diff --git a/Cargo.lock b/Cargo.lock
index 67ada84c..5b2773f9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1101,6 +1101,14 @@ dependencies = [
  "oxc_syntax",
 ]
 
+[[package]]
+name = "oxide_runtime_api"
+version = "0.1.0"
+dependencies = [
+ "oxide_kernel",
+ "oxide_types",
+]
+
 [[package]]
 name = "oxide_test262"
 version = "0.1.0"
@@ -1139,6 +1147,7 @@ dependencies = [
  "oxide_compiler",
  "oxide_kernel",
  "oxide_parser",
+ "oxide_runtime_api",
  "oxide_types",
  "proptest",
  "regex",
diff --git a/Cargo.toml b/Cargo.toml
index 6e83ad8a..71a4b20b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -8,6 +8,7 @@ members = [
     "crates/oxide_types",
     "crates/oxide_vm",
     "crates/oxide_kernel",
+    "crates/oxide_runtime_api",
     "crates/oxide_api",
     "crates/oxide_cli",
     "crates/oxide_test262",
diff --git a/crates/oxide_runtime_api/Cargo.toml b/crates/oxide_runtime_api/Cargo.toml
new file mode 100644
index 00000000..8d10ca32
--- /dev/null
+++ b/crates/oxide_runtime_api/Cargo.toml
@@ -0,0 +1,11 @@
+[package]
+name = "oxide_runtime_api"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+rust-version.workspace = true
+description = "OxideJS - VmHost trait: the abstract Vm interface builtins are written against"
+
+[dependencies]
+oxide_types = { path = "../oxide_types" }
+oxide_kernel = { path = "../oxide_kernel" }
diff --git a/crates/oxide_runtime_api/src/lib.rs b/crates/oxide_runtime_api/src/lib.rs
new file mode 100644
index 00000000..26fe8342
--- /dev/null
+++ b/crates/oxide_runtime_api/src/lib.rs
@@ -0,0 +1,108 @@
+//! `oxide_runtime_api` — the abstract interface between builtins and the VM.
+//!
+//! Builtins are written generically against the [`VmHost`] trait
+//! (`fn xxx<H: VmHost>(host: &mut H, args: &[u8]) -> NativeResult`); `Vm`
+//! implements `VmHost`. This breaks what would otherwise be a circular
+//! dependency between the builtins crate and `oxide_vm`:
+//!
+//! `oxide_types ← oxide_kernel ← oxide_runtime_api ← oxide_builtins ← oxide_vm`
+//!
+//! The trait is GENERIC-friendly, not object-safe: monomorphizing `H = Vm`
+//! inlines every `host.*()` call, so there is zero runtime overhead versus
+//! builtins living inside `oxide_vm`.
+
+use std::sync::Arc;
+
+use oxide_kernel::kernel::{KernelCore, KernelSession};
+use oxide_types::mem::Epoch;
+use oxide_types::object::{JsObject, PropAttributes};
+use oxide_types::value::JsValue;
+
+/// Return value of every builtin native function.
+pub enum NativeResult {
+    Ok(JsValue),
+    Err(JsValue),
+    TailCall { callee: JsValue, this: JsValue, args: Vec<JsValue> },
+}
+
+impl NativeResult {
+    pub fn ok(val: JsValue) -> Self {
+        Self::Ok(val)
+    }
+
+    pub fn err(val: JsValue) -> Self {
+        Self::Err(val)
+    }
+
+    pub fn unwrap(self) -> JsValue {
+        match self {
+            Self::Ok(val) => val,
+            Self::Err(_) => panic!("called `NativeResult::unwrap()` on an `Err` value"),
+            Self::TailCall { .. } => panic!("called `NativeResult::unwrap()` on a `TailCall` value"),
+        }
+    }
+
+    pub fn map_err<E, F>(self, op: F) -> Result<JsValue, E>
+    where
+        F: FnOnce(JsValue) -> E,
+    {
+        match self {
+            Self::Ok(val) => Ok(val),
+            Self::Err(err) => Err(op(err)),
+            Self::TailCall { .. } => panic!("TailCall cannot be converted to Result"),
