Key takeaways
- Official successor to Crystal (3,000+ stars, deprecated February 2026) — Stravu describes it as 'the direct successor — same idea, more tools,' with no migration step since both wrap the same Claude Code CLI
- Visual-first workspace: sessions live on a kanban board that auto-moves cards between In Progress, Waiting, and Review, plus WYSIWYG editors for markdown, mockups, Mermaid diagrams, and data models with red/green diffs
- Free core for individual users with no feature limits; MIT-licensed since April 30, 2026, after launching as a closed-source free download in late 2025
FAQ
What is Nimbalyst?
Nimbalyst is an open-source visual workspace for working with AI coding agents — it manages parallel Claude Code and Codex sessions on a kanban board, with git worktree isolation, WYSIWYG editors, task tracking, and an iOS companion app.
How much does Nimbalyst cost?
The core Nimbalyst experience is completely free for individual users with no feature limits or trial period. Pricing beyond the free individual tier is not publicly listed as of June 2026.
What AI agents does Nimbalyst support?
Claude Code (Anthropic) and Codex (OpenAI) as primary engines, with OpenCode, GitHub Copilot, and Codex-via-ACP support in alpha.
How is Nimbalyst different from Crystal?
Nimbalyst is Crystal's official successor from the same maker (Stravu) — it keeps Crystal's parallel-session and git-worktree model and adds a session kanban, visual WYSIWYG editors, task tracking, an extension system, and a native iOS app.
Executive Summary
Nimbalyst is an open-source visual workspace for building with AI coding agents — Stravu's official successor to Crystal, the multi-session Claude Code app it deprecated in February 2026 with the note "we recommend migrating to Nimbalyst, our successor product."[1] Where Crystal focused on running parallel agent sessions in git worktrees, Nimbalyst keeps that foundation and bets that "visual interfaces are the highest bandwidth" way to work with agents: sessions are managed on a kanban board, and plans, mockups, diagrams, and data models are edited WYSIWYG with red/green diffs instead of raw text.[2][3]
The product launched as a free closed-source download in late 2025, then was MIT open-sourced on April 30, 2026.[4][5] As of June 2026 the repo holds 795 stars and 110 forks, with the latest release (v0.65.0) shipped June 9, 2026 — ten releases in the ten days prior.[6][7] The core experience is completely free for individual users with no feature limits.[2]
| Attribute | Value |
|---|---|
| Company | Stravu (maker of Crystal) |
| Founded | 2025 (Stravu); Nimbalyst repo created October 30, 2025[6] |
| Funding | Not publicly disclosed |
| GitHub Stars | 795 (as of June 11, 2026; open-sourced April 30, 2026)[6] |
| License | MIT |
Product Overview
Nimbalyst positions itself as "the open-source visual workspace for building with Codex, Claude Code, and more."[2] Rather than a terminal wrapper, it is a local desktop app where agent sessions, project context, and tasks live in one place: each agent session is a card on a kanban board that moves automatically between columns — In Progress when the agent runs, Waiting when it asks a question, Review when it finishes — and Claude Code and Codex sessions are treated identically.[2] Stravu calls it "the direct successor — same idea, more tools" to Crystal, using the same Claude Code CLI under the hood with no migration step.[3]
The visual layer is the differentiator: first-class WYSIWYG editors for markdown, UI mockups, Mermaid diagrams, Excalidraw drawings, CSVs, and data models, all with inline red/green diff review so agent edits to a plan or mockup are reviewed rendered, not as plaintext.[6][8]
Key Capabilities
| Capability | Description |
|---|---|
| Session Kanban | Parallel agent sessions as cards that auto-advance through In Progress / Waiting / Review; search and resume |
| Multi-Agent Engines | Claude Code and Codex first-class; OpenCode, Copilot, and Codex-via-ACP in alpha[2] |
| WYSIWYG Editors | Markdown, mockups, Mermaid, Excalidraw, CSV, data models, and code — with rendered red/green diffs |
| Git Worktrees | Isolated worktrees per session, AI-powered commits, embedded terminal |
| Task Tracking | Built-in tasks agents can execute against — "Linear for coding agents" in Stravu's framing[5] |
| Mobile Dashboard | Native iOS app to monitor agents and approve changes via visual diffs |
| Extensions | Extensible editor system for custom file types[6] |
Product Surfaces
| Surface | Description | Availability |
