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A cloud coding agent for your backlog. Assign a Linear issue or label a GitHub issue; it writes the code in an isolated sandbox, opens a pull request, runs your tests, and reviews its own diff. Free tier runs on your own Claude or Codex subscription.

Which is more popular?
Based on our record, CodeSandbox seems to be more popular. It has been mentioned 313 times since March 2021.
Website, pricing, platforms and company facts side by side.
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| Website | codesandbox.io | sinatra.dev |
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| Company | Startup from The Netherlands · 1 - 9 employees · 2017 | — |
| Listed in |
What each product offers, as listed by its team.


Possible disadvantages
No features have been listed yet.
An editorial look at what each product does well and who it suits.


Overall verdict
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No analysis of Sinatra.dev yet.
Walkthroughs and reviews on video.
A browser IDE that's actually GOOD? (CodeSandbox.io Review!)
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Sinatra demo: GitHub issue to pull request, end to end (22 seconds)
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How often each product is chosen within a category, 0–100% relative to the other.


As answered by people managing CodeSandbox and Sinatra.dev.
Sinatra.dev's answer:
It runs on the model subscription you already pay for. You assign a Linear issue or label a GitHub issue, the agent does the work in its own isolated sandbox and comes back with a pull request, and the model bill goes to your own Claude or Codex subscription or API key. We don't resell tokens or mark them up. The free tier is 5 tasks a day on your own credentials, every day, or 1 task a day where Sinatra covers the tokens. Pricing was the reason we built it in the first place, the agents we tried billed in credits you couldn't predict.
Sinatra.dev's answer:
Pricing and entry points. The paid plan is $20 per member per month for the hosted sandboxes and orchestration, with no markup on tokens because inference runs on your own Claude or Codex subscription or API key. And it works from Linear issues as well as GitHub, so a team whose tickets live in Linear can assign work to the agent the way they'd assign a teammate. It also reviews its own diff and posts the findings on the PR, and pushes revisions when a reviewer leaves comments. To be honest about the limits, it only works from GitHub and Linear issues today, and the agent never merges its own PRs, a person does that.
Sinatra.dev's answer:
Small engineering teams and solo founders with a backlog of well specified tickets they never get to: reproducible bugs, small features with acceptance criteria, the work that is clear enough to hand off but keeps getting pushed behind bigger things. Teams already working out of Linear or GitHub Issues who don't want another tool to learn, and who would rather run agent work on the Claude or Codex subscription they already have than open a new metered account somewhere else.
Sinatra.dev's answer:
I built a pet sitting marketplace with my wife. She always had features she wanted shipped and every one of them went through me, so I spent about three months building an agent she could assign tickets to instead. She writes the ticket, assigns it, and a PR comes back. She's now a big contributor to that codebase without me being in the way. I started handing it my own backlog too and eventually it turned into a product. It has been a lot harder to build than I expected, lots of edge cases, which is why it only works from Linear and GitHub issues right now and why the agent doesn't merge its own PRs, you still do that last part yourself.
Sinatra.dev's answer:
TypeScript throughout. A Fastify API for webhooks and OAuth, a Temporal worker that orchestrates each agent run, Next.js for the dashboard and the site, and Prisma on Postgres. Every task runs in its own Daytona sandbox that gets cloned, worked and torn down. Model access is bring your own: an Anthropic or OpenRouter API key, or a Claude or ChatGPT subscription connected to the workspace.
Share your experience with using CodeSandbox and Sinatra.dev. For example, how are they different and which one is better?
External articles and on-site reviews we used to compare the two products.


Codesandbox is an online code editor and prototyping tool that makes creating and sharing web apps faster. Codesandbox: Online code editor and ide for rapid web development.
CodeSandbox can be thought of as a much more powerful and complete take on JSFiddle. True to its name, CodeSandbox provides a complete code editor experience and a sandboxed environment for front-end development.
We have no reviews of Sinatra.dev yet. Be the first one to post
Recommendations tracked on public social media and blogs since March 2021.


To begin, you can start creating your own react app using the command line or can directly go to CodeSandbox if you want to skip using the command line which is faster. CodeSandbox is an online code editor and prototype tool that speeds... - Source: dev.to / 5 months ago
To begin, you can create a react app using the command line or any code editor (e.g., VSCode). You can also try using CodeSandbox as an online code editor that is simple to use and allows you to deploy your code. - Source: dev.to / 5 months ago
If you are in a rush to open unknown repos, use GitHub Codespaces or codesandbox with Copilot or another AI integration to analyze the repo for malicious intent and to run it in a safe environment. - Source: dev.to / 11 months ago
Tracking Sinatra.dev since Sep 2026.
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