+        }
+    }
+}
+
+/// The set of `Vm` capabilities that builtins depend on.
+///
+/// Signatures are byte-for-byte copies of the corresponding inherent methods on
+/// `Vm`; `impl VmHost for Vm` delegates to them. The trait is intentionally
+/// flat and not object-safe — builtins always take `&mut impl VmHost`.
+pub trait VmHost {
+    // Register access
+    fn reg(&self, idx: u8) -> JsValue;
+    fn set_reg(&mut self, idx: u8, val: JsValue);
+
+    // Object allocation / string creation
+    fn alloc_object(&mut self, obj: JsObject) -> *mut JsObject;
+    fn new_string(&mut self, s: &str) -> JsValue;
+
+    // Kernel accessors
+    fn kernel_core(&self) -> &Arc<KernelCore>;
+    fn session(&self) -> &KernelSession;
+    fn epoch(&self) -> &Epoch;
+
+    // Property resolution
+    fn property_key_si(&mut self, val: JsValue) -> u32;
+    fn resolve_property(&self, obj: &JsObject, prop_name_si: u32) -> Option<JsValue>;
+    fn get_own_property_slot(&self, obj: &JsObject, prop_name_si: u32) -> Option<u32>;
+
+    // Property access
+    fn ordinary_get(&mut self, obj: &JsObject, prop_name_si: u32, receiver: JsValue) -> Result<JsValue, String>;
+    fn ordinary_set(
+        &mut self, obj: &mut JsObject, prop_name_si: u32, val: JsValue, receiver: JsValue,
+    ) -> Result<(), String>;
+
+    // Property definition
+    fn define_data_property(
+        &mut self, obj: &mut JsObject, prop_name_si: u32, val: JsValue, attributes: PropAttributes,
+    ) -> Result<(), String>;
+    fn define_accessor_property(
+        &mut self, obj: &mut JsObject, prop_name_si: u32, get: JsValue, set: JsValue, attributes: PropAttributes,
+    ) -> Result<(), String>;
+    fn set_or_create_prop_value(&mut self, obj: &mut JsObject, prop_name_si: u32, val: JsValue);
+
+    // Lookup / coercion
+    fn lookup_str(&self, val: JsValue) -> Option<String>;
+    fn coerce_primitive_bounded(&mut self, value: JsValue, prefer_string: bool) -> Result<JsValue, String>;
+    fn coerce_number_bounded(&mut self, value: JsValue) -> Result<f64, String>;
+
+    // Call infrastructure
+    fn call_function_sync(&mut self, callee: JsValue, receiver: JsValue, args: &[JsValue]) -> Result<JsValue, String>;
+
+    // Error handling
+    fn checked_object_ptr(&mut self, val: JsValue, error_msg: &str) -> Result<Option<*mut JsObject>, String>;
+    fn raise_type_error(&mut self, msg: &str) -> Result<(), String>;
+    fn error_message_text(&self, kind: &str, msg: &str) -> String;
+}
diff --git a/crates/oxide_vm/Cargo.toml b/crates/oxide_vm/Cargo.toml
index 9807b34d..700b1e43 100644
--- a/crates/oxide_vm/Cargo.toml
+++ b/crates/oxide_vm/Cargo.toml
@@ -9,6 +9,7 @@ description = "OxideJS - Register-based VM with epoch arena memory"
 [dependencies]
 oxide_bytecode = { path = "../oxide_bytecode" }
 oxide_kernel = { path = "../oxide_kernel" }
+oxide_runtime_api = { path = "../oxide_runtime_api" }
 oxide_types = { path = "../oxide_types" }
 bumpalo.workspace = true
 fast-float.workspace = true
diff --git a/crates/oxide_vm/src/builtins/array.rs b/crates/oxide_vm/src/builtins/array.rs
index b10051cb..44632516 100644
--- a/crates/oxide_vm/src/builtins/array.rs
+++ b/crates/oxide_vm/src/builtins/array.rs
@@ -3,8 +3,8 @@ use oxide_types::object::{JsObject, MAX_DENSE_PROPS};
 use oxide_types::value::JsValue;
 