|---|---|---|
| macOS App | DMG for Apple Silicon and Intel | GA |
| Windows App | EXE installer, Windows 10+ | GA |
| Linux App | AppImage | GA |
| iOS App | Native SwiftUI companion on the App Store | GA |
Technical Architecture
Nimbalyst is an Electron desktop application written in TypeScript, built on React, Meta's Lexical editor framework, Monaco, and Excalidraw; the iOS companion is native SwiftUI.[6] Like Crystal before it, it orchestrates agent CLIs locally — creating a git worktree per session, launching the chosen agent, and tracking every file change for rendered diff review.[3]
Key Technical Details
| Aspect | Detail |
|---|---|
| Deployment | Local desktop app (macOS/Windows/Linux) + native iOS companion |
| Model(s) | Claude Code (Anthropic), Codex (OpenAI); OpenCode and Copilot in alpha |
| Integrations | Git worktrees, embedded terminal, GitHub Copilot (alpha), ACP |
| Open Source | Yes — MIT License (since April 30, 2026)[6][5] |
Strengths
- Official Crystal lineage — Inherits a proven parallel-session, git-worktree model and a migrating community from a 3,000-star predecessor; Stravu directs all Crystal users here, with no migration step[1][3]
- Visual diff review beyond code — Rendered red/green diffs on markdown, mockups, and diagrams is rare among agent managers; HN users called out seeing "changes in rendered markdown instead of having to view them plaintext"[9]
- Engine-agnostic kanban — Claude Code and Codex sessions are identical cards with the same phases and metadata, making cross-engine comparison workflows natural[2]
- Broadest platform spread in the category — macOS, Windows, and Linux desktop builds plus a native iOS app for monitoring and approving agent work remotely[2]
- Rapid release cadence — v0.65.0 shipped June 9, 2026, the tenth release since May 31; the repo is pushed to near-daily[7][6]
- Free with no feature limits for individuals — MIT-licensed with a core experience that is "completely free for individual users with no feature limits or trial period"[2]
Cautions
- Modest independent traction so far — 795 stars as of June 2026, versus 3,080 for deprecated Crystal and 21,000+ for cmux; the code has only been open since April 30, 2026[6][5]
- Closed-source history — Launched as a closed-source free download; an early HN commenter flagged that the repo held "screenshots... but no code." Stravu reversed course in April 2026, but the open-source commitment is young[4]
- Electron footprint — Heavier than native-Swift rivals like cmux; worktree-per-session also costs disk space on large repos
- Issue backlog — 233 open issues against a small team, as of June 2026[6]
- Agent dependency — Requires Claude Code or Codex to be installed and authenticated separately; agent subscription/API costs are yours
- Unclear monetization — "Free for individual users" implies future paid tiers, but no team/enterprise pricing is published, leaving the business model unproven
What Developers Say
Community discussion is thin but real — Nimbalyst's largest independent thread is a 29-point Hacker News post from December 2025, plus a Show HN for the April 2026 open-sourcing:[9][5]
"I like that I can see the changes in rendered markdown instead of having to view them plaintext." — an HN commenter, December 2025[9]
"Really cool! Switched out my default terminal to this and am using it for the last half an hour." — an HN commenter, December 2025[9]
"Heads up - there are a couple of screenshots in this repo, but no code. This is not an open source project. Cool idea, though." — an HN commenter, November 2025 (pre-dating the April 2026 open-sourcing)[4]
"Congrats on going open-source, can't wait to see the community contributions come in." — an HN commenter, April 2026[5]
As of June 11, 2026 there is no large HN front-page thread or substantive Reddit discussion of Nimbalyst — coverage is mostly Stravu's own content plus third-party write-ups like SitePoint's.[8] For a product whose predecessor had a real community, that limited independent signal is itself a data point.
Pricing & Licensing
| Tier | Price | Includes |
|---|---|---|
| Individual | Free | Core experience with "no feature limits or trial period"[2] |
| Team / Enterprise | Not publicly listed | Not announced as of June 2026 |
Licensing model: MIT License for the desktop and iOS apps, open-sourced April 30, 2026.[6][5]
Hidden costs: Users pay for their own Claude Code or Codex subscriptions/API usage. The "free for individual users" phrasing leaves room for future paid team tiers.
