diff --git a/crates/oxide_compiler/src/compiler.rs b/crates/oxide_compiler/src/compiler.rs
index 0c09b3e..f272696 100644
--- a/crates/oxide_compiler/src/compiler.rs
+++ b/crates/oxide_compiler/src/compiler.rs
@@ -302,6 +302,39 @@ impl CompileCtx {
             "parseFloat",
             "isNaN",
             "isFinite",
+            // Out-of-scope constructors: bound as TypeError-throwing stubs
+            "Proxy",
+            "WeakMap",
+            "WeakSet",
+            "WeakRef",
+            "FinalizationRegistry",
+            "Atomics",
+            "SharedArrayBuffer",
+            "ArrayBuffer",
+            "DataView",
+            "Iterator",
+            "BigInt",
+            // TypedArray family stubs
+            "Int8Array",
+            "Uint8Array",
+            "Uint8ClampedArray",
+            "Int16Array",
+            "Uint16Array",
+            "Int32Array",
+            "Uint32Array",
+            "Float32Array",
+            "Float64Array",
+            "BigInt64Array",
+            "BigUint64Array",
+            // Reflect namespace object
+            "Reflect",
+            // URI utility functions
+            "escape",
+            "unescape",
+            "encodeURI",
+            "decodeURI",
+            "encodeURIComponent",
+            "decodeURIComponent",
         ];
         for name in &builtins {
             let reg = self.alloc_reg();
diff --git a/crates/oxide_vm/src/builtins/mod.rs b/crates/oxide_vm/src/builtins/mod.rs
index 36d4e3c..e581bbc 100644
--- a/crates/oxide_vm/src/builtins/mod.rs
+++ b/crates/oxide_vm/src/builtins/mod.rs
@@ -12,4 +12,5 @@ pub mod object;
 pub mod regexp;
 pub mod set;
 pub mod string;
+pub mod stubs;
 pub mod symbol;
diff --git a/crates/oxide_vm/src/builtins/stubs.rs b/crates/oxide_vm/src/builtins/stubs.rs
new file mode 100644
index 0000000..28bd46b
--- /dev/null
+++ b/crates/oxide_vm/src/builtins/stubs.rs
@@ -0,0 +1,20 @@
+use oxide_types::value::JsValue;
+
+use crate::native::NativeResult;
+use crate::vm::Vm;
+
+fn stub_error(vm: &mut Vm, name: &str) -> NativeResult {
+    let msg = format!("TypeError: {} is not implemented", name);
+    let si = vm.kernel_core().string_forge().intern(&msg).0;
+    NativeResult::Err(JsValue::string(si, 0))
+}
+
+// Architecturally deferred — see 13.5-CONTEXT.md for rationale
+pub fn proxy_stub(vm: &mut Vm, _args: &[u8]) -> NativeResult { stub_error(vm, "Proxy") }
+pub fn bigint_stub(vm: &mut Vm, _args: &[u8]) -> NativeResult { stub_error(vm, "BigInt") }
+pub fn weakmap_stub(vm: &mut Vm, _args: &[u8]) -> NativeResult { stub_error(vm, "WeakMap") }
+pub fn weakset_stub(vm: &mut Vm, _args: &[u8]) -> NativeResult { stub_error(vm, "WeakSet") }
+pub fn weakref_stub(vm: &mut Vm, _args: &[u8]) -> NativeResult { stub_error(vm, "WeakRef") }
+pub fn finalization_registry_stub(vm: &mut Vm, _args: &[u8]) -> NativeResult { stub_error(vm, "FinalizationRegistry") }
+pub fn shared_array_buffer_stub(vm: &mut Vm, _args: &[u8]) -> NativeResult { stub_error(vm, "SharedArrayBuffer") }
+pub fn atomics_stub(vm: &mut Vm, _args: &[u8]) -> NativeResult { stub_error(vm, "Atomics") }