diff --git a/src/browser/js/Caller.zig b/src/browser/js/Caller.zig
index 5f34a5b9..509adef0 100644
--- a/src/browser/js/Caller.zig
+++ b/src/browser/js/Caller.zig
@@ -60,6 +60,11 @@ fn initWithContext(self: *Caller, ctx: *Context, v8_context: *const v8.Context)
     ctx.local = &self.local;
 }
 
+pub fn initFromHandle(self: *Caller, handle: ?*const v8.FunctionCallbackInfo) void {
+    const isolate = v8.v8__FunctionCallbackInfo__GetIsolate(handle).?;
+    self.init(isolate);
+}
+
 pub fn deinit(self: *Caller) void {
     const ctx = self.local.ctx;
     const call_depth = ctx.call_depth - 1;
@@ -441,6 +446,11 @@ pub const FunctionCallbackInfo = struct {
         return .{ .local = local, .handle = v8.v8__FunctionCallbackInfo__INDEX(self.handle, @intCast(index)).? };
     }
 
+    pub fn getData(self: FunctionCallbackInfo) ?*anyopaque {
+        const data = v8.v8__FunctionCallbackInfo__Data(self.handle) orelse return null;
+        return v8.v8__External__Value(@ptrCast(data));
+    }
+
     pub fn getThis(self: FunctionCallbackInfo) *const v8.Object {
         return v8.v8__FunctionCallbackInfo__This(self.handle).?;
     }
diff --git a/src/browser/js/Context.zig b/src/browser/js/Context.zig
index 6b2e724a..ba160058 100644
--- a/src/browser/js/Context.zig
+++ b/src/browser/js/Context.zig
@@ -539,15 +539,6 @@ fn postCompileModule(self: *Context, mod: js.Module, url: [:0]const u8, local: *
     }
 }
 
-fn newFunctionWithData(local: *const js.Local, comptime callback: *const fn (?*const v8.FunctionCallbackInfo) callconv(.c) void, data: *anyopaque) js.Function {
-    const external = local.isolate.createExternal(data);
-    const handle = v8.v8__Function__New__DEFAULT2(local.handle, callback, @ptrCast(external)).?;
-    return .{
-        .local = local,
-        .handle = handle,
-    };
-}
-
 // == Callbacks ==
 // Callback from V8, asking us to load a module. The "specifier" is
 // the src of the module to load.
@@ -866,15 +857,14 @@ fn resolveDynamicModule(self: *Context, state: *DynamicModuleResolveState, modul
     // last value of the module. But, for module loading, we need to
     // resolve to the module's namespace.
 
-    const then_callback = newFunctionWithData(local, struct {
+    const then_callback = local.newFunctionWithData(struct {
         pub fn callback(callback_handle: ?*const v8.FunctionCallbackInfo) callconv(.c) void {
-            const isolate = v8.v8__FunctionCallbackInfo__GetIsolate(callback_handle).?;
             var c: Caller = undefined;
-            c.init(isolate);
+            c.initFromHandle(callback_handle);
             defer c.deinit();
 
-            const info_data = v8.v8__FunctionCallbackInfo__Data(callback_handle).?;
-            const s: *DynamicModuleResolveState = @ptrCast(@alignCast(v8.v8__External__Value(@ptrCast(info_data))));
+            const info = Caller.FunctionCallbackInfo{ .handle = callback_handle.? };
+            const s: *DynamicModuleResolveState = @ptrCast(@alignCast(info.getData() orelse return));
 
             if (s.context_id != c.local.ctx.id) {
                 // The microtask is tied to the isolate, not the context
@@ -891,19 +881,17 @@ fn resolveDynamicModule(self: *Context, state: *DynamicModuleResolveState, modul
         }
     }.callback, @ptrCast(state));
 
-    const catch_callback = newFunctionWithData(local, struct {
+    const catch_callback = local.newFunctionWithData(struct {
         pub fn callback(callback_handle: ?*const v8.FunctionCallbackInfo) callconv(.c) void {
-            const isolate = v8.v8__FunctionCallbackInfo__GetIsolate(callback_handle).?;
             var c: Caller = undefined;
-            c.init(isolate);
+            c.initFromHandle(callback_handle);
             defer c.deinit();
 
-            const info_data = v8.v8__FunctionCallbackInfo__Data(callback_handle).?;
-            const s: *DynamicModuleResolveState = @ptrCast(@alignCast(v8.v8__External__Value(@ptrCast(info_data))));
+            const info = Caller.FunctionCallbackInfo{ .handle = callback_handle.? };
+            const s: *DynamicModuleResolveState = @ptrCast(@alignCast(info.getData() orelse return));
 
             const l = &c.local;
-            const ctx = l.ctx;
-            if (s.context_id != ctx.id) {
+            if (s.context_id != l.ctx.id) {
                 return;
             }
 
diff --git a/src/browser/js/Local.zig b/src/browser/js/Local.zig
index 5ff6917d..65e577e9 100644
--- a/src/browser/js/Local.zig
+++ b/src/browser/js/Local.zig
@@ -82,6 +82,16 @@ pub fn createTypedArray(self: *const Local, comptime array_type: js.ArrayType, s
     return .init(self, size);
 }
 
