OpenC3 COSMOS 5.1.1 - Modern, Production Ready, Command and Control

Welcome to OpenC3 COSMOS 5.1.1!

This release is quick patch release to address the following:

Highlighted Improvements In This Release

  • ScriptRunner scripts can now handle unicode characters
  • Updated TextLogMicroservice to ensure a clean shutdown

Key Bug Fixes

  • Updated openc3.bat and openc3_util.bat to fix some issues on Windows with cli, cliroot, and util scripts

All Pull Requests in this Release

  • Windows cli use .env file by @ryanmelt in #272
  • Clean shutdown for TextLogMicroservice. Don’t enforce time ordering for text logs by @ryanmelt in #274
  • Handle UTF8 strings better when JSON encoding by @ryanmelt in #276

Prerequisites: Docker - Running OpenC3 requires a working Docker or Podman installation. Typically Docker Desktop on Windows / Mac. Plain Docker or Podman also works on linux. We actively develop and run with Docker Desktop on Mac/Windows, and Linux on Raspberry Pi, so if you have any issues on another platform, please let us know by submitting a ticket!

Minimum Resources allocated to Docker: 4GB RAM, 1 CPU, 80GB Disk Recommended Resources allocated to Docker: 16GB RAM, 2+ CPUs, 100GB Disk Also requires docker compose version 1.27+

To Run:

  • git clone cosmos-myproject
  • cd cosmos-myproject
  • Run Linux/Mac: ./ run
  • Run Windows: openc3.bat run
  • Connect a web browser to http://localhost:2900/
  • Have fun running OpenC3 COSMOS!

Please see our documentation at

Try it out and let us know what you think! Please submit any issues as Github tickets, or any generic feedback to


Full Changelog: Changelog