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 macro_rules! array_ptr {
     ($vm:expr, $args:expr) => {{
diff --git a/crates/oxide_vm/src/builtins/array_buffer.rs b/crates/oxide_vm/src/builtins/array_buffer.rs
index 001dde2f..13059c43 100644
--- a/crates/oxide_vm/src/builtins/array_buffer.rs
+++ b/crates/oxide_vm/src/builtins/array_buffer.rs
@@ -3,8 +3,8 @@ use oxide_types::object::{JsObject, NativeFnPtr, PropAttributes};
 use oxide_types::value::JsValue;
 
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 pub(crate) const MAX_ARRAY_BUFFER_LENGTH: usize = 1 << 30;
 
diff --git a/crates/oxide_vm/src/builtins/boolean.rs b/crates/oxide_vm/src/builtins/boolean.rs
index 07adbf3f..41db5b94 100644
--- a/crates/oxide_vm/src/builtins/boolean.rs
+++ b/crates/oxide_vm/src/builtins/boolean.rs
@@ -1,8 +1,8 @@
 use oxide_types::object::JsObject;
 use oxide_types::value::JsValue;
 
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 pub fn boolean_constructor(vm: &mut Vm, args: &[u8]) -> NativeResult {
     let this_val = vm.reg(if args.is_empty() { 0 } else { args[0] });
diff --git a/crates/oxide_vm/src/builtins/data_view.rs b/crates/oxide_vm/src/builtins/data_view.rs
index b431c9f1..23481e63 100644
--- a/crates/oxide_vm/src/builtins/data_view.rs
+++ b/crates/oxide_vm/src/builtins/data_view.rs
@@ -4,8 +4,8 @@ use oxide_types::value::JsValue;
 
 use crate::builtins::array_buffer::array_buffer_data_ptr;
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 #[derive(Clone, Copy)]
 pub(crate) struct DataViewData {
diff --git a/crates/oxide_vm/src/builtins/date.rs b/crates/oxide_vm/src/builtins/date.rs
index 1436ff2d..7be0eacc 100644
--- a/crates/oxide_vm/src/builtins/date.rs
+++ b/crates/oxide_vm/src/builtins/date.rs
@@ -5,8 +5,8 @@ use oxide_types::object::JsObject;
 use oxide_types::value::JsValue;
 
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 fn get_timestamp(obj: &JsObject) -> f64 {
     let v = obj.get_prop_at(0);
diff --git a/crates/oxide_vm/src/builtins/error.rs b/crates/oxide_vm/src/builtins/error.rs
index 27024dd3..2cb12967 100644
--- a/crates/oxide_vm/src/builtins/error.rs
+++ b/crates/oxide_vm/src/builtins/error.rs
@@ -6,8 +6,8 @@ use oxide_types::object::JsObject;
 use oxide_types::value::JsValue;
 
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 fn create_error_object(vm: &mut Vm, error_proto_ptr: *mut JsObject, name: &str, message: &str) -> JsValue {
     let obj = vm
diff --git a/crates/oxide_vm/src/builtins/function.rs b/crates/oxide_vm/src/builtins/function.rs
index a69579d5..aa8d6ae9 100644
--- a/crates/oxide_vm/src/builtins/function.rs
+++ b/crates/oxide_vm/src/builtins/function.rs
@@ -2,8 +2,8 @@ use oxide_kernel::shape_forge::EMPTY_SHAPE_ID;
 use oxide_types::object::{JsObject, NativeFnPtr};
 use oxide_types::value::JsValue;
 
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 fn invoke_target(vm: &mut Vm, target_val: JsValue, this_val: JsValue, arg_regs: &[u8]) -> NativeResult {
     let args: Vec<JsValue> = arg_regs.iter().map(|&r| vm.reg(r)).collect();
diff --git a/crates/oxide_vm/src/builtins/global/annex_b.rs b/crates/oxide_vm/src/builtins/global/annex_b.rs
index 7e4950ab..dc7553c4 100644
--- a/crates/oxide_vm/src/builtins/global/annex_b.rs
+++ b/crates/oxide_vm/src/builtins/global/annex_b.rs
@@ -1,5 +1,5 @@
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 const ESCAPE_SAFE: &str = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789@*_+-./";
 
diff --git a/crates/oxide_vm/src/builtins/global/uri.rs b/crates/oxide_vm/src/builtins/global/uri.rs
index a37b7838..1c5344f8 100644
--- a/crates/oxide_vm/src/builtins/global/uri.rs
+++ b/crates/oxide_vm/src/builtins/global/uri.rs
@@ -1,5 +1,5 @@
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 const URI_UNESCAPED: &str = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_.!~*'()";
 const URI_RESERVED: &str = ";/?:@&=+$,#";
diff --git a/crates/oxide_vm/src/builtins/iterator.rs b/crates/oxide_vm/src/builtins/iterator.rs
index 4e561ef7..3f71ddc9 100644
--- a/crates/oxide_vm/src/builtins/iterator.rs
+++ b/crates/oxide_vm/src/builtins/iterator.rs
@@ -3,8 +3,8 @@ use oxide_types::object::JsObject;
 use oxide_types::value::JsValue;
 
