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Life & fun · February 10, 2025

Lapisla – A Theorem Proving Platform for Openness and Reusability

Hey HN! We built *lapisla*, a theorem proving platform designed to make formal proofs more open and collaborative. We developed a kernel, editor, proof registry, and platform ── all accessible directly in the browser. Why we built this: Existing theorem provers are powerful, but they often feel isolated and difficult to extend. Unlike modern programming languages, which thrive on package managers and shared libraries, theorem proving tools lack a seamless way to integrate others' work. lapisla aims to bridge this gap by: * Offering a verified public proof registry for sharing and discovering…

Lapisla – A Theorem Proving Platform for Openness and Reusability launched on February 10, 2025 with 6 votes and more than 75% of that year's launches. The site was still online in September 2026, 1 year on.

What it does

lapisla is a *battery-pluggable* theorem prover and ecosystem designed for everyone. Greetings! 👋 - lapisla-prover/lapisla-prover

Existing theorem proving assistants are often considered more difficult to use compared to "general" software development. We believe this is because popular programming languages have well-developed ecosystems that allow users to easily leverage others' work, whereas many theorem provers lack such a system. To address this, lapisla provides a fully browser-based kernel and UI, along with a registry, enabling seamless sharing and utilization of proofs. We call this ability to easily integrate others' work "battery-pluggable" , which is the core concept of lapisla ! lapisla is more than just a theorem proving assistant—it's a theorem proving platform! You can generate Permanent Links to…from github.com

In the maker’s words, at launch

Hey HN! We built *lapisla*, a theorem proving platform designed to make formal proofs more open and collaborative. We developed a kernel, editor, proof registry, and platform ── all accessible directly in the browser. Why we built this: Existing theorem provers are powerful, but they often feel isolated and difficult…

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