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Berlin Scala Spree 2018

Eugene Yokota Scala Team, Lightbend, Inc.

Hi everyone. Berlin is my favorite city to visit in the early summer. I like the square-looking buildings in faded pastels, and the lush patios that it hides. Long days of sunlight, and people hanging out in the parks. I like the network of trams and U-Bahn subway that has no gates to check for tickets, taking you to Vietnamese restaurants and cafes. Spicy döner kebab in crisply toasted Turkish bread.

Berlin Scala Spree

As a side event to Scala Days Berlin, the Scala Center and Zalando hosted a Scala Spree on May 15th. A Scala Spree is a hackathon event where you work on an OSS Scala project with a representative of that project (usually a maintainer) to send one (or more!) pull request(s) and thus becoming a Scala contributor. The Lightbend Tooling Team attended it representing sbt, alongside other OSS projects like Dotty, Scala, and Scalameta. So many contributors signed up for sbt, that we had to put two tables together!

To be contributor friendly we’ve been improving our Contributor Guide, and the first thing we went through at the Scala Spree was building sbt from source.

Another thing we did to prepare for the Scala Spree was tagging GitHub issues with the “help wanted” and/or the “good first issue” labels, and writing out mentoring instructions which include relevant links, hints as to how to resolve the issue and testing tips. The attendees picked out the issues they wanted to work on, and at the end of the day, we got eight pull requests:

  • Removes use of deprecated ModifiedTime methods. io#154 by Daniel Westheide (@kaffeecoder)
  • Migrated last command strings to camelCase. #4159 by Alexander Samsig (@ASamsig)
  • Fixes help -v rendering of multi-line descriptions. #4160 by Øyvind Høisæther (@ninjalama)
  • Fixes packageBin not creating file when deleted. #4161 by Jannis Eichborn (@JEichborn)
  • Fixes –error etc to set log level. #4162 by Holden Karau (@holdenkarau)
  • Removes compiler warnings introduced with Scala 2.12. #4163 by Daniel Westheide (@kaffeecoder)
  • Improves loading settings messaging. #4164 by Aloisia Davì (@alo_davi)
  • Recovers “Resolving…” log under UpdateLogging.Full. lm#240 by Håkon Wold (@hodga)

We had a lot of fun working with these first-time contributors, and learned a bunch too. Through these events we hope to show that sbt is just another Scala project, and that making changes isn’t as difficult as you might think it is.

Here’s from Daniel:



Thanks Scala Center and Zalando for this great opportunity!

sbt 1.1.6 patch release

We are also happy to announce the sbt 1.1.6 patch release!

As a reminder, sbt 1 is released under Semantic Versioning. So plugins released for 1.0.x will continue to work throughout 1.x including 1.1, 1.2, etc.

Bug fixes


A huge thank you to everyone who’s helped improve sbt and Zinc 1 by using them, reporting bugs, improving our documentation, porting builds, porting plugins, and submitting and reviewing pull requests.

sbt 1.1.6 was brought to you by 15 contributors, according to git shortlog -sn --no-merges v1.1.5...v1.1.6 on sbt, zinc, librarymanagement, util, io, launcher-package, and website: Ethan Atkins, Eugene Yokota, Dale Wijnand, Aaron S. Hawley, OlegYch, Richard Summerhayes, Jannis (dadarakt), Rikito Taniguchi (tanishiking), Øyvind Høisæther, Daniel Westheide, Harrison Houghton, Holden Karau, Håkon Wold, Jason Zaugg, and tekay.

For anyone interested in helping sbt, there are many avenues you could help, depending on your interest.

  • Migrate library builds to sbt 1, or update plugins.
  • Report bugs when you see them.
  • Send in fixes to bugs.
  • Update documentation.

If you’re interested in other ideas, come talk to us on sbt-contrib or on Lightbend Discuss.


The Total Economic Impact™
Of Lightbend Akka

  • 139% ROI
  • 50% to 75% faster time-to-market
  • 20x increase in developer throughput
  • <6 months Akka pays for itself