diff --git a/compiler/forget/src/HIR/Environment.ts b/compiler/forget/src/HIR/Environment.ts
index b8806ee80d..487900d013 100644
--- a/compiler/forget/src/HIR/Environment.ts
+++ b/compiler/forget/src/HIR/Environment.ts
@@ -1,7 +1,17 @@
+import invariant from "invariant";
 import { log } from "../Utils/logger";
 import { DEFAULT_GLOBALS, Global } from "./Globals";
-import { Effect, IdentifierId, makeIdentifierId, ValueKind } from "./HIR";
+import {
+  BuiltInType,
+  Effect,
+  FunctionType,
+  IdentifierId,
+  makeIdentifierId,
+  Type,
+  ValueKind,
+} from "./HIR";
 import { BUILTIN_HOOKS, Hook } from "./Hooks";
+import { BUILTIN_SHAPES, FunctionSignature } from "./ObjectShape";
 
 const HOOK_PATTERN = /^_?use/;
 
@@ -64,4 +74,32 @@ export class Environment {
       valueKind: ValueKind.Mutable,
     };
   }
+
+  getPropertyType(receiver: Type, property: string): BuiltInType | null {
+    if (receiver.kind === "Object" || receiver.kind === "Function") {
+      const { shapeId } = receiver;
+      if (shapeId !== null) {
+        const shape = BUILTIN_SHAPES.get(shapeId);
+        invariant(
+          shape !== undefined,
+          `[HIR] Forget internal error: cannot resolve shape ${shapeId}`
+        );
+        return shape.properties.get(property) ?? null;
+      }
+    }
+    return null;
+  }
+
+  getFunctionSignature(type: FunctionType): FunctionSignature | null {
+    const { shapeId } = type;
+    if (shapeId !== null) {
+      const shape = BUILTIN_SHAPES.get(shapeId);
+      invariant(
+        shape !== undefined,
+        `[HIR] Forget internal error: cannot resolve shape ${shapeId}`
+      );
+      return shape.functionType;
+    }
+    return null;
+  }
 }
diff --git a/compiler/forget/src/HIR/HIR.ts b/compiler/forget/src/HIR/HIR.ts
index 6e4bb101aa..9a1e1e374d 100644
--- a/compiler/forget/src/HIR/HIR.ts
+++ b/compiler/forget/src/HIR/HIR.ts
@@ -445,6 +445,9 @@ export type Phi = {
  *      may be different for ComputedCalls
  *  - {@link PropertyCall.property} remains an rval (i.e. never promoted to a
  *    named identifier). We currently rely on this for codegen.
+ *
+ * Type inference does not currently guarantee that {@link PropertyCall.property}
+ * is a FunctionType.
  */
 type PropertyCall = {
   kind: "PropertyCall";
diff --git a/compiler/forget/src/HIR/PrintHIR.ts b/compiler/forget/src/HIR/PrintHIR.ts
index 65821ed1ab..9139f7e885 100644
--- a/compiler/forget/src/HIR/PrintHIR.ts
+++ b/compiler/forget/src/HIR/PrintHIR.ts
@@ -269,9 +269,9 @@ export function printInstructionValue(instrValue: ReactiveValue): string {
       break;
     }
     case "PropertyCall": {
-      value = `PropertyCall ${printPlace(instrValue.receiver)}.${
+      value = `PropertyCall ${printPlace(instrValue.receiver)}.${printPlace(
         instrValue.property
-      }(${instrValue.args.map((arg) => printPattern(arg)).join(", ")})`;
+      )}(${instrValue.args.map((arg) => printPattern(arg)).join(", ")})`;
       break;
     }
     case "ComputedCall": {
diff --git a/compiler/forget/src/TypeInference/InferTypes.ts b/compiler/forget/src/TypeInference/InferTypes.ts
index 72b977a4e9..6c3563fa0f 100644
--- a/compiler/forget/src/TypeInference/InferTypes.ts
+++ b/compiler/forget/src/TypeInference/InferTypes.ts
@@ -4,6 +4,7 @@ import { Environment } from "../HIR";
 import {
   HIRFunction,
   Instruction,
+  makeType,
   Type,
   typeEquals,
   TypeId,
@@ -37,7 +38,7 @@ function isPrimitiveBinaryOp(op: t.BinaryExpression["operator"]): boolean {
 }
 
 export default function (func: HIRFunction): void {
-  const unifier = new Unifier();
+  const unifier = new Unifier(func.env);
   for (const e of generate(func)) {
     unifier.unify(e.left, e.right);
   }
@@ -62,12 +63,25 @@ function apply(func: HIRFunction, unifier: Unifier): void {
   }
 }
 
-type TypeEquation = {
-  left: Type;
-  right: Type;
+type FunctionCallType = {
+  kind: "FunctionCall";
+  returnType: TypeVar;
 };
 
-function equation(left: Type, right: Type): TypeEquation {
+type PolyType =
+  | {
+      kind: "Property";
+      object: Type;
+      propertyName: string;
+    }
+  | FunctionCallType;
+
+type TypeEquation = {
+  left: Type;
+  right: Type | PolyType;
+};
+
+function equation(left: Type, right: Type | PolyType): TypeEquation {
   return {
     left,
     right,
@@ -169,14 +183,67 @@ function* generateInstructionTypes(
       }
       break;
     }
+
+    case "PropertyLoad": {
