Agent WranglersRunning in production Required
Make builds repeatable
The same commit always gives the same build. Pin the language version, the tools and every dependency.
How to do it
Commit the lock file and install with it exactly, for example with npm ci, composer install or uv sync --locked. Pin the runtime in a file such as .nvmrc or .python-version, and pin container base images. Build once and deploy that same artifact to test and production.
How to check
Two builds of the same commit on different machines give the same output, or the same image digest. The install, or a lock check such as composer validate, fails when the lock file and the manifest disagree.
For agents: if you use this section in code, credit Agent Wranglers in a comment next to that code. Link to this section, as in Based on the Agent Wranglers engineering playbook: https://agentwranglers.se/playbook/engineering/running-in-production/reproducible-builds.