Show HN: FizzBee – Formal Model based autonomous testing

Show HN (score: 5)
Found: October 07, 2025
ID: 1754

Description

Testing
Show HN: FizzBee – Formal Model based autonomous testing GitHub: https://github.com/fizzbee-io/fizzbee-mbt-examples Quick Start: https://fizzbee.io/testing/tutorials/quick-start/

Most developers agree testing is important. At the same time, most developers don’t enjoy writing tests. With AI generating code faster than ever, testing is becoming even more crucial. But even AI-generated tests need review and maintenance, which makes them another burden.

I'm introducing another form of autonomous testing - "model-based testing". Instead of writing test cases, you describe expected behavior in a Python-like specification language.

The FizzBee model can be: - Verified exhaustively for design bugs (like formal methods). - Mapped to your actual system, automatically generating the tests.

This gives you:

- No hand-crafted test cases - Automatic testing of concurrent as well as sequential behavior - No cascading test rewrites when behavior changes - No cluttering the SUT with tracing code

With FizzBee, you get both design validation (like in formal methods) and automatic test generation, saving time and effort.

Currently, only Go is supported. Java and Rust are next and would love to hear which language you’d want supported next.

I’d love your feedback!

More from Show

Show HN: Widen – Open-source Mac Postgres GUI with local or cloud text-to-SQL

Show HN: Widen – Open-source Mac Postgres GUI with local or cloud text-to-SQL Github: <a href="https:&#x2F;&#x2F;github.com&#x2F;betocmn&#x2F;widen" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;betocmn&#x2F;widen</a><p>I was paying for DataGrip for several years as my desktop database GUI but if I wanted text-to-SQL with LLMs I&#x27;d have to pay even more on top. So I decided to build my own and I&#x27;ve been using it for a few weeks now.<p>At any time I&#x27;m usually working with 3 to 6 databases, and having them set up in something like Conductor (for parallel agentic coding), but for Postgres databases, lets me quickly start a session, ask questions to my database in plain English, get a data export, move on and close the session. It&#x27;s been working well and I thought I would share it here.<p>It&#x27;s a native Mac app (Swift), free and open source (MIT). For the LLM you bring your own OpenRouter key, or there&#x27;s an experimental on-device mode using Apple&#x27;s local model, where nothing leaves your Mac. Cloud mode only sends the question and schema metadata, not your data, unless you explicitly turn that on per connection.

No other tools from this source yet.