+      if (left) {
+        yield equation(left, {
+          kind: "Property",
+          object: value.object.identifier.type,
+          propertyName: value.property,
+        });
+      }
+      break;
+    }
+
+    case "PropertyCall": {
+      const returnType = makeType();
+      yield equation(value.property.identifier.type, {
+        kind: "FunctionCall",
+        returnType,
+      });
+      if (left) {
+        yield equation(left, returnType);
+      }
+    }
   }
 }
 
 type Substitution = Map<TypeId, Type>;
 class Unifier {
   substitutions: Substitution = new Map();
+  env: Environment;
+
+  constructor(env: Environment) {
+    this.env = env;
+  }
+
+  unifyFunctionCall(tA: Type, tB: FunctionCallType): void {
+    const propertyType = this.get(tA);
+    if (propertyType.kind === "Function") {
+      const fn = this.env.getFunctionSignature(propertyType);
+      const returnType = fn?.returnType ?? null;
+      if (returnType !== null) {
+        this.unify(tB.returnType, returnType);
+      }
+    }
+  }
+
+  unify(tA: Type, tB: Type | PolyType): void {
+    if (tB.kind === "Property") {
+      const objectType = this.get(tB.object);
+      const propertyType = this.env.getPropertyType(
+        objectType,
+        tB.propertyName
+      );
+      if (propertyType !== null) {
+        this.unify(tA, propertyType);
+      }
+      return;
+    } else if (tB.kind === "FunctionCall") {
+      this.unifyFunctionCall(tA, tB);
+      return;
+    }
 
-  unify(tA: Type, tB: Type): void {
     if (typeEquals(tA, tB)) {
       return;
     }
diff --git a/compiler/forget/src/__tests__/fixtures/compiler/array-properties.expect.md b/compiler/forget/src/__tests__/fixtures/compiler/array-properties.expect.md
new file mode 100644
index 0000000000..2c4bc324b0
--- /dev/null
+++ b/compiler/forget/src/__tests__/fixtures/compiler/array-properties.expect.md
@@ -0,0 +1,50 @@
+
+## Input
+
+```javascript
+function Component(props) {
+  const a = [props.a, props.b, "hello"];
+  const x = a.length;
+  const y = a.push;
+  return { a, x, y, z: a.concat };
+}
+
+```
+
+## Code
+
+```javascript
+function Component(props) {
+  const $ = React.unstable_useMemoCache(7);
+  const c_0 = $[0] !== props.a;
+  const c_1 = $[1] !== props.b;
+  let t0;
+  if (c_0 || c_1) {
+    t0 = [props.a, props.b, "hello"];
+    $[0] = props.a;
+    $[1] = props.b;
+    $[2] = t0;
+  } else {
+    t0 = $[2];
+  }
+  const a = t0;
+  const x = a.length;
+  const y = a.push;
+  const c_3 = $[3] !== a;
+  const c_4 = $[4] !== x;
+  const c_5 = $[5] !== y;
+  let t1;
+  if (c_3 || c_4 || c_5) {
+    t1 = { a, x, y, z: a.concat };
+    $[3] = a;
+    $[4] = x;
+    $[5] = y;
+    $[6] = t1;
+  } else {
+    t1 = $[6];
+  }
+  return t1;
+}
+
+```
+      
\ No newline at end of file
diff --git a/compiler/forget/src/__tests__/fixtures/compiler/array-properties.js b/compiler/forget/src/__tests__/fixtures/compiler/array-properties.js
new file mode 100644
index 0000000000..8d314feb33
--- /dev/null
+++ b/compiler/forget/src/__tests__/fixtures/compiler/array-properties.js
@@ -0,0 +1,6 @@
+function Component(props) {
+  const a = [props.a, props.b, "hello"];
+  const x = a.length;
+  const y = a.push;
+  return { a, x, y, z: a.concat };
+}
diff --git a/compiler/forget/src/__tests__/fixtures/compiler/array-property-call.expect.md b/compiler/forget/src/__tests__/fixtures/compiler/array-property-call.expect.md
new file mode 100644
index 0000000000..8f897264d4
--- /dev/null
+++ b/compiler/forget/src/__tests__/fixtures/compiler/array-property-call.expect.md
@@ -0,0 +1,59 @@
+
+## Input
+
+```javascript
+function Component(props) {
+  const a = [props.a, props.b, "hello"];
+  const x = a.push(42);
+  const y = a.at(props.c);
+
+  return { a, x, y };
+}
+
+```
+
+## Code
+
+```javascript
+function Component(props) {
+  const $ = React.unstable_useMemoCache(10);
+  const c_0 = $[0] !== props.a;
+  const c_1 = $[1] !== props.b;
+  const c_2 = $[2] !== props.c;
+  let t0;
+  let a;
+  let x;
+  if (c_0 || c_1 || c_2) {
+    a = [props.a, props.b, "hello"];
+    x = a.push(42);
+    t0 = a.at(props.c);
+    $[0] = props.a;
+    $[1] = props.b;
+    $[2] = props.c;
+    $[3] = t0;
+    $[4] = a;
+    $[5] = x;
+  } else {
+    t0 = $[3];
+    a = $[4];
+    x = $[5];
+  }
+  const y = t0;
+  const c_6 = $[6] !== a;
+  const c_7 = $[7] !== x;
+  const c_8 = $[8] !== y;
+  let t1;
+  if (c_6 || c_7 || c_8) {
