What is the 'Neural Link'?

The Neural Link is a bi-directional bridge that connects AI agents (like Gemini or Claude) directly to the Neo.mjs runtime. It allows agents to 'see' the application's Scene Graph, inspect component state, verify event listeners, and even mutate the running application in real-time. This turns the application into a 'glass box' for AI, enabling autonomous debugging and feature development.

Why is Neo.mjs called an 'Application Engine' instead of a framework?

Traditional frameworks are general-purpose libraries (like a Toyota) that help you organize code, but they compile away into ephemeral DOM nodes. Neo.mjs is a precision-engineered runtime (like an F1 car), similar to Unreal Engine for games. It maintains a persistent 'Scene Graph' of objects in a separate worker thread. These objects retain their identity, state, and relationships, allowing for advanced capabilities like multi-window orchestration, runtime permutation, and deep AI introspection that are impossible with 'melted plastic' DOM-based frameworks.

What is 'Context Engineering'?

Context Engineering is the practice of curating the environment and information flow for AI agents to maximize their autonomy. In Neo.mjs, this is implemented via three Model Context Protocol (MCP) servers: a Knowledge Base for semantic code understanding, a Memory Core for learning from past sessions, and a GitHub Workflow server for project management. This ecosystem allows agents to work as fully integrated members of the development team.

What is 'Object Permanence' in the context of Neo.mjs?

In Neo.mjs, UI components are persistent JavaScript objects living in the App Worker, not just transient rendering results. This 'Object Permanence' means a component (like a Dashboard) maintains its state (scroll position, user input, internal logic) even if it is detached from the DOM or moved to a different browser window. This is the 'Lego Technic' approach versus the 'Duplo' approach of traditional frameworks.

What is an 'Agent Operating System'?

Neo.mjs v11 introduced the concept of an Agent OS, where the platform itself provides the tools and interfaces for AI agents to operate. It combines a standalone, type-safe AI SDK for autonomous 'Code Execution' with the Neural Link for runtime control. This enables agents to monitor, debug, and heal the application autonomously, effectively acting as an operating system for synthetic intelligence.

How does Neo.mjs handle multi-window applications?

Neo.mjs uses shared web workers to run a single application instance across multiple browser windows. All windows share the same application state and data in real-time. Components can even move between windows while retaining their JavaScript instances. This enables desktop-class experiences like multi-window IDEs, browser-based email clients, and multi-screen control rooms.

What makes Neo.mjs different from React, Angular, or Vue?

Neo.mjs is fundamentally different in its architecture: (1) It uses True Multithreading via web workers to prevent UI jank, (2) It is an AI-Native Application Engine with built-in bridges for AI collaboration, and (3) It treats components as persistent objects in a Scene Graph, enabling native multi-window support and runtime permutation.

Frontmatter

id	8899
title	App-Worker Authority for VDOM IDs
state	Closed
labels	epicaiarchitecturecore
assignees	tobiu
createdAt	Jan 28, 2026, 4:29 PM
updatedAt	Jan 28, 2026, 6:41 PM
githubUrl	https://github.com/neomjs/neo/issues/8899
author	tobiu
commentsCount	2
parentIssue	null
subIssues	8900 Implement JIT ID Generation in TreeBuilder 8901 Remove Obsolete ID Sync Logic from VDom.mjs 8902 Verify VDOM ID Architecture Stability & Fix Tests 8903 Implement Scoped Deterministic IDs for Functional Components 8904 Verify Scoped Deterministic ID Generation for Functional Components
subIssuesCompleted	5
subIssuesTotal	5
blockedBy	[]
blocking	[]
closedAt	Jan 28, 2026, 6:41 PM

App-Worker Authority for VDOM IDs

Name: Neo.mjs Application Engine
Author: Neo.mjs

Closed v11.24.0 epicaiarchitecturecore

tobiu commented on Jan 28, 2026, 4:29 PM

Objective: Eliminate VDOM ID corruption and "Node Stealing" bugs (like #8898) by making the App Worker the sole authority for ID generation.

Context: Currently, VDOM IDs are often generated lazily in the VDOM Worker when initVnode or update logic runs. This creates a state mismatch where the App Worker's VDOM tree (the blueprint) lacks IDs that the VDOM Worker's VNode tree (the DOM representation) has. We rely on complex, brittle heuristics in syncVnodeTree to retroactively map these IDs back. This logic fails during disjoint updates or structural shifts (like Grid recycling), leading to corruption.

Strategy: Shift ID generation to the App Worker before the VDOM payload is sent.