+pub fn newFunctionWithData(
+    self: *const Local,
+    comptime callback: *const fn (?*const v8.FunctionCallbackInfo) callconv(.c) void,
+    data: *anyopaque,
+) js.Function {
+    const external = self.isolate.createExternal(data);
+    const handle = v8.v8__Function__New__DEFAULT2(self.handle, callback, @ptrCast(external)).?;
+    return .{ .local = self, .handle = handle };
+}
+
 pub fn runMacrotasks(self: *const Local) void {
     const env = self.ctx.env;
     env.pumpMessageLoop();
diff --git a/src/browser/webapi/streams/ReadableStream.zig b/src/browser/webapi/streams/ReadableStream.zig
index eba03a9e..a2033878 100644
--- a/src/browser/webapi/streams/ReadableStream.zig
+++ b/src/browser/webapi/streams/ReadableStream.zig
@@ -20,7 +20,6 @@ const std = @import("std");
 const log = @import("../../../log.zig");
 
 const js = @import("../../js/js.zig");
-const v8 = js.v8;
 const Page = @import("../../Page.zig");
 
 const ReadableStreamDefaultReader = @import("ReadableStreamDefaultReader.zig");
@@ -310,22 +309,21 @@ const PipeState = struct {
         const read_promise = try state.reader.read(state.page);
 
         // Create JS callback functions for .then() and .catch()
-        const then_fn = newFunctionWithData(local, &onReadFulfilled, state);
-        const catch_fn = newFunctionWithData(local, &onReadRejected, state);
+        const then_fn = local.newFunctionWithData(&onReadFulfilled, state);
+        const catch_fn = local.newFunctionWithData(&onReadRejected, state);
 
         _ = read_promise.thenAndCatch(then_fn, catch_fn) catch {
             state.finish(local);
         };
     }
 
-    fn onReadFulfilled(callback_handle: ?*const v8.FunctionCallbackInfo) callconv(.c) void {
-        const isolate = v8.v8__FunctionCallbackInfo__GetIsolate(callback_handle).?;
+    fn onReadFulfilled(callback_handle: ?*const js.v8.FunctionCallbackInfo) callconv(.c) void {
         var c: js.Caller = undefined;
-        c.init(isolate);
+        c.initFromHandle(callback_handle);
         defer c.deinit();
 
-        const info_data = v8.v8__FunctionCallbackInfo__Data(callback_handle).?;
-        const state: *PipeState = @ptrCast(@alignCast(v8.v8__External__Value(@ptrCast(info_data))));
+        const info = js.Caller.FunctionCallbackInfo{ .handle = callback_handle.? };
+        const state: *PipeState = @ptrCast(@alignCast(info.getData() orelse return));
 
         if (state.context_id != c.local.ctx.id) return;
 
@@ -333,10 +331,7 @@ const PipeState = struct {
         defer l.runMicrotasks();
 
         // Get the read result argument {done, value}
-        const result_val = js.Value{
-            .local = l,
-            .handle = v8.v8__FunctionCallbackInfo__INDEX(callback_handle, 0) orelse return,
-        };
+        const result_val = info.getArg(0, l);
 
         if (!result_val.isObject()) {
             state.finish(l);
@@ -374,14 +369,13 @@ const PipeState = struct {
         };
     }
 
-    fn onReadRejected(callback_handle: ?*const v8.FunctionCallbackInfo) callconv(.c) void {
-        const isolate = v8.v8__FunctionCallbackInfo__GetIsolate(callback_handle).?;
+    fn onReadRejected(callback_handle: ?*const js.v8.FunctionCallbackInfo) callconv(.c) void {
         var c: js.Caller = undefined;
-        c.init(isolate);
+        c.initFromHandle(callback_handle);
         defer c.deinit();
 
-        const info_data = v8.v8__FunctionCallbackInfo__Data(callback_handle).?;
-        const state: *PipeState = @ptrCast(@alignCast(v8.v8__External__Value(@ptrCast(info_data))));
+        const info = js.Caller.FunctionCallbackInfo{ .handle = callback_handle.? };
+        const state: *PipeState = @ptrCast(@alignCast(info.getData() orelse return));
 
         if (state.context_id != c.local.ctx.id) return;
 
@@ -404,19 +398,6 @@ const PipeState = struct {
             local.toLocal(r).resolve("pipe finished", {});
         }
     }
-
-    fn newFunctionWithData(
-        local: *const js.Local,
-        comptime callback: *const fn (?*const v8.FunctionCallbackInfo) callconv(.c) void,
-        data: *anyopaque,
-    ) js.Function {
-        const external = local.isolate.createExternal(data);
-        const handle = v8.v8__Function__New__DEFAULT2(local.handle, callback, @ptrCast(external)).?;
-        return .{
-            .local = local,
-            .handle = handle,
-        };
-    }
 };
 
 const Cancel = struct {