Show HN: Fabro – open-source dark software factory (opens in new tab)

Hi — I created Fabro to free myself from supervising a fleet of Claude Code tabs running in a REPL (read-eval-prompt-loop). REPLs are great for exploration, but once I know what I need I want to be able to walk away while the agents get it done. (Before building Fabro, I looked for something off the shelf but couldn't find anything that was open source, hype-free, and full featured / ready.)

Fabro helps experienced engineers evolve towards a “dark” software factory where average time between disengagements increases. It’s easy to throw a Ralph shell script around Claude, but as runtime increases the chance of high quality output declines.

Fabro adds the last mile of guardrails to make it actually work: combining deterministic workflows of agents, commands like linters and test suites, with strategically applied human steering. (Similar to the Stripe's Minions.)

Fabro is multi-model and makes it easy to combine Claude, Gemini, and GPT in ensemble reviews — or delegate coding to faster and cheaper models like Kimi.

Software factories work best when combined with cloud VMs (like Daytona) so you get infinitely scalable, secure sandboxes that can run 24/7 and accessible via SSH, VS Code, and preview links as needed. This can be a bit of a pain to set up today and Fabro tries to make it as easy as Docker.

The closest analog to Fabro today would be something like Factory.ai Droids. However, I think it’s critical for engineers to own their own toolchain and so Fabro is open source (MIT) so you can fork it and customize it anytime.

The project is highly active and I’d love any feedback or feature requests. I’ll be on here answering questions today.

(Had posted this a week or so, hoping to engage in some conversation.)

-Bryan