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	8827
title	test: Comprehensive Verification of Asymmetric VDOM Merging and Callbacks
state	Closed
labels	testingcore
assignees	tobiu
createdAt	Jan 20, 2026, 12:30 PM
updatedAt	Jan 20, 2026, 6:09 PM
githubUrl	https://github.com/neomjs/neo/issues/8827
author	tobiu
commentsCount	1
parentIssue	null
subIssues	[]
subIssuesCompleted	0
subIssuesTotal	0
blockedBy	[]
blocking	[]
closedAt	Jan 20, 2026, 6:09 PM

test: Comprehensive Verification of Asymmetric VDOM Merging and Callbacks

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

Closed v11.23.0 testingcore

tobiu commented on Jan 20, 2026, 12:30 PM

This task aims to rigorously stress-test the new Scoped + Aggregated VDOM engine (v11) to ensure precision, efficiency, and correctness of the new merging logic (canMergeUpdate) and its integration with the promise/callback system.

Objectives:

Verify Selective Merging: Ensure that when a parent updates, it only aggregates dirty children, leaving clean children pruned/untouched.
Verify Callback Execution: Ensure that promises returned by child.promiseUpdate() are correctly resolved when the child is merged into a parent's update cycle.
Verify State Management: Ensure needsVdomUpdate is correctly reset for merged children.

Key Test Scenarios:

Selective Merging (The Toolbar Case):
- Setup: Container with 3 Buttons.
- Action: Dirty Button 1 and 3. Keep Button 2 clean. Trigger Parent update.
- Expectation: Update bundle includes Parent, Btn1, Btn3. Excludes Btn2.
Promise/Callback Signal Chain:
- Setup: Child component waiting on promiseUpdate().
- Action: Merge Child into Parent update.
- Expectation: Child's promise resolves when Parent finishes. Verify callback data and timing.
Nested Merging (Transitive chains):
- Setup: Parent -> Child (Container) -> Grandchild.
- Action: Dirty all three.
- Expectation: Grandchild merges to Child, Child merges to Parent. Parent delta contains all.

Implementation:

Create test/playwright/unit/vdom/AsymmetricMerging.spec.mjs.
Use explicit tracking arrays to verify callback firing order.

tobiu added the testing label on Jan 20, 2026, 12:30 PM

tobiu added the core label on Jan 20, 2026, 12:30 PM

tobiu assigned to @tobiu on Jan 20, 2026, 12:30 PM

tobiu referenced in commit 954791b - "test: Add Comprehensive Asymmetric VDOM Merging Verification (#8827) & docs" on Jan 20, 2026, 6:08 PM

tobiu Jan 20, 2026, 6:08 PM

Input from Gemini 3 Pro:

✦ I have completed the verification of the Asymmetric VDOM Merging logic.

Implementation:

Created test/playwright/unit/vdom/AsymmetricMerging.spec.mjs.

Implemented robust test patterns using testRun counters for unique IDs and setSilent + promiseUpdate for state mutation.

Verified Scenarios:

Selective Merging: Confirmed that parent updates only aggregate dirty children (e.g., Toolbar case).

Promise/Callback Chain: Confirmed that child.promiseUpdate() resolves correctly when merged into a parent update.

Nested Merging: Confirmed correct bundling of Grandchild -> Child -> Parent updates.

Custom Config Hooks: Confirmed that callbacks in custom config setters are executed even when merged.

Leapfrog Merging: Validated that a Grandchild can merge into a Grandparent even if the intermediate Parent is clean/skipped.

Structural Merging: Validated that adding a child (container.add) merges correctly into a pending parent update.

Documentation:

Enhanced src/manager/VDomUpdate.mjs and src/mixin/VdomLifecycle.mjs with intent-driven JSDoc explaining the merging strategies, optimization goals, and leapfrog capabilities.

All tests passed successfully. The VDOM merging engine is robust and well-documented.

tobiu closed this issue on Jan 20, 2026, 6:09 PM

tobiu referenced in commit fc9bc36 - "fix: Resolve ntype conflict in AsymmetricMerging tests (#8827)" on Jan 20, 2026, 6:13 PM