The first community organized and hosted Dev Camp completed and was an amazing success in both quantitative and qualitative terms. The Cryptographic Autonomy Licence that we’ve supported for months is now officially an OSI open-source license that protects end-users from having their data held hostage! And the latest version of Holochain has been released as we continue measuring and tuning performance.


  • Recap from Dev Camp 6
  • Cryptographic Autonomy License approved by OSI
  • Holochain v0.0.43-alpha3 released
  • Performance measurement and tuning continues

As always, you can see our dev progress both on our website dashboard and Github repositories for Holochain.

Recap from DevCamp 6

As mentioned in the last Dev Pulse 64, we were blown away by the Holochain community that organized, hosted, and participated in the largest online DevCamp to date! That multi-day camp finished yesterday on a high note—during the closing call, participants shared about their happy experiences, their appreciation for the facilitators, and their eagerness to keep working on their own projects. Well over 200 people registered for the course, and the group calls regularly saw 60 people in attendance with more people watching the recordings.

During the course, participants learned how to use Holochain’s building blocks as they created a Udemy-like online learning app called Learning Pathways (LeaP). You can find the source code in the GitHub repository, where development is continuing. If you’d like to get started building a Holochain app with others, this would be a great project to contribute to!

New to this dev camp was a pair of networking calls, where creators shared about their projects and interests and connected with each other. This sort of cross-pollination is encouraging to see, because we believe that the Holochain developer ecosystem will thrive when people pool their needs and abilities to work on common tools, libraries, and initiatives. We’ve opened up the New Projects category on the forum to continue this conversation; we’d love to see you there.

We’d like to thank the Dev Camp organizers for their generous devotion to making this a reality: Adriaan, Hedayat, Guillem, Karl, Raphi, and Thomas.

Cryptographic Autonomy License approved by OSI

After a long review period (and a little controversy) the Open Source Initiative (OSI), the most widely recognised advocacy group for open-source, has approved our Cryptographic Autonomy License (CAL). It’s now an officially recognized open-source license! The CAL protects end-users by prohibiting licensees from holding their data hostage. We’ve already updated the Communities hApp to reflect its new CAL status. And now that this license is approved, we’ll be relicensing the vast majority of Holochain’s core components under it as soon as possible.

Holochain v0.0.43-alpha3 released

This release has some exciting features that we’d love to share and get some feedback on.

  • Pagination and sorting of links—you can retrieve links in batches, either with the traditional page-size-and-number technique or a timestamp-based technique. You can also sort results by committed timestamp, oldest-first or newest-first.
  • Improvements to sim2h_server and Holochain itself mean that everything is much faster; this is the version that hit the fabled 5000-node goal!

Breaking changes

  • In order to accommodate pagination and sorting, the call signatures for get_links and friends have changed.
  • If you run the new sim2h_server, all agents will need to run the new conductor as well. This is because of a change in the way Holochain announces membership in a DNA space.
  • sim1h and n3h were obsolete and unmaintained for a while; we’ve now removed them as supported networking backends.

Known issues

  • We’re seeing intermittent timeouts with send/receive.
  • A regression causes sim2h to halt or drop gossip traffic under heavy load.

Note: We are seeing some intermittent odd behavior on this release with sim2h gossiping, and timeouts on direct messages, for this reason we haven't blessed this version on holonix. Please give us feedback on your experience.

Performance measurement and tuning continues

As mentioned in the last Dev Pulse, the core team are deep into performance work. They’ve put tracing hooks into many parts of the codebase to detect and analyze bottlenecks. They’re using Jaeger, a tool for measuring the performance of complex distributed systems. Experimental work also continues on integrating a new WebAssembly engine which should bring substantial speed improvements and a simplified codebase.

Holochain Core Concepts and Tutorials

We want to hear from you! Help us create documentation that would benefit your understanding of Holochain and aid you in building apps. If you have already read, explored, or completed the Holochain Core Concepts and Tutorials, we would appreciate your input through this quick survey! Please take a moment to tell us about your experience and how we might help you further!

Development Status


Blessed (available via

  • Holonix: 0.0.62
  • Holochain Core: 0.0.42-alpha5