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	9548
title	`calcValueBands` broken state initialization on `splice` (StoreValueBanding test failure)
state	Closed
labels	bugaitesting
assignees	tobiu
createdAt	Mar 25, 2026, 12:06 PM
updatedAt	Mar 25, 2026, 12:09 PM
githubUrl	https://github.com/neomjs/neo/issues/9548
author	tobiu
commentsCount	1
parentIssue	null
subIssues	[]
subIssuesCompleted	0
subIssuesTotal	0
blockedBy	[]
blocking	[]
closedAt	Mar 25, 2026, 12:09 PM

`calcValueBands` broken state initialization on `splice` (StoreValueBanding test failure)

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

Closed v12.1.0 bugaitesting

tobiu commented on Mar 25, 2026, 12:06 PM

Description

A test failure occurred in test/playwright/unit/data/StoreValueBanding.spec.mjs regarding calcValueBands with records.

The underlying root cause was identified in src/collection/Base.mjs. In the splice method, calcValueBands was being called with index:

me.calcValueBands(index);

Since index can be null (e.g. when appending to a store), the calcValueBands(startIndex=0) method head parsed null as the value instead of falling back to the default 0. This resulted in startIndex being null, skipping the startIndex === 0 map clear, and keeping broken state in the map for value banding.

Fix

This was fixed by modifying the call inside splice to fallback to 0 if index is falsy (index || 0):

me.calcValueBands(index || 0);

The unit test StoreValueBanding.spec.mjs now passes correctly.

tobiu added the bug label on Mar 25, 2026, 12:06 PM

tobiu added the ai label on Mar 25, 2026, 12:06 PM

tobiu added the testing label on Mar 25, 2026, 12:06 PM

tobiu referenced in commit ce551a7 - "fix: resolve calcValueBands state initialization bug on splice (#9548)" on Mar 25, 2026, 12:08 PM

tobiu assigned to @tobiu on Mar 25, 2026, 12:08 PM

tobiu Mar 25, 2026, 12:09 PM

Input from Gemini 3.1 Pro:

✦ The issue was caused by calcValueBands receiving null as the startIndex parameter when called from splice(index). The method head calcValueBands(startIndex=0) only applies the default when the parameter is strictly undefined, not null. This resulted in skipping the startIndex === 0 cache clear and breaking the map state.

This has been resolved by defaulting to 0 when calling the method from splice: me.calcValueBands(index || 0);

The change has been pushed to the repository and the unit test is now passing.

tobiu closed this issue on Mar 25, 2026, 12:09 PM

calcValueBands broken state initialization on splice (StoreValueBanding test failure)

Description

Fix

`calcValueBands` broken state initialization on `splice` (StoreValueBanding test failure)