+    t1 = { a, x, y };
+    $[6] = a;
+    $[7] = x;
+    $[8] = y;
+    $[9] = t1;
+  } else {
+    t1 = $[9];
+  }
+  return t1;
+}
+
+```
+      
\ No newline at end of file
diff --git a/compiler/forget/src/__tests__/fixtures/compiler/array-property-call.js b/compiler/forget/src/__tests__/fixtures/compiler/array-property-call.js
new file mode 100644
index 0000000000..3356a23cd6
--- /dev/null
+++ b/compiler/forget/src/__tests__/fixtures/compiler/array-property-call.js
@@ -0,0 +1,7 @@
+function Component(props) {
+  const a = [props.a, props.b, "hello"];
+  const x = a.push(42);
+  const y = a.at(props.c);
+
+  return { a, x, y };
+}
diff --git a/compiler/forget/src/__tests__/fixtures/hir/array-properties.expect.md b/compiler/forget/src/__tests__/fixtures/hir/array-properties.expect.md
new file mode 100644
index 0000000000..975aabd471
--- /dev/null
+++ b/compiler/forget/src/__tests__/fixtures/hir/array-properties.expect.md
@@ -0,0 +1,39 @@
+
+## Input
+
+```javascript
+function Component(props) {
+  const a = [props.a, props.b, "hello"];
+  const x = a.length;
+  const y = a.push;
+  return { a, x, y, z: a.concat };
+}
+
+```
+
+## HIR
+
+```javascript
+bb0 (block):
+  [1] mutate $25 = LoadLocal read props$24
+  [2] mutate $26 = PropertyLoad read $25.a
+  [3] mutate $27 = LoadLocal read props$24
+  [4] mutate $28 = PropertyLoad read $27.b
+  [5] mutate $29:TPrimitive = "hello"
+  [6] store $30:TObject<Array> = Array [read $26, read $28, read $29:TPrimitive]
+  [7] store $32:TObject<Array> = StoreLocal Const store a$31:TObject<Array> = capture $30:TObject<Array>
+  [8] mutate $33:TObject<Array> = LoadLocal capture a$31:TObject<Array>
+  [9] mutate $34:TPrimitive = PropertyLoad read $33:TObject<Array>.length
+  [10] store $36:TPrimitive = StoreLocal Const mutate x$35:TPrimitive = capture $34:TPrimitive
+  [11] mutate $37:TObject<Array> = LoadLocal capture a$31:TObject<Array>
+  [12] mutate $38:TFunction<<generated_2>> = PropertyLoad read $37:TObject<Array>.push
+  [13] store $40:TFunction<<generated_2>> = StoreLocal Const mutate y$39:TFunction<<generated_2>> = capture $38:TFunction<<generated_2>>
+  [14] mutate $41:TObject<Array> = LoadLocal capture a$31:TObject<Array>
+  [15] mutate $42:TPrimitive = LoadLocal capture x$35:TPrimitive
+  [16] mutate $43:TFunction<<generated_2>> = LoadLocal capture y$39:TFunction<<generated_2>>
+  [17] mutate $44:TObject<Array> = LoadLocal capture a$31:TObject<Array>
+  [18] mutate $45:TFunction<<generated_1>> = PropertyLoad read $44:TObject<Array>.concat
+  [19] store $46:TObject<Object> = Object { a: capture $41:TObject<Array>, x: capture $42:TPrimitive, y: capture $43:TFunction<<generated_2>>, z: capture $45:TFunction<<generated_1>> }
+  [20] Return freeze $46:TObject<Object>
+```
+      
\ No newline at end of file
diff --git a/compiler/forget/src/__tests__/fixtures/hir/array-properties.js b/compiler/forget/src/__tests__/fixtures/hir/array-properties.js
new file mode 100644
index 0000000000..8d314feb33
--- /dev/null
+++ b/compiler/forget/src/__tests__/fixtures/hir/array-properties.js
@@ -0,0 +1,6 @@
+function Component(props) {
+  const a = [props.a, props.b, "hello"];
+  const x = a.length;
+  const y = a.push;
+  return { a, x, y, z: a.concat };
+}
diff --git a/compiler/forget/src/__tests__/fixtures/hir/array-property-call.expect.md b/compiler/forget/src/__tests__/fixtures/hir/array-property-call.expect.md
new file mode 100644
index 0000000000..bad8635364
--- /dev/null
+++ b/compiler/forget/src/__tests__/fixtures/hir/array-property-call.expect.md
@@ -0,0 +1,43 @@
+
+## Input
+
+```javascript
+function Component(props) {
+  const a = [props.a, props.b, "hello"];
+  const x = a.push(42);
+  const y = a.at(props.c);
+
+  return { a, x, y };
+}
+
+```
+
+## HIR
+
+```javascript
+bb0 (block):
+  [1] mutate $28 = LoadLocal read props$27
+  [2] mutate $29 = PropertyLoad read $28.a
+  [3] mutate $30 = LoadLocal read props$27
+  [4] mutate $31 = PropertyLoad read $30.b
+  [5] mutate $32:TPrimitive = "hello"
+  [6] store $33[6:18]:TObject<Array> = Array [read $29, read $31, read $32:TPrimitive]
+  [7] store $35[7:18]:TObject<Array> = StoreLocal Const store a$34[7:18]:TObject<Array> = capture $33[6:18]:TObject<Array>
+  [8] mutate $36[8:18]:TObject<Array> = LoadLocal capture a$34[7:18]:TObject<Array>
+  [9] mutate $37:TPrimitive = 42
+  [10] mutate $38[10:18]:TFunction<<generated_2>> = PropertyLoad read $36[8:18]:TObject<Array>.push
