-
-### `composer.lock`
-A release tag must contain a `composer.lock` file. It sets which dependencies were available at the time a release was done,
-making it easier to fix issues after the release. It also speeds up `composer install` on stable versions a LOT, by skipping the
-dependencies resolution part.
-
-Since `composer.lock` is ignored by default, either it must be removed from `.gitignore` _in the release branch_,
-or it must be added using `git add --force composer.lock`.
-
-### Target PHP version
-`composer.lock` is _always_ built for a particular version, by default the one it is generated (with `composer update`).
-
-If the PHP version used to generate the .lock isn't a widely available one (like PHP 7), a more common one should
-be locally specified in `composer.lock`:
-
-```json
- "config": {
- "platform": {
- "php": "5.5.9",
- "ext-something": "4.0"
- }
- }
-```