Whiteboard is a Developer tools tool: Open-source desktop canvas for reviewing coding agent work.

How much does Whiteboard cost?

Whiteboard is Open source; there is no mandatory paid plan.

What are the best alternatives to Whiteboard?

Community-listed alternatives to Whiteboard include Flagsmith, Insomnia, Omnara, Tessary.

What does Whiteboard integrate with?

Whiteboard integrates with Claude Code, Codex, Cursor, OpenCode, GitHub Copilot CLI, Homebrew and more.

Which platforms does Whiteboard support?

Whiteboard is available on macos, windows, linux.

Whiteboard

Open-source desktop canvas for reviewing coding agent work

Open sourceDeveloper tools

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Whiteboard is a developer tools tool for Developers and Enterprise, offered as open source. Popular alternatives include Flagsmith, Insomnia, Omnara.

About Whiteboard

Whiteboard is an open-source desktop app from /dev/fast, a startup that says it is backed by Y Combinator. It gives developers and their coding agents a shared canvas for reviewing changes: the agent explains a diff, draws sequence and database diagrams, and links each step back to the source, so you review architecture and decisions instead of scrolling raw lines.

At its core is a semantic diff viewer built on an AST-based Rust library that summarises long new functions as pseudocode, always shows signatures and collapses test and docs changes, with a WASM plugin system. A decision log lets agents link their traces so reviewers see what was decided autonomously. It bundles a Code OSS editor for VS Code keybindings and LSP, sets up Claude Code, Codex, Cursor, OpenCode and Copilot CLI through MCP, and can run its review server on a remote Linux host over SSH. The app is free under MIT; a hosted team version is planned.

It fits engineers reviewing large agent-written pull requests. GitHub pull requests remain the default for line comments and approvals, and Cursor is an AI editor where you write code. Whiteboard is beta: you cannot edit files in it, multi-repo reviews are weak and shared reviews do not update.

Whiteboard launched on Product Hunt on October 22, 2026 and finished #14 of the day; its GitHub repository has about 3,300 stars. Buying tip: it costs nothing, so try it on one large PR with the agent you already use before changing your review process.

Key features of Whiteboard

Agent-drawn sequence and entity relationship diagrams linked to code
AST-aware semantic diff viewer written in Rust
Pseudocode summaries of long functions and collapsed test changes
Decision log of agent traces for auditing autonomous choices
Code OSS base with VS Code keybindings and LSP support
Automatic MCP setup for Claude Code, Codex, Cursor and OpenCode
Experimental remote review server on a Linux host over SSH
WASM-based plugin system for custom diff handling

Pros and cons

Pros

Free and MIT-licensed, runs against local checkouts
Works with the coding agents teams already use
Reviews structure and decisions, not only changed lines
Native builds for macOS, Windows and Linux
Telemetry excludes code, diffs and prompts and can be turned off

Cons

Beta software; files cannot be edited inside the app
Reviews spanning several repositories are poorly supported
Shared reviews do not update and must be re-shared
Hosted team version is not available yet
Linux packages target x86-64 Fedora, Ubuntu and Arch only

Whiteboard pricing

Whiteboard uses a open source model.

Plan	Price	Includes
Open source	$0	MIT-licensed desktop app for macOS, Windows and Linux

Source: github.com · checked on Oct 25, 2026

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How Whiteboard compares in Developer tools

Rank by votes: #2 / 57
Starting price: $0
Free alternatives: 12

Whiteboard ranks #2 of 57 developer tools tools by community votes and is not directly comparable on price.

Common use cases

1Reviewing large pull requests written by Claude Code or Codex
2Checking an agent's design decisions before merging
3Explaining a change to teammates with generated diagrams
4Auditing database schema changes through ER diagrams
5Iterating on prototypes with an agent on a shared canvas

Best for

Developers who let coding agents write large changes and want a visual, architecture-level way to review them.

Not ideal for

Teams that need an editor or a full review workflow with approvals and comments (GitHub, Cursor).

Integrations

Claude Code
Codex
Cursor
OpenCode
GitHub Copilot CLI
Homebrew

Our take

Whiteboard is worth installing if agent-written PRs have outgrown line-by-line review, since diagrams and semantic diffs make intent easier to check. Use it alongside GitHub reviews rather than instead of them while it is in beta.

FAQ

What is Whiteboard?: Whiteboard is a Developer tools tool: Open-source desktop canvas for reviewing coding agent work.
How much does Whiteboard cost?: Whiteboard is Open source; there is no mandatory paid plan.
What are the best alternatives to Whiteboard?: Community-listed alternatives to Whiteboard include Flagsmith, Insomnia, Omnara, Tessary.
What does Whiteboard integrate with?: Whiteboard integrates with Claude Code, Codex, Cursor, OpenCode, GitHub Copilot CLI, Homebrew and more.
Which platforms does Whiteboard support?: Whiteboard is available on macos, windows, linux.
Who is Whiteboard for?: Developers who let coding agents write large changes and want a visual, architecture-level way to review them.

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