+  [11] mutate $39:TPrimitive = PropertyCall mutate $36[8:18]:TObject<Array>.read $38[10:18]:TFunction<<generated_2>>(read $37:TPrimitive)
+  [12] store $41:TPrimitive = StoreLocal Const mutate x$40:TPrimitive = capture $39:TPrimitive
+  [13] mutate $42[13:18]:TObject<Array> = LoadLocal capture a$34[7:18]:TObject<Array>
+  [14] mutate $43 = LoadLocal read props$27
+  [15] mutate $44 = PropertyLoad read $43.c
+  [16] mutate $45[16:18]:TFunction<<generated_0>> = PropertyLoad read $42[13:18]:TObject<Array>.at
+  [17] mutate $46 = PropertyCall mutate $42[13:18]:TObject<Array>.read $45[16:18]:TFunction<<generated_0>>(read $44)
+  [18] store $48 = StoreLocal Const mutate y$47 = capture $46
+  [19] mutate $49:TObject<Array> = LoadLocal capture a$34[7:18]:TObject<Array>
+  [20] mutate $50:TPrimitive = LoadLocal capture x$40:TPrimitive
+  [21] mutate $51 = LoadLocal capture y$47
+  [22] store $52:TObject<Object> = Object { a: capture $49:TObject<Array>, x: capture $50:TPrimitive, y: capture $51 }
+  [23] Return freeze $52:TObject<Object>
+```
+      
\ No newline at end of file
diff --git a/compiler/forget/src/__tests__/fixtures/hir/array-property-call.js b/compiler/forget/src/__tests__/fixtures/hir/array-property-call.js
new file mode 100644
index 0000000000..3356a23cd6
--- /dev/null
+++ b/compiler/forget/src/__tests__/fixtures/hir/array-property-call.js
@@ -0,0 +1,7 @@
+function Component(props) {
+  const a = [props.a, props.b, "hello"];
+  const x = a.push(42);
+  const y = a.at(props.c);
+
+  return { a, x, y };
+}
diff --git a/compiler/forget/src/__tests__/fixtures/hir/infer-call-array-length.expect.md b/compiler/forget/src/__tests__/fixtures/hir/infer-call-array-length.expect.md
new file mode 100644
index 0000000000..7506aac791
--- /dev/null
+++ b/compiler/forget/src/__tests__/fixtures/hir/infer-call-array-length.expect.md
@@ -0,0 +1,26 @@
+
+## Input
+
+```javascript
+function Component() {
+  let x = [];
+  let y = x.length();
+  return y;
+}
+
+```
+
+## HIR
+
+```javascript
+bb0 (block):
+  [1] store $10[1:6]:TObject<Array> = Array []
+  [2] store $12[2:6]:TObject<Array> = StoreLocal Const store x$11[2:6]:TObject<Array> = capture $10[1:6]:TObject<Array>
+  [3] mutate $13[3:6]:TObject<Array> = LoadLocal capture x$11[2:6]:TObject<Array>
+  [4] mutate $14[4:6]:TPrimitive = PropertyLoad read $13[3:6]:TObject<Array>.length
+  [5] mutate $15 = PropertyCall mutate $13[3:6]:TObject<Array>.read $14[4:6]:TPrimitive()
+  [6] store $17 = StoreLocal Const mutate y$16 = capture $15
+  [7] mutate $18 = LoadLocal capture y$16
+  [8] Return freeze $18
+```
+      
\ No newline at end of file
diff --git a/compiler/forget/src/__tests__/fixtures/hir/infer-call-array-length.js b/compiler/forget/src/__tests__/fixtures/hir/infer-call-array-length.js
new file mode 100644
index 0000000000..6aa8841509
--- /dev/null
+++ b/compiler/forget/src/__tests__/fixtures/hir/infer-call-array-length.js
@@ -0,0 +1,5 @@
+function Component() {
+  let x = [];
+  let y = x.length();
+  return y;
+}
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary-destruction-with-mutation.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary-destruction-with-mutation.expect.md
index 12a39cb391..9fd4956180 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary-destruction-with-mutation.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary-destruction-with-mutation.expect.md
@@ -24,8 +24,8 @@ bb0 (block):
   [3] mutate $41[3:36]:TObject<Array> = LoadLocal capture x$39[2:36]:TObject<Array>
   [4] mutate $42 = LoadLocal read props$37
   [5] mutate $43 = PropertyLoad read $42.bar
-  [6] mutate $44[6:36] = PropertyLoad read $41[3:36]:TObject<Array>.push
-  [7] mutate $45 = PropertyCall mutate $41[3:36]:TObject<Array>.[object Object](read $43)
+  [6] mutate $44[6:36]:TFunction<<generated_2>> = PropertyLoad read $41[3:36]:TObject<Array>.push
+  [7] mutate $45:TPrimitive = PropertyCall mutate $41[3:36]:TObject<Array>.read $44[6:36]:TFunction<<generated_2>>(read $43)
   [8] Ternary test:bb2 fallthrough=bb1
 bb2 (value):
   predecessor blocks: bb0
@@ -41,7 +41,7 @@ bb3 (value):
   [19] mutate $57 = LoadLocal read props$37
   [20] mutate $58 = PropertyLoad read $57.foo
   [21] mutate $59[21:36] = PropertyLoad read $56[18:36].push
-  [22] mutate $60[22:33] = PropertyCall mutate $56[18:36].[object Object](read $58)
+  [22] mutate $60[22:33] = PropertyCall mutate $56[18:36].read $59[21:36](read $58)
