Right, we can only use it if the version is bumped. However, bumping the version is usually done as part of a release of the izettle-toolbox, and not usually part of each PR. The usual workflow that we've been doing is like this:
1. Let's say the last released version is currently `1.2.3` , and the working version in this repo is then `1.2.4-SNAPSHOT`.
2. Do lots of clever changes to the toolbox. These will all be done in `1.2.4-SNAPSHOT`.
3. Some other program wants to use the new stuff developed in `1.2.4-SNAPSHOT`. This will require a release of the toolbox
4. Do a release of the toolbox. This includes creating a commit with only version bumping and tagging. The version will then be bumped to `1.2.4`. The jar will be uploaded to artifactories.
5. Version will then be bumped to `1.2.5-SNAPSHOT`.
6. Other systems can now use new functionalities from toolbox `1.2.4`.
7. Goto 2.

Hope that explains it :)