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 const INNER_PROP: &str = "__inner__";
 const INDEX_PROP: &str = "__index__";
diff --git a/crates/oxide_vm/src/builtins/json.rs b/crates/oxide_vm/src/builtins/json.rs
index a0485c6e..3fda8733 100644
--- a/crates/oxide_vm/src/builtins/json.rs
+++ b/crates/oxide_vm/src/builtins/json.rs
@@ -6,8 +6,8 @@ use oxide_types::object::JsObject;
 use oxide_types::value::JsValue;
 
 use crate::builtins::object::walk_own_keys;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 pub fn json_parse(vm: &mut Vm, args: &[u8]) -> NativeResult {
     if args.len() < 2 {
diff --git a/crates/oxide_vm/src/builtins/map.rs b/crates/oxide_vm/src/builtins/map.rs
index b679350b..0f54d263 100644
--- a/crates/oxide_vm/src/builtins/map.rs
+++ b/crates/oxide_vm/src/builtins/map.rs
@@ -3,8 +3,8 @@ use oxide_types::object::JsObject;
 use oxide_types::value::JsValue;
 
 use crate::builtins::set::SetKey;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 macro_rules! native_try {
     ($expr:expr) => {
diff --git a/crates/oxide_vm/src/builtins/math.rs b/crates/oxide_vm/src/builtins/math.rs
index d1e3949b..c4b709f2 100644
--- a/crates/oxide_vm/src/builtins/math.rs
+++ b/crates/oxide_vm/src/builtins/math.rs
@@ -1,8 +1,8 @@
 use oxide_types::value::JsValue;
 
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 fn num(vm: &Vm, reg: u8) -> f64 {
     coercion::to_number(vm.reg(reg))
diff --git a/crates/oxide_vm/src/builtins/number.rs b/crates/oxide_vm/src/builtins/number.rs
index c6aa6760..0912c074 100644
--- a/crates/oxide_vm/src/builtins/number.rs
+++ b/crates/oxide_vm/src/builtins/number.rs
@@ -1,8 +1,8 @@
 use oxide_types::value::JsValue;
 
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 pub fn number_constructor(vm: &mut Vm, args: &[u8]) -> NativeResult {
     let n = if args.len() > 1 { coercion::to_number(vm.reg(args[1])) } else { 0.0 };
diff --git a/crates/oxide_vm/src/builtins/object.rs b/crates/oxide_vm/src/builtins/object.rs
index a2c5f2d0..aeaf671c 100644
--- a/crates/oxide_vm/src/builtins/object.rs
+++ b/crates/oxide_vm/src/builtins/object.rs
@@ -5,8 +5,8 @@ use oxide_types::private_key::is_private_name_key;
 use oxide_types::value::JsValue;
 
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 pub(crate) fn walk_own_keys(vm: &Vm, obj: &JsObject) -> Vec<(u32, u32)> {
     let mut keys: Vec<(u32, u32)> = Vec::new();
diff --git a/crates/oxide_vm/src/builtins/reflect.rs b/crates/oxide_vm/src/builtins/reflect.rs
index 10b123b7..c8fc1f9f 100644
--- a/crates/oxide_vm/src/builtins/reflect.rs
+++ b/crates/oxide_vm/src/builtins/reflect.rs
@@ -4,8 +4,8 @@ use oxide_types::value::JsValue;
 
 use crate::builtins::object::walk_own_keys;
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 pub fn reflect_apply(vm: &mut Vm, args: &[u8]) -> NativeResult {
     let target = arg(vm, args, 1);
diff --git a/crates/oxide_vm/src/builtins/regexp.rs b/crates/oxide_vm/src/builtins/regexp.rs
index f5293441..453b6389 100644
--- a/crates/oxide_vm/src/builtins/regexp.rs
+++ b/crates/oxide_vm/src/builtins/regexp.rs
@@ -3,8 +3,8 @@ use oxide_types::object::{JsObject, NativeFnPtr};
 use oxide_types::value::JsValue;
 
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 fn get_regexp_ptr(vm: &mut Vm, args: &[u8]) -> Result<*mut JsObject, JsValue> {
     let this_val = vm.reg(args[0]);
diff --git a/crates/oxide_vm/src/builtins/set.rs b/crates/oxide_vm/src/builtins/set.rs
index 05f8e3bd..c1862a88 100644
--- a/crates/oxide_vm/src/builtins/set.rs
+++ b/crates/oxide_vm/src/builtins/set.rs
@@ -4,8 +4,8 @@ use oxide_kernel::shape_forge::EMPTY_SHAPE_ID;
 use oxide_types::object::JsObject;
 use oxide_types::value::JsValue;
 