   [23] store $62[23:33] = StoreLocal Const mutate $61[8:33] = capture $60[22:33]
   [24] Goto bb1
 bb4 (value):
@@ -57,7 +57,7 @@ bb1 (block):
   [29] mutate $69 = Global console
   [30] mutate $70[30:33] = LoadLocal capture _$66[28:33]
   [31] mutate $71 = PropertyLoad read $69.log
-  [32] mutate $72 = PropertyCall read $69.[object Object](mutate $70[30:33])
+  [32] mutate $72 = PropertyCall read $69.read $71(mutate $70[30:33])
   [33] mutate $73:TFunction = Global mut
   [34] mutate $74[34:36] = LoadLocal capture x$39[2:36]
   [35] mutate $76 = Call read $73:TFunction(mutate $74[34:36])
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary-destruction.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary-destruction.expect.md
index 8b65c73c61..b143a7e0af 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary-destruction.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary-destruction.expect.md
@@ -23,8 +23,8 @@ bb0 (block):
   [3] mutate $38[3:8]:TObject<Array> = LoadLocal capture x$36[2:8]:TObject<Array>
   [4] mutate $39 = LoadLocal read props$34
   [5] mutate $40 = PropertyLoad read $39.bar
-  [6] mutate $41[6:8] = PropertyLoad read $38[3:8]:TObject<Array>.push
-  [7] mutate $42 = PropertyCall mutate $38[3:8]:TObject<Array>.[object Object](read $40)
+  [6] mutate $41[6:8]:TFunction<<generated_2>> = PropertyLoad read $38[3:8]:TObject<Array>.push
+  [7] mutate $42:TPrimitive = PropertyCall mutate $38[3:8]:TObject<Array>.read $41[6:8]:TFunction<<generated_2>>(read $40)
   [8] Ternary test:bb2 fallthrough=bb1
 bb2 (value):
   predecessor blocks: bb0
@@ -40,7 +40,7 @@ bb3 (value):
   [19] mutate $54 = LoadLocal read props$34
   [20] mutate $55 = PropertyLoad read $54.foo
   [21] mutate $56[21:23] = PropertyLoad read $53[18:23].push
-  [22] mutate $57[22:33] = PropertyCall mutate $53[18:23].[object Object](read $55)
+  [22] mutate $57[22:33] = PropertyCall mutate $53[18:23].read $56[21:23](read $55)
   [23] store $59[23:33] = StoreLocal Const mutate $58[8:33] = capture $57[22:33]
   [24] Goto bb1
 bb4 (value):
@@ -56,7 +56,7 @@ bb1 (block):
   [29] mutate $66 = Global console
   [30] mutate $67[30:33] = LoadLocal capture _$63[28:33]
   [31] mutate $68 = PropertyLoad read $66.log
-  [32] mutate $69 = PropertyCall read $66.[object Object](mutate $67[30:33])
+  [32] mutate $69 = PropertyCall read $66.read $68(mutate $67[30:33])
   [33] mutate $70 = LoadLocal capture x$36
   [34] Return freeze $70
 ```
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary-with-mutation.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary-with-mutation.expect.md
index a94dc61094..d6ebe2504c 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary-with-mutation.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary-with-mutation.expect.md
@@ -22,8 +22,8 @@ bb0 (block):
   [3] mutate $39[3:34]:TObject<Array> = LoadLocal capture x$37[2:34]:TObject<Array>
   [4] mutate $40 = LoadLocal read props$35
   [5] mutate $41 = PropertyLoad read $40.bar
-  [6] mutate $42[6:34] = PropertyLoad read $39[3:34]:TObject<Array>.push
-  [7] mutate $43 = PropertyCall mutate $39[3:34]:TObject<Array>.[object Object](read $41)
+  [6] mutate $42[6:34]:TFunction<<generated_2>> = PropertyLoad read $39[3:34]:TObject<Array>.push
+  [7] mutate $43:TPrimitive = PropertyCall mutate $39[3:34]:TObject<Array>.read $42[6:34]:TFunction<<generated_2>>(read $41)
   [8] Ternary test:bb2 fallthrough=bb1
 bb2 (value):
   predecessor blocks: bb0
@@ -37,24 +37,24 @@ bb3 (value):
   [16] mutate $52[16:34]:TObject<Array> = LoadLocal capture x$37[15:34]:TObject<Array>
   [17] mutate $53 = LoadLocal read props$35
   [18] mutate $54 = PropertyLoad read $53.foo
-  [19] mutate $55[19:34] = PropertyLoad read $52[16:34]:TObject<Array>.push
-  [20] mutate $56[20:31] = PropertyCall mutate $52[16:34]:TObject<Array>.[object Object](read $54)
-  [21] store $58[21:31] = StoreLocal Const mutate $57[8:31] = capture $56[20:31]
+  [19] mutate $55[19:34]:TFunction<<generated_2>> = PropertyLoad read $52[16:34]:TObject<Array>.push
+  [20] mutate $56[20:31]:TPrimitive = PropertyCall mutate $52[16:34]:TObject<Array>.read $55[19:34]:TFunction<<generated_2>>(read $54)
+  [21] store $58[21:31]:TPrimitive = StoreLocal Const mutate $57[8:31]:TPrimitive = capture $56[20:31]:TPrimitive
   [22] Goto bb1
 bb4 (value):
   predecessor blocks: bb2
   [23] mutate $59[23:31]:TPrimitive = null