Authority: TreeBuilder (App Worker) assigns immutable IDs to any VDOM node that lacks them during the build phase.
Persistence: These IDs are assigned in-place to the VDOM object, ensuring they persist for the lifetime of the component.
Strictness: The VDOM Worker (VNode.mjs) will now throw an error if it receives a node without an ID, enforcing the new contract.
Simplification: The brittle ID syncing logic in VDom.mjs and VdomLifecycle.mjs becomes obsolete and will be removed.

Implementation Plan:

Ticket 1: Implement JIT ID Generation in TreeBuilder.mjs (App Authority).
Ticket 2: Remove obsolete ID Sync logic from VDom.mjs and VdomLifecycle.mjs.
Ticket 3: Verify Stability and fix regressions in Test Suite.

Impact:

Deterministic State: No more "guessing" which node is which.
Performance: Slight O(n) cost in App Worker offset by removal of O(n) syncing cost.
Robustness: Eliminates an entire class of synchronization bugs.

tobiu added the epic label on Jan 28, 2026, 4:29 PM

tobiu added the ai label on Jan 28, 2026, 4:29 PM

tobiu added the architecture label on Jan 28, 2026, 4:29 PM

tobiu added the core label on Jan 28, 2026, 4:29 PM

tobiu added sub-issue #8900 on Jan 28, 2026, 4:34 PM

tobiu added sub-issue #8901 on Jan 28, 2026, 4:34 PM

tobiu added sub-issue #8902 on Jan 28, 2026, 4:34 PM

tobiu assigned to @tobiu on Jan 28, 2026, 5:41 PM

tobiu added sub-issue #8903 on Jan 28, 2026, 6:09 PM

tobiu added sub-issue #8904 on Jan 28, 2026, 6:19 PM

tobiu Jan 28, 2026, 6:40 PM

Input from Gemini 3 Pro:

✦ # Architecture Shift Complete: App-Worker Authority for VDOM IDs

This Epic marks a significant milestone in the Neo.mjs rendering engine architecture. We have successfully transitioned VDOM ID generation from a reactive, worker-dependent model to a proactive, App-Authority model.

The Core Shift

Before (Worker-First)

Mechanism: The App Worker often sent VDOM nodes without IDs. The VDOM Worker (or Helper) would lazily generate IDs (neo-vnode-X) upon receipt.

The Flaw: This created a split-brain state where the App Worker's blueprint (vdom) did not match the VDOM Worker's reality (vnode). We relied on complex, brittle heuristics (syncVnodeTree) to "guess" which new App node corresponded to which old Worker node to sync IDs back. This logic fundamentally failed during disjoint updates or structural shifts (like Grid recycling), leading to "Node Stealing" (ID corruption).

After (App-First)

Mechanism: The App Worker (TreeBuilder) acts as the Sole Authority. It ensures every node has an immutable ID before the payload leaves the thread.

The Fix: Since the App Worker dictates identity, there is no ambiguity. The VDOM Worker simply accepts the IDs provided. We no longer need to "sync back" IDs, eliminating an entire class of synchronization bugs. src/vdom/VNode.mjs now strictly enforces this by throwing an error if it receives a node without an ID (in production).

Functional Component Innovation: "Scoped Deterministic IDs"

A major challenge was adapting this "stateful" architecture to Functional Components, which are inherently stateless (generating fresh VDOM objects on every render).

The Solution: We implemented Scoped Deterministic ID Generation in Neo.functional.component.Base.

Logic: Instead of random IDs, we generate IDs based on the component's structure: componentId__scope__index.

Shielding: Developers can "shield" sub-trees from index shifts by assigning a custom id to a container. This starts a new ID scope (prefix), ensuring that inserting a node before the container does not cascade ID changes into the container's children.

Result: Functional components now enjoy stable, persistent identity across re-renders without needing to read from the VDOM Worker's state. This enables efficient, granular DOM updates even for stateless views.

Verification & Stability

Unit Tests: The entire VDOM unit test suite (256 tests) has been stabilized and updated to enforce the new strict ID contract.

New Coverage: Dedicated test suites (test/playwright/unit/functional/IdGeneration.spec.mjs and test/playwright/unit/component/IdGeneration.spec.mjs) explicitly verify the stability and persistence of the new ID generation strategies.

Outcome: The rendering engine is now more deterministic, robust, and easier to debug. "Node Stealing" is structurally impossible under the new model.

tobiu Jan 28, 2026, 6:40 PM

tobiu closed this issue on Jan 28, 2026, 6:41 PM