License Keys

While Skip’s libraries are free and open source, the Skip transpiler and tools require a license key when they are running on non-free or closed-source code.

During the Skip Technology Preview, you can request and renew a free 30-day license key from the the evaluation page.

License key workflow:

  • Skip is free to try. Installing Skip automatically begins a 14-day trial period.
  • When your trial period approaches its end, Skip will prompt you to obtain an evaluation license, which you can do from Your evaluation license is also free.
  • When your evaluation period is ending, Skip will prompt you to purchase a license online. The license key is node-locked to a single developer machine, so you will need to provide the output of the skip hostid command for the machine.

To obtain an evaluation key, visit the Skip Evaluation page.

After obtaining a license key, enter it in the ~/.skiptools/skipkey.env file, which is created when you install Skip:


The tools will also check the SKIPKEY environment variable for a valid key, which can be useful in continuous integration build environments.

Note that while using Skip’s tools requires a valid license key for non-free software, your apps do not. Skip is strictly a development tool, not a runtime. Your apps do not bundle a Skip license or perform any Skip license checks at runtime. All of your source code - including any previously transpiled Kotlin - is your own, regardless of whether your license is current.