-  [24] store $61[24:31]:TPrimitive = StoreLocal Const mutate $57[8:31] = read $59[23:31]:TPrimitive
+  [24] store $61[24:31]:TPrimitive = StoreLocal Const mutate $57[8:31]:TPrimitive = read $59[23:31]:TPrimitive
   [25] Goto bb1
 bb1 (block):
   predecessor blocks: bb3 bb4
-  $64[8:31]:TPhi: phi(bb3: $57, bb4: $60)
+  $64[8:31]:TPrimitive: phi(bb3: $57, bb4: $60)
   x$37[2:34]:TObject<Array>: phi(bb3: x$37, bb4: x$37)
-  [26] store $63[26:31] = StoreLocal Const mutate _$62[26:31] = capture $57[8:31]
+  [26] store $63[26:31] = StoreLocal Const mutate _$62[26:31] = capture $57[8:31]:TPrimitive
   [27] mutate $65 = Global console
   [28] mutate $66[28:31] = LoadLocal capture _$62[26:31]
   [29] mutate $67 = PropertyLoad read $65.log
-  [30] mutate $68 = PropertyCall read $65.[object Object](mutate $66[28:31])
+  [30] mutate $68 = PropertyCall read $65.read $67(mutate $66[28:31])
   [31] mutate $69:TFunction = Global mut
   [32] mutate $70[32:34] = LoadLocal capture x$37[2:34]
   [33] mutate $72 = Call read $69:TFunction(mutate $70[32:34])
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary.expect.md
index 9673cf7507..b4b9d37e8e 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-ternary.expect.md
@@ -21,8 +21,8 @@ bb0 (block):
   [3] mutate $36[3:8]:TObject<Array> = LoadLocal capture x$34[2:8]:TObject<Array>
   [4] mutate $37 = LoadLocal read props$32
   [5] mutate $38 = PropertyLoad read $37.bar
-  [6] mutate $39[6:8] = PropertyLoad read $36[3:8]:TObject<Array>.push
-  [7] mutate $40 = PropertyCall mutate $36[3:8]:TObject<Array>.[object Object](read $38)
+  [6] mutate $39[6:8]:TFunction<<generated_2>> = PropertyLoad read $36[3:8]:TObject<Array>.push
+  [7] mutate $40:TPrimitive = PropertyCall mutate $36[3:8]:TObject<Array>.read $39[6:8]:TFunction<<generated_2>>(read $38)
   [8] Ternary test:bb2 fallthrough=bb1
 bb2 (value):
   predecessor blocks: bb0
@@ -36,24 +36,24 @@ bb3 (value):
   [16] mutate $49[16:21]:TObject<Array> = LoadLocal capture x$34[15:21]:TObject<Array>
   [17] mutate $50 = LoadLocal read props$32
   [18] mutate $51 = PropertyLoad read $50.foo
-  [19] mutate $52[19:21] = PropertyLoad read $49[16:21]:TObject<Array>.push
-  [20] mutate $53[20:31] = PropertyCall mutate $49[16:21]:TObject<Array>.[object Object](read $51)
-  [21] store $55[21:31] = StoreLocal Const mutate $54[8:31] = capture $53[20:31]
+  [19] mutate $52[19:21]:TFunction<<generated_2>> = PropertyLoad read $49[16:21]:TObject<Array>.push
+  [20] mutate $53[20:31]:TPrimitive = PropertyCall mutate $49[16:21]:TObject<Array>.read $52[19:21]:TFunction<<generated_2>>(read $51)
+  [21] store $55[21:31]:TPrimitive = StoreLocal Const mutate $54[8:31]:TPrimitive = capture $53[20:31]:TPrimitive
   [22] Goto bb1
 bb4 (value):
   predecessor blocks: bb2
   [23] mutate $56[23:31]:TPrimitive = null
-  [24] store $58[24:31]:TPrimitive = StoreLocal Const mutate $54[8:31] = read $56[23:31]:TPrimitive
+  [24] store $58[24:31]:TPrimitive = StoreLocal Const mutate $54[8:31]:TPrimitive = read $56[23:31]:TPrimitive
   [25] Goto bb1
 bb1 (block):
   predecessor blocks: bb3 bb4
-  $61[8:31]:TPhi: phi(bb3: $54, bb4: $57)
+  $61[8:31]:TPrimitive: phi(bb3: $54, bb4: $57)
   x$34:TObject<Array>: phi(bb3: x$34, bb4: x$34)
-  [26] store $60[26:31] = StoreLocal Const mutate _$59[26:31] = capture $54[8:31]
+  [26] store $60[26:31] = StoreLocal Const mutate _$59[26:31] = capture $54[8:31]:TPrimitive
   [27] mutate $62 = Global console
   [28] mutate $63[28:31] = LoadLocal capture _$59[26:31]
   [29] mutate $64 = PropertyLoad read $62.log
-  [30] mutate $65 = PropertyCall read $62.[object Object](mutate $63[28:31])
+  [30] mutate $65 = PropertyCall read $62.read $64(mutate $63[28:31])
   [31] mutate $66 = LoadLocal capture x$34
   [32] Return freeze $66
 ```
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-unconditional-ternary-with-mutation.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-unconditional-ternary-with-mutation.expect.md
index 935b927313..7ed9278fa3 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-unconditional-ternary-with-mutation.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-unconditional-ternary-with-mutation.expect.md
@@ -24,8 +24,8 @@ bb0 (block):
   [3] mutate $47[3:8]:TObject<Array> = LoadLocal capture x$45[2:42]:TObject<Array>
   [4] mutate $48 = LoadLocal read props$43
   [5] mutate $49 = PropertyLoad read $48.bar
-  [6] mutate $50[6:8] = PropertyLoad read $47[3:8]:TObject<Array>.push
