Leo

Judgement

What it is

Developer tool

What it does

The compiler for Leo, a statically typed language for writing private zero-knowledge applications on the Aleo blockchain.

Adopt it when

You are building privacy-preserving applications specifically on Aleo.

Watch out

Tied to one blockchain ecosystem, and GPL-3.0 licensed.

Ready for

Usable

Runs as

Command line

Built with

Rust

How established

Established: started 6 years ago, latest release leo-lang-v4.4.6.

What the license allows

Use inside your business is unrestricted, but anything you distribute that includes it must be released under the same license.

Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: Leo → Rust → runs on a microchip

How compilers were built, back to punched paper tape

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