
-        return new TryInstruction(
-            handledEffect,
-            handlerMethodNames,
-            body,
-            Sources.NULL
-        );
-    }
-
-    public static Instruction tupleCreate(int elementCount) {
-        return new TupleCreateInstruction(elementCount, Sources.NULL);
-    }
-
-    public static Instruction tupleGet(int elementIndex, int elementCount) {
-        return new TupleGetInstruction(elementIndex, elementCount, Sources.NULL);
-    }
-
-    public static Instruction varLoad(String name) {
-        return new VarLoadInstruction(name, Sources.NULL);
-    }
-
-    public static Instruction varStore(String name) {
-        return new VarStoreInstruction(name, Sources.NULL);
-    }
-}