-  [7] mutate $51 = PropertyCall mutate $47[3:8]:TObject<Array>.[object Object](read $49)
+  [6] mutate $50[6:8]:TFunction<<generated_2>> = PropertyLoad read $47[3:8]:TObject<Array>.push
+  [7] mutate $51:TPrimitive = PropertyCall mutate $47[3:8]:TObject<Array>.read $50[6:8]:TFunction<<generated_2>>(read $49)
   [8] Ternary test:bb2 fallthrough=bb1
 bb2 (value):
   predecessor blocks: bb0
@@ -39,9 +39,9 @@ bb3 (value):
   [16] mutate $60[16:42]:TObject<Array> = LoadLocal capture x$45[15:42]:TObject<Array>
   [17] mutate $61 = LoadLocal read props$43
   [18] mutate $62 = PropertyLoad read $61.foo
-  [19] mutate $63[19:42] = PropertyLoad read $60[16:42]:TObject<Array>.push
-  [20] mutate $64[20:39] = PropertyCall mutate $60[16:42]:TObject<Array>.[object Object](read $62)
-  [21] store $66[21:39] = StoreLocal Const mutate $65[8:39] = capture $64[20:39]
+  [19] mutate $63[19:42]:TFunction<<generated_2>> = PropertyLoad read $60[16:42]:TObject<Array>.push
+  [20] mutate $64[20:39]:TPrimitive = PropertyCall mutate $60[16:42]:TObject<Array>.read $63[19:42]:TFunction<<generated_2>>(read $62)
+  [21] store $66[21:39]:TPrimitive = StoreLocal Const mutate $65[8:39]:TPrimitive = capture $64[20:39]:TPrimitive
   [22] Goto bb1
 bb4 (value):
   predecessor blocks: bb2
@@ -50,19 +50,19 @@ bb4 (value):
   [27] mutate $73[27:42]:TObject<Array> = LoadLocal capture x$45[26:42]:TObject<Array>
   [28] mutate $74 = LoadLocal read props$43
   [29] mutate $75 = PropertyLoad read $74.bar
-  [30] mutate $76[30:42] = PropertyLoad read $73[27:42]:TObject<Array>.push
-  [31] mutate $77[31:39] = PropertyCall mutate $73[27:42]:TObject<Array>.[object Object](read $75)
-  [32] store $79[32:39] = StoreLocal Const mutate $65[8:39] = capture $77[31:39]
+  [30] mutate $76[30:42]:TFunction<<generated_2>> = PropertyLoad read $73[27:42]:TObject<Array>.push
+  [31] mutate $77[31:39]:TPrimitive = PropertyCall mutate $73[27:42]:TObject<Array>.read $76[30:42]:TFunction<<generated_2>>(read $75)
+  [32] store $79[32:39]:TPrimitive = StoreLocal Const mutate $65[8:39]:TPrimitive = capture $77[31:39]:TPrimitive
   [33] Goto bb1
 bb1 (block):
   predecessor blocks: bb3 bb4
-  $82[8:39]:TPhi: phi(bb3: $65, bb4: $78)
+  $82[8:39]:TPrimitive: phi(bb3: $65, bb4: $78)
   x$45[15:42]:TObject<Array>: phi(bb3: x$45, bb4: x$45)
-  [34] store $81[34:39] = StoreLocal Const mutate _$80[34:39] = capture $65[8:39]
+  [34] store $81[34:39] = StoreLocal Const mutate _$80[34:39] = capture $65[8:39]:TPrimitive
   [35] mutate $83 = Global console
   [36] mutate $84[36:39] = LoadLocal capture _$80[34:39]
   [37] mutate $85 = PropertyLoad read $83.log
-  [38] mutate $86 = PropertyCall read $83.[object Object](mutate $84[36:39])
+  [38] mutate $86 = PropertyCall read $83.read $85(mutate $84[36:39])
   [39] mutate $87:TFunction = Global mut
   [40] mutate $88[40:42] = LoadLocal capture x$45[15:42]
   [41] mutate $90 = Call read $87:TFunction(mutate $88[40:42])
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-unconditional-ternary.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-unconditional-ternary.expect.md
index 1ce2d98123..5562e58710 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-unconditional-ternary.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-unconditional-ternary.expect.md
@@ -23,8 +23,8 @@ bb0 (block):
   [3] mutate $44[3:8]:TObject<Array> = LoadLocal capture x$42[2:8]:TObject<Array>
   [4] mutate $45 = LoadLocal read props$40
   [5] mutate $46 = PropertyLoad read $45.bar
-  [6] mutate $47[6:8] = PropertyLoad read $44[3:8]:TObject<Array>.push
-  [7] mutate $48 = PropertyCall mutate $44[3:8]:TObject<Array>.[object Object](read $46)
+  [6] mutate $47[6:8]:TFunction<<generated_2>> = PropertyLoad read $44[3:8]:TObject<Array>.push
+  [7] mutate $48:TPrimitive = PropertyCall mutate $44[3:8]:TObject<Array>.read $47[6:8]:TFunction<<generated_2>>(read $46)
   [8] Ternary test:bb2 fallthrough=bb1
 bb2 (value):
   predecessor blocks: bb0
@@ -38,9 +38,9 @@ bb3 (value):
   [16] mutate $57[16:21]:TObject<Array> = LoadLocal capture x$42[15:21]:TObject<Array>
   [17] mutate $58 = LoadLocal read props$40
   [18] mutate $59 = PropertyLoad read $58.foo
-  [19] mutate $60[19:21] = PropertyLoad read $57[16:21]:TObject<Array>.push
-  [20] mutate $61[20:39] = PropertyCall mutate $57[16:21]:TObject<Array>.[object Object](read $59)
-  [21] store $63[21:39] = StoreLocal Const mutate $62[8:39] = capture $61[20:39]
