Coincide is a Mac app for coding agents, built natively without Electron

A Mac app, built the Mac way

As dev.to reported, a developer has published a short motion preview of Coincide, a Mac app for working with coding agents. These are AI programs that read, write and change software code for you. The app is meant for the agents the developer already uses, not for a new one of its own.

The pitch is in the architecture. Coincide's main interface is built with AppKit, Apple's long-standing toolkit for making Mac windows, menus and controls. Where it fits, such as the Settings screen, it also uses SwiftUI, Apple's newer toolkit. Both are written in Swift, Apple's programming language.

The maker's slogan is that it uses no Electron. Electron is a popular framework that builds desktop apps out of web technology. Many well-known apps use it, and some people prefer apps that use the Mac's own parts instead.

In practice, the source says this means native menus, standard Mac keyboard shortcuts, a native transcript of the conversation, and a picker for choosing the agent and model, all in one window.

Six agents, one conversation

Coincide lists six agents it can work with: Claude Code, Codex, Cursor, Grok Build, OpenCode and Antigravity. Each one runs through its own command-line tool, meaning the text-based program you would otherwise start from a terminal. Each also uses the login you already have for it.

That design has a practical consequence. The source says Coincide does not sell or meter tokens, the small units of text that AI providers usually charge for. Your usage and billing stay with the provider account behind each agent.

The model list follows the same logic. The source says the models available to you depend on which agents you have installed and which provider account you use. The preview shows the picker catalogs for Codex, Claude Code and Cursor, but your own list may look different.

How switching mid-thread works

The most interesting feature is changing agents in the middle of a conversation. When you do, the next agent is given a recap of the turns it missed. It then works in the same directory, meaning the same project folder on your computer.

Each agent keeps its own native session, which is its own running record of the work. If you switch back later, that agent resumes its session instead of starting over.

The author points to a separate deep-dive post for the mechanism and its limits. That is worth noting. A recap is a summary, not a full shared memory, so a second agent will know what happened only as well as the recap tells it. The source does not spell out those limits, so it is best not to assume a handoff is lossless.

What the demo does not show

The developer is unusually plain about the footage. The 10-second clip is an edited, illustrative demo. The conversation text was swapped for generic content for privacy, while the picker panels were captured from the real app. The motion design and synthesized sound are original.

The author also says it is not a fresh live handoff recording, and it does not show agents running at the same time. Likewise, the slogan describes how the Mac interface is built. It is not a benchmark, and it is not a claim that every task runs faster than in some other app.

• Real: the architecture and the picker panels.
• Staged: the conversation text.
• Not claimed: speed advantages or simultaneous agents.

That kind of labeling makes the announcement easier to judge. You can tell what has been shown and what has not.

Who might care, and what to check

This is for people who already use more than one coding agent and are tired of juggling windows. It is also for Mac users who care whether an app behaves like a Mac app. If you use none of the six agents, there is little here to try yet.

The source says the code is open under the MIT license, a permissive license that lets others read and reuse it. It links to a download, the source code and an original blog post. Anyone who wants to verify the claims, rather than take a demo clip on trust, can inspect the code.

The newsletter's quick-hits section pitched Coincide as a lightweight shell for agents developers already use, and that matches the source. Whether it feels better than the alternatives is something only hands-on use can settle.