diff --git a/src/interpreter/env.rs b/src/interpreter/env.rs
index 951b022..861b06e 100644
--- a/src/interpreter/env.rs
+++ b/src/interpreter/env.rs
@@ -78,12 +78,12 @@ pub type UserFunctionClosure = Box<UserFunctionInterface>;
 /// User-defined function execution interface
 pub trait UserFunctionInterface {
 	/// Handles the user function invocation
-	fn call(&mut self, context: CallerContext) -> Result<Option<RuntimeValue>, Error>; 
+	fn call(&mut self, module: &ModuleInstance, context: CallerContext) -> Result<Option<RuntimeValue>, Error>; 
 }
 
-impl<T> UserFunctionInterface for T where T: FnMut(CallerContext) -> Result<Option<RuntimeValue>, Error> {
-    fn call(&mut self, context: CallerContext) -> Result<Option<RuntimeValue>, Error> {
-        (&mut *self)(context)
+impl<T> UserFunctionInterface for T where T: FnMut(&ModuleInstance, CallerContext) -> Result<Option<RuntimeValue>, Error> {
+    fn call(&mut self, module: &ModuleInstance, context: CallerContext) -> Result<Option<RuntimeValue>, Error> {
+        (&mut *self)(module, context)
     }
 }
 
@@ -187,7 +187,7 @@ impl ModuleInstanceInterface for EnvModuleInstance {
 				// user-defined function
 				let user_index = idx - (INDEX_FUNC_MAX+1);
 				let func = self.user_functions.get(user_index as usize).ok_or(Error::Trap(format!("Trying to invoke user-defined function {}", user_index)))?;
-				func.borrow_mut().call(outer)
+				func.borrow_mut().call(&self.instance, outer)
 			},
 			// idx @ _ if idx == INDEX_FUNC_MAX + 1 => outer.value_stack.pop().map(|_| None), // TODO: `gas(i32) -> None` function
 			// idx @ _ if idx == INDEX_FUNC_MAX + 2 => Ok(Some(RuntimeValue::I32(0))), // TODO: `_storage_size() -> i32` function
diff --git a/src/interpreter/tests/basics.rs b/src/interpreter/tests/basics.rs
index 8fef569..f9d8e9a 100644
--- a/src/interpreter/tests/basics.rs
+++ b/src/interpreter/tests/basics.rs
@@ -122,7 +122,7 @@ fn global_get_set() {
 
 #[test]
 fn with_user_functions() {
-	use interpreter::{UserFunction, UserFunctions};
+	use interpreter::{UserFunction, UserFunctions, ModuleInstance};
 
 	let module = module()
 		.with_import(ImportEntry::new("env".into(), "custom_alloc".into(), External::Function(0)))
@@ -144,7 +144,7 @@ fn with_user_functions() {
 		UserFunction {
 			params: vec![ValueType::I32],
 			result: Some(ValueType::I32),
-			closure: Box::new(move |context: CallerContext| {
+			closure: Box::new(move |_module: &ModuleInstance, context: CallerContext| {
 				let prev = top;
 				top = top + context.value_stack.pop_as::<i32>()?;
 				Ok(Some(prev.into()))
@@ -158,7 +158,7 @@ fn with_user_functions() {
 		UserFunction {
 			params: vec![ValueType::I32],
 			result: Some(ValueType::I32),
-			closure: Box::new(move |_: CallerContext| {
+			closure: Box::new(move |_module: &ModuleInstance, _context: CallerContext|  {
 				rolling = rolling + 1;
 				Ok(Some(rolling.into()))
 			}),
@@ -180,14 +180,14 @@ fn with_user_functions() {
 
 #[test]
 fn with_user_functions_extended() {
-	use interpreter::{UserFunction, UserFunctions, UserFunctionInterface};
+	use interpreter::{UserFunction, UserFunctions, UserFunctionInterface, ModuleInstance};
 
 	struct UserMAlloc {
 		top: i32,
 	}
 
 	impl UserFunctionInterface for UserMAlloc {
-		fn call(&mut self, context: CallerContext) -> Result<Option<RuntimeValue>, Error> {
+		fn call(&mut self, _module: &ModuleInstance, context: CallerContext) -> Result<Option<RuntimeValue>, Error> {
 			let prev = self.top;
 			self.top += context.value_stack.pop_as::<i32>()?;
 			Ok(Some(prev.into()))