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 macro_rules! native_try {
     ($expr:expr) => {
diff --git a/crates/oxide_vm/src/builtins/string.rs b/crates/oxide_vm/src/builtins/string.rs
index dbc7fdfc..3b7782a9 100644
--- a/crates/oxide_vm/src/builtins/string.rs
+++ b/crates/oxide_vm/src/builtins/string.rs
@@ -3,9 +3,9 @@ use oxide_types::object::JsObject;
 use oxide_types::value::JsValue;
 
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
 use memchr::memchr;
+use oxide_runtime_api::NativeResult;
 
 fn this_string(vm: &Vm, args: &[u8]) -> String {
     coercion::to_string(vm.reg(args[0]))
diff --git a/crates/oxide_vm/src/builtins/stubs.rs b/crates/oxide_vm/src/builtins/stubs.rs
index 3769ae84..02307a8b 100644
--- a/crates/oxide_vm/src/builtins/stubs.rs
+++ b/crates/oxide_vm/src/builtins/stubs.rs
@@ -1,5 +1,5 @@
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 fn stub_error(vm: &mut Vm, name: &str) -> NativeResult {
     NativeResult::Err(crate::builtins::error::create_type_error(vm, &format!("{name} is not implemented")))
diff --git a/crates/oxide_vm/src/builtins/symbol.rs b/crates/oxide_vm/src/builtins/symbol.rs
index aedf0e67..266ba839 100644
--- a/crates/oxide_vm/src/builtins/symbol.rs
+++ b/crates/oxide_vm/src/builtins/symbol.rs
@@ -2,8 +2,8 @@ use oxide_types::object::JsObject;
 use oxide_types::value::JsValue;
 
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 pub fn symbol_constructor(vm: &mut Vm, args: &[u8]) -> NativeResult {
     let this_val = vm.reg(if args.is_empty() { 0 } else { args[0] });
diff --git a/crates/oxide_vm/src/builtins/typed_array.rs b/crates/oxide_vm/src/builtins/typed_array.rs
index 04b6f159..26d87792 100644
--- a/crates/oxide_vm/src/builtins/typed_array.rs
+++ b/crates/oxide_vm/src/builtins/typed_array.rs
@@ -4,8 +4,8 @@ use oxide_types::value::JsValue;
 
 use crate::builtins::array_buffer::{array_buffer_data_ptr, new_array_buffer, MAX_ARRAY_BUFFER_LENGTH};
 use crate::coercion;
-use crate::native::NativeResult;
 use crate::vm::Vm;
+use oxide_runtime_api::NativeResult;
 
 #[derive(Clone, Copy)]
 pub(crate) struct TypedArrayData {
diff --git a/crates/oxide_vm/src/dispatch/call.rs b/crates/oxide_vm/src/dispatch/call.rs
index b2729c01..76c918ad 100644
--- a/crates/oxide_vm/src/dispatch/call.rs
+++ b/crates/oxide_vm/src/dispatch/call.rs
@@ -1,6 +1,7 @@
-use crate::native::{NativeFn, NativeResult};
+use crate::native::NativeFn;
 use crate::vm::{native_fn_ptr_to_fn, FrameContinuation, Vm};
 use oxide_kernel::{builtins_debug, builtins_trace};
+use oxide_runtime_api::NativeResult;
 use oxide_types::object::JsObject;
 use oxide_types::value::JsValue;
 
diff --git a/crates/oxide_vm/src/native.rs b/crates/oxide_vm/src/native.rs
index c693b389..0a8ad198 100644
--- a/crates/oxide_vm/src/native.rs
+++ b/crates/oxide_vm/src/native.rs
@@ -1,38 +1,3 @@
-use oxide_types::value::JsValue;
-
-pub enum NativeResult {
-    Ok(JsValue),
-    Err(JsValue),
-    TailCall { callee: JsValue, this: JsValue, args: Vec<JsValue> },
-}
-
-impl NativeResult {
-    pub fn ok(val: JsValue) -> Self {
-        Self::Ok(val)
-    }
-
-    pub fn err(val: JsValue) -> Self {
-        Self::Err(val)
-    }
-
-    pub fn unwrap(self) -> JsValue {
-        match self {
-            Self::Ok(val) => val,
-            Self::Err(_) => panic!("called `NativeResult::unwrap()` on an `Err` value"),
-            Self::TailCall { .. } => panic!("called `NativeResult::unwrap()` on a `TailCall` value"),
-        }
-    }
-
-    pub fn map_err<E, F>(self, op: F) -> Result<JsValue, E>
-    where
-        F: FnOnce(JsValue) -> E,
-    {
-        match self {
-            Self::Ok(val) => Ok(val),
-            Self::Err(err) => Err(op(err)),
-            Self::TailCall { .. } => panic!("TailCall cannot be converted to Result"),
-        }
-    }
-}
+use oxide_runtime_api::NativeResult;
 