Competitive Positioning
Direct Competitors
| Competitor | Differentiation |
|---|---|
| Crystal | Nimbalyst's deprecated predecessor from the same maker — Nimbalyst includes every Crystal feature plus kanban, visual editors, and iOS[3] |
| Conductor | Conductor is a polished commercial Mac app; Nimbalyst is MIT-licensed, cross-platform, and free for individuals |
| cmux | cmux is a native terminal layer (no orchestration); Nimbalyst is a full visual orchestrator with worktrees, kanban, and editors |
| Vibe Kanban | Both put agent sessions on a kanban board; Nimbalyst adds WYSIWYG document/mockup editing and a native iOS app |
When to Choose Nimbalyst Over Alternatives
- Choose Nimbalyst when: You want free, open-source multi-agent orchestration with visual diff review of plans and mockups — or you're a Crystal user, since Stravu itself directs you here[1]
- Choose Conductor when: You want a commercial product with support and Mac-native polish
- Choose cmux when: You want a fast native terminal with notification awareness and no imposed workflow
- Choose Vibe Kanban when: You want kanban-style session management without the document/mockup editing layer
Ideal Customer Profile
Best fit:
- Crystal users migrating to the maintained successor — same worktree model, no migration step
- Developers who iterate with agents on specs, mockups, and diagrams and want rendered (not plaintext) diff review
- Individuals wanting a free, MIT-licensed, cross-platform agent workspace with mobile monitoring
- Teams mixing Claude Code and Codex who want one consistent session UI
Poor fit:
- Terminal purists who want a thin, fast layer over their existing setup (cmux fits better)
- Enterprises needing published team pricing, support SLAs, or governance features
- Developers wary of Electron resource usage or of a project whose open-source era began in April 2026
Viability Assessment
| Factor | Assessment |
|---|---|
| Financial Health | Unknown — Stravu's funding is not publicly disclosed; no published revenue model |
| Market Position | Early — official Crystal successor, but 795 stars trails category leaders[6] |
| Innovation Pace | Rapid — ten releases May 31–June 9, 2026; near-daily pushes[7] |
| Community/Ecosystem | Forming — Crystal's community is migrating; extension system invites contributions[5] |
| Long-term Outlook | Cautiously positive — full company commitment, but monetization and traction unproven |
Stravu has bet the company on Nimbalyst: it deprecated its 3,000-star predecessor outright rather than maintaining both.[1] The ship rate is high and the surface area (four desktop/mobile platforms, four agent engines, an extension system) is ambitious for a small team — which cuts both ways, as the 233 open issues suggest.[6] The open question is whether Crystal's community follows and whether an undisclosed paid tier can sustain development.
Bottom Line
Nimbalyst is the maintained continuation of the Crystal idea — parallel Claude Code and Codex sessions in git worktrees — wrapped in a more ambitious visual workspace with session kanban, WYSIWYG editing of plans and mockups, and an iOS companion, all MIT-licensed and free for individuals.[3][2] It is early: open-sourced only in April 2026, 795 stars, and little independent community discussion yet.[6]
Recommended for: Crystal users (migration is the official path), and developers who want free, visual, engine-agnostic multi-agent orchestration across macOS, Windows, Linux, and iOS.
Not recommended for: Terminal-first developers, enterprises needing published pricing and support, or anyone who wants a tool with a long open-source track record.
Outlook: Watch whether Crystal's 3,000-star community converts, whether star growth accelerates post-open-sourcing, and what Stravu announces for team pricing. The product is shipping fast; the market verdict is still out.
Research by Ry Walker Research • methodology
Sources
- [1] Crystal v0.3.5 Release Notes (Deprecation Notice)
- [2] Nimbalyst Website
- [3] Crystal for Claude Code: Nimbalyst is the Successor
- [4] HN: Nimbalyst WYSIWYG Markdown editor with visual diffs (closed-source era)
- [5] Show HN: Nimbalyst open-source visual workspace for ClaudeCode, Codex, OpenCode
- [6] Nimbalyst GitHub Repository
- [7] Nimbalyst Releases
- [8] SitePoint: Nimbalyst, the Visual Workspace for Building with Claude Code and Codex
- [9] HN: Local WYSIWYG Markdown, mockup, data model editor powered by Claude Code