The Apakkalypse: migrating off Akka

On September 7, 2022, Lightbend announced a license change to Akka. Existing Akka versions (latest: 2.6.20) may still be used freely under the Apache 2.0 License. The new Business Source License will apply beginning in September 2023.

Impacts of the license change

• Versions covered under the BSL have a sticker price of $1,995 per core per year.
• No security patches or bugfixes will be released under a free license beginning in September 2023.
• Because all future patches will be released under a BSL, it is unclear that we can backport any critical fixes without doing a clean room implementation. This is a more severe position than being on an EOL version, where community fixes may be retrofit.
• A community fork is possible, but will not be published to the same Maven Organization. This will require either a (breaking) package change, or tricky transitive dependency exemptions.
• There exists an Additional Use Grant for open source that depends on Akka. This is already granted to the Play Framework. There are open questions about whether such projects remain open source.

Edicts

• No greenfield projects will depend on Akka. Don’t make the mountain bigger.
• Teams running a brownfield project with an Akka dependency need a migration plan.
• Don’t panic, but don’t be complacent. This is worse than your typical community EOL.

Alternatives

We have been successful replacing many Akka modules with the Typelevel stack. Ask for advice on #sig-scala. If your team doesn’t have time or expertise, we will allocate Staff Engineers to help.