 pub type NativeFn = fn(&mut crate::vm::Vm, args: &[u8]) -> NativeResult;
diff --git a/crates/oxide_vm/src/session_gc.rs b/crates/oxide_vm/src/session_gc.rs
index a831b17c..e1169c9b 100644
--- a/crates/oxide_vm/src/session_gc.rs
+++ b/crates/oxide_vm/src/session_gc.rs
@@ -503,8 +503,8 @@ mod tests {
 
     use super::*;
     use crate::builtins::{array_buffer, data_view, map, set, typed_array};
-    use crate::native::NativeResult;
     use crate::vm::{CallFrame, FrameContinuation};
+    use oxide_runtime_api::NativeResult;
 
     fn plain_object(vm: &mut Vm) -> *mut JsObject {
         let proto_ptr = vm.session.builtin_world().object_proto.as_ptr() as *mut JsObject;
diff --git a/crates/oxide_vm/src/vm.rs b/crates/oxide_vm/src/vm.rs
index fb77a0cd..0b5f1039 100644
--- a/crates/oxide_vm/src/vm.rs
+++ b/crates/oxide_vm/src/vm.rs
@@ -9,10 +9,11 @@ use smallvec::SmallVec;
 
 pub use crate::bindings::init_kernel_builtins;
 use crate::coercion;
-use crate::native::{NativeFn, NativeResult};
+use crate::native::NativeFn;
 use crate::session_gc::SessionGc;
 use oxide_kernel::kernel::{KernelCore, KernelSession};
 use oxide_kernel::shape_forge::EMPTY_SHAPE_ID;
+use oxide_runtime_api::NativeResult;
 use oxide_types::error::{JsError, JsErrorKind};
 use oxide_types::mem::{Epoch, P};
 use oxide_types::object::{JsObject, JsString, NativeFnPtr};
@@ -785,11 +786,11 @@ impl Vm {
                     self.regs[2] = flags_val;
                     let func = unsafe { crate::vm::native_fn_ptr_to_fn(native_fn) };
                     let result = match func(self, &[0, 1, 2]) {
-                        crate::native::NativeResult::Ok(v) => v,
-                        crate::native::NativeResult::Err(e) => {
+                        oxide_runtime_api::NativeResult::Ok(v) => v,
+                        oxide_runtime_api::NativeResult::Err(e) => {
                             return Err(self.error_message_text("TypeError", &self.error_text(e)));
                         }
-                        crate::native::NativeResult::TailCall { .. } => {
+                        oxide_runtime_api::NativeResult::TailCall { .. } => {
                             return Err(self.error_message_text("TypeError", "unexpected tail call"));
                         }
                     };
@@ -1412,8 +1413,8 @@ impl Default for Vm {
 #[cfg(test)]
 mod tests {
     use super::{opcode, JsValue, TryHandler, Vm};
-    use crate::native::NativeResult;
     use oxide_bytecode::module::CompiledModule;
+    use oxide_runtime_api::NativeResult;
     use oxide_types::object::NativeFnPtr;
     use oxide_types::object::{JsObject, PropAttributes};
 
diff --git a/crates/oxide_vm/src/vm_dispatch_misc.rs b/crates/oxide_vm/src/vm_dispatch_misc.rs
index 45fdfa08..ceb1749d 100644
--- a/crates/oxide_vm/src/vm_dispatch_misc.rs
+++ b/crates/oxide_vm/src/vm_dispatch_misc.rs
@@ -1,7 +1,8 @@
 use std::sync::Arc;
 
-use crate::native::{NativeFn, NativeResult};
+use crate::native::NativeFn;
 use crate::vm::{native_fn_ptr_to_fn, CallFrame, ForInIter, FrameContinuation, Vm, MAX_PROTO_CHAIN_DEPTH};
+use oxide_runtime_api::NativeResult;
 use oxide_types::object::{JsObject, PropAttributes};
 use oxide_types::private_key::is_private_name_key;
 use oxide_types::value::JsValue;