diff --git a/packages/common/src/traits/Identifiable.trait.ts b/packages/common/src/traits/Identifiable.trait.ts
index 34fc704..ff7aeac 100644
--- a/packages/common/src/traits/Identifiable.trait.ts
+++ b/packages/common/src/traits/Identifiable.trait.ts
@@ -19,7 +19,7 @@ export module Identifiable {
     ): boolean {
         // Two elements can only be equal if they both have a defined ID
         return Option.isSome(that.id) && Option.isSome(to.id)
-            ? Equal.equals(that.id, to.id)
+            ? Equal.equals(that.id.value, to.id.value)
             : false
     }
 }
diff --git a/packages/server/src/TodoRepository.ts b/packages/server/src/TodoRepository.ts
index c532ac3..3411103 100644
--- a/packages/server/src/TodoRepository.ts
+++ b/packages/server/src/TodoRepository.ts
@@ -6,24 +6,33 @@ export class TodoRepository extends Context.Tag("TodoRepository")<TodoRepository
 
 export class TodoRepositoryService {
     constructor(
-        readonly ref: SubscriptionRef.SubscriptionRef<Todo[]>
+        readonly ref: SubscriptionRef.SubscriptionRef<(Todo & { id: Option.Some<string> })[]>
     ) {}
 
     get(id: string) {
         return this.ref.get.pipe(
-            Effect.map(Array.findFirst(todo => todo.id === id))
+            Effect.map(Array.findFirst(todo => todo.id.value === id))
         )
     }
     getIndex(id: string) {
         return this.ref.get.pipe(
-            Effect.map(Array.findFirstIndex(todo => todo.id === id))
+            Effect.map(Array.findFirstIndex(todo => todo.id.value === id))
         )
     }
 
-    update(todo: Todo) {
-        return Effect.gen(this, function*() {
-            const todoWithSameIDIndex = yield* this.getIndex(todo.id)
+    add(todo: Todo & { id: Option.None<string> }) {
+        return Ref.update(this.ref, todos =>
+            Array.append(todos, new Todo({
+                ...todo,
+                id: Option.some(""),
+            }))
+        )
+    }
 
+    update(todo: Todo & { id: Option.Some<string> }) {
+        return Effect.gen(this, function*() {
+            const index = yield* yield* this.getIndex(todo.id.value)
+            yield* Ref.update(this.ref, Array.replace(index, todo))
         })
     }
 }
@@ -33,7 +42,7 @@ export const createDefaultTodos = TodoRepository.pipe(Effect.flatMap(repo =>
     Ref.update(repo, todos =>
         Array.appendAll(todos, [
             new Todo({
-                id: "1",
+                id: Option.some("1"),
                 title: "A test todo",
                 content: "Lorem ipsum",
                 due: Option.none(),