build

---

name: build description: Builds the GenVM project. Use after making code changes to compile Rust binaries.

To build the GenVM project:

Build all Rust binaries:

Copynix develop .#full --command bash .claude/skills/build/run-ninja.sh -C build all/bin

This runs ninja silently and only shows output on failure (to save tokens).

Available ninja targets:

Output locations:

• out/bin/genvm-modules - modules binary
• out/executor/vTEST/bin/genvm - executor binary

Runners

Runners can only be built on x86_64 using the all target. On other platforms, download them instead.

Download runners:

Copynix develop .#full --command python3 build/out/bin/post-install.py --create-venv false --default-step false --runners-download true --error-on-missing-executor false

Runner Development Workflow

To develop/modify a runner (e.g., cloudpickle):

1. Enable dev mode: Set runners/support/current/dev-mode.nix to true

2. Set hash to "test": In runners/support/current/hashes.nix, set the runner's hash to "test"

3. Make your modifications and run tests With dev-mode enabled and hash set to "test", you can build and run tests.

4. Disable dev mode: Set runners/support/current/dev-mode.nix back to false. The build will now tell you to set hashes to null.

5. Set hashes to null and build: Set the runner's hash (and dependent runners' hashes) to null, then build:

   Copynix develop .#full --command ninja -C build all
   

   The build will fail with a hash mismatch showing the new hash.

6. Update hashes: Copy the new hash from the error message back into hashes.nix. Repeat for dependent runners.

7. Rebuild to verify: Run the build again to confirm all hashes are correct.