diff --git a/packages/extension-form/src/internal/Form.ts b/packages/extension-form/src/internal/Form.ts
index 209ac4f..ad621d8 100644
--- a/packages/extension-form/src/internal/Form.ts
+++ b/packages/extension-form/src/internal/Form.ts
@@ -1,6 +1,46 @@
-import type { Schema } from "effect"
+import { Schema, SubscriptionRef } from "effect"
 
 
 export interface Form<A, I, R> {
     readonly schema: Schema.Schema<A, I, R>
 }
+
+
+export type FormTree<S extends Schema.Schema<any>> = (
+    S extends Schema.Struct<any> ? StructFormField<S> :
+    S extends ScalarSchema ? ScalarFormField<S> :
+    S["Type"]
+)
+
+
+export interface FormField<S extends Schema.Schema<any>> {
+    readonly value: SubscriptionRef.SubscriptionRef<S["Type"]>
+}
+
+export interface ScalarFormField<S extends ScalarSchema> extends FormField<S> {
+    readonly _tag: "ScalarFormField"
+    readonly schema: S
+}
+
+export interface StructFormField<S extends Schema.Struct<any>> extends FormField<S> {
+    readonly _tag: "StructFormField"
+    readonly schema: S
+    readonly fields: { [K in keyof S["fields"]]: FormTree<S["fields"][K]> }
+}
+
+
+export type ScalarSchema = (
+    | Schema.String
+    | Schema.Number
+)
+
+
+const MySchema = Schema.Struct({
+    name: Schema.String,
+    values: Schema.Array(Schema.String),
+})
+
+type TestFormTree = FormTree<typeof MySchema>
+declare const testFormTree: TestFormTree
+
+testFormTree.fields.name.value