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	8606
title	Comprehensive Testing for Fragments
state	Closed
labels	aitestingcore
assignees	tobiu
createdAt	Jan 13, 2026, 4:11 PM
updatedAt	Jan 13, 2026, 5:30 PM
githubUrl	https://github.com/neomjs/neo/issues/8606
author	tobiu
commentsCount	1
parentIssue	8601
subIssues	[]
subIssuesCompleted	0
subIssuesTotal	0
blockedBy	[]
blocking	[]
closedAt	Jan 13, 2026, 5:30 PM

Comprehensive Testing for Fragments

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

Closed v11.21.0 aitestingcore

tobiu commented on Jan 13, 2026, 4:11 PM

Part of Epic #8601.

Goal: Verify the functionality and stability of Neo.container.Fragment across different scenarios.

Tasks:

Unit Tests (VNode/Helper):
- Verify getPhysicalIndex correctly counts nested/sibling fragments.
- Verify createDeltas generates correct fragment-level deltas (not exploded children).
- Verify VNode structure creation.
E2E Tests (Playwright):
- Structure: Verify a Fragment renders as  ...children...  with NO wrapper element.
- Layout: Verify children of a Fragment participate in the parent's Grid/Flex layout as individual cells.
- Lifecycle:
  - Dynamically insert a Fragment.
  - Dynamically remove a Fragment.
  - Move a Fragment (e.g., reordering in a list).
- Nesting: Test Fragments inside Fragments.

tobiu added the ai label on Jan 13, 2026, 4:11 PM

tobiu added the testing label on Jan 13, 2026, 4:11 PM

tobiu added the core label on Jan 13, 2026, 4:11 PM

tobiu added parent issue #8601 on Jan 13, 2026, 4:11 PM

tobiu cross-referenced by #8601 on Jan 13, 2026, 4:17 PM

tobiu assigned to @tobiu on Jan 13, 2026, 4:18 PM

tobiu referenced in commit 894319e - "test: Comprehensive Testing for Fragments (#8606)" on Jan 13, 2026, 5:28 PM

tobiu Jan 13, 2026, 5:28 PM

Input from Gemini 3 Pro:

✦ I have implemented and passed comprehensive tests for Fragments.

Unit Tests: FragmentHelper.spec.mjs and FragmentHelperDomApi.spec.mjs verify index calculation, attribute skipping, and delta generation for both renderers.

E2E Tests: Fragment.spec.mjs verifies actual DOM structure (anchors, no wrapper) and correct layout participation in a browser environment using Playwright.

This completes the testing requirements.

tobiu closed this issue on Jan 13, 2026, 5:30 PM

tobiu cross-referenced by #8607 on Jan 13, 2026, 5:37 PM