+  [19] mutate $60[19:21]:TFunction<<generated_2>> = PropertyLoad read $57[16:21]:TObject<Array>.push
+  [20] mutate $61[20:39]:TPrimitive = PropertyCall mutate $57[16:21]:TObject<Array>.read $60[19:21]:TFunction<<generated_2>>(read $59)
+  [21] store $63[21:39]:TPrimitive = StoreLocal Const mutate $62[8:39]:TPrimitive = capture $61[20:39]:TPrimitive
   [22] Goto bb1
 bb4 (value):
   predecessor blocks: bb2
@@ -49,19 +49,19 @@ bb4 (value):
   [27] mutate $70[27:32]:TObject<Array> = LoadLocal capture x$42[26:32]:TObject<Array>
   [28] mutate $71 = LoadLocal read props$40
   [29] mutate $72 = PropertyLoad read $71.bar
-  [30] mutate $73[30:32] = PropertyLoad read $70[27:32]:TObject<Array>.push
-  [31] mutate $74[31:39] = PropertyCall mutate $70[27:32]:TObject<Array>.[object Object](read $72)
-  [32] store $76[32:39] = StoreLocal Const mutate $62[8:39] = capture $74[31:39]
+  [30] mutate $73[30:32]:TFunction<<generated_2>> = PropertyLoad read $70[27:32]:TObject<Array>.push
+  [31] mutate $74[31:39]:TPrimitive = PropertyCall mutate $70[27:32]:TObject<Array>.read $73[30:32]:TFunction<<generated_2>>(read $72)
+  [32] store $76[32:39]:TPrimitive = StoreLocal Const mutate $62[8:39]:TPrimitive = capture $74[31:39]:TPrimitive
   [33] Goto bb1
 bb1 (block):
   predecessor blocks: bb3 bb4
-  $79[8:39]:TPhi: phi(bb3: $62, bb4: $75)
+  $79[8:39]:TPrimitive: phi(bb3: $62, bb4: $75)
   x$42:TObject<Array>: phi(bb3: x$42, bb4: x$42)
-  [34] store $78[34:39] = StoreLocal Const mutate _$77[34:39] = capture $62[8:39]
+  [34] store $78[34:39] = StoreLocal Const mutate _$77[34:39] = capture $62[8:39]:TPrimitive
   [35] mutate $80 = Global console
   [36] mutate $81[36:39] = LoadLocal capture _$77[34:39]
   [37] mutate $82 = PropertyLoad read $80.log
-  [38] mutate $83 = PropertyCall read $80.[object Object](mutate $81[36:39])
+  [38] mutate $83 = PropertyCall read $80.read $82(mutate $81[36:39])
   [39] mutate $84 = LoadLocal capture x$42
   [40] Return freeze $84
 ```
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-unconditional-with-mutation.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-unconditional-with-mutation.expect.md
index 54d561135c..625e980712 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-unconditional-with-mutation.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-renaming-unconditional-with-mutation.expect.md
@@ -29,8 +29,8 @@ bb0 (block):
   [3] mutate $38[3:8]:TObject<Array> = LoadLocal capture x$36[2:34]:TObject<Array>
   [4] mutate $39 = LoadLocal read props$34
   [5] mutate $40 = PropertyLoad read $39.bar
-  [6] mutate $41[6:8] = PropertyLoad read $38[3:8]:TObject<Array>.push
-  [7] mutate $42 = PropertyCall mutate $38[3:8]:TObject<Array>.[object Object](read $40)
+  [6] mutate $41[6:8]:TFunction<<generated_2>> = PropertyLoad read $38[3:8]:TObject<Array>.push
+  [7] mutate $42:TPrimitive = PropertyCall mutate $38[3:8]:TObject<Array>.read $41[6:8]:TFunction<<generated_2>>(read $40)
   [8] mutate $43 = LoadLocal read props$34
   [9] mutate $44 = PropertyLoad read $43.cond
   [10] If (read $44) then:bb2 else:bb3 fallthrough=bb1
@@ -41,8 +41,8 @@ bb2 (block):
   [15] mutate $51[15:34]:TObject<Array> = LoadLocal capture x$36[14:34]:TObject<Array>
   [16] mutate $52 = LoadLocal read props$34
   [17] mutate $53 = PropertyLoad read $52.foo
-  [18] mutate $54[18:34] = PropertyLoad read $51[15:34]:TObject<Array>.push
-  [19] mutate $55 = PropertyCall mutate $51[15:34]:TObject<Array>.[object Object](read $53)
+  [18] mutate $54[18:34]:TFunction<<generated_2>> = PropertyLoad read $51[15:34]:TObject<Array>.push
+  [19] mutate $55:TPrimitive = PropertyCall mutate $51[15:34]:TObject<Array>.read $54[18:34]:TFunction<<generated_2>>(read $53)
   [20] Goto bb1
 bb3 (block):
   predecessor blocks: bb0
@@ -51,8 +51,8 @@ bb3 (block):
   [25] mutate $62[25:34]:TObject<Array> = LoadLocal capture x$36[24:34]:TObject<Array>
   [26] mutate $63 = LoadLocal read props$34
   [27] mutate $64 = PropertyLoad read $63.bar
-  [28] mutate $65[28:34] = PropertyLoad read $62[25:34]:TObject<Array>.push
-  [29] mutate $66 = PropertyCall mutate $62[25:34]:TObject<Array>.[object Object](read $64)
+  [28] mutate $65[28:34]:TFunction<<generated_2>> = PropertyLoad read $62[25:34]:TObject<Array>.push
+  [29] mutate $66:TPrimitive = PropertyCall mutate $62[25:34]:TObject<Array>.read $65[28:34]:TFunction<<generated_2>>(read $64)
   [30] Goto bb1
 bb1 (block):
   predecessor blocks: bb2 bb3