Mojo Is Now Open Source: Modular Opens the Compiler Under Apache 2.0
Modular has open-sourced the Mojo compiler, tooling and build system under Apache 2.0 with LLVM exceptions, days after Mojo 1.0. What the move means for GPU-ready AI infrastructure.
What happened
Modular has released the Mojo programming language as fully open source under the Apache 2.0 licence with LLVM exceptions. The compiler, the tooling and everything needed to build the language now sit in the company's public modular GitHub repository — four years after Mojo was first unveiled, and days after it reached version 1.0 with source stability.
Why it matters
Mojo was built by Chris Lattner's team to go beyond older languages: it blends modern compiler research with a Python-like syntax to unlock GPUs, AI accelerators and other advanced compute. With an open compiler, anyone can read, modify and rebuild the entire toolchain — and Apache 2.0 is the permissive standard used by many mainstream languages, with the LLVM exceptions widening the freedom to ship binaries.
What is still closed
Modular is not yet accepting outside contributions to the compiler and tooling; the target is by the end of this year. The standard library has taken community contributions since 2024. For AI infrastructure teams, a GPU-ready language with an open compiler lowers the barrier to high-performance compute work.