How-to: build a specific MuJoCo version/ref

Build

From the repo root (in WSL/Linux):

python3 forge_cli.py build --version 3.5.0

--version is passed to the upstream MuJoCo checkout under external/mujoco, so it can be:

a released tag like 3.5.0,
a branch name,
a commit hash.

Outputs

Successful builds populate:

dist/<ver>/mujoco.js
dist/<ver>/mujoco.wasm
dist/<ver>/abi/* (introspection + export/ABI manifests and reports)

Build directory placement (recommended on synced filesystems)

By default, the forge CLI uses <repo>/build for intermediate build output. To move build trees elsewhere:

MJWF_BUILD_ROOT=/tmp/mjwf_build python3 forge_cli.py build --version 3.5.0

Clean rebuild

If you want to force a full re-clone of upstream MuJoCo, remove external/mujoco and rebuild. The directory is not tracked by git in this repo, and the forge CLI will recreate it on demand.