AWS Nitro API Co-signer Version History

Fireblocks updates the API Co-signer software to include stability enhancements and new features. This article details the most recent AWS Nitro Co-signer versions. Always use the latest version listed here for optimal performance.


Latest version

Version 2025.08.12 (August 2025; US environments only)

Version hash: 19c07421dc

  • Fixed WebSocket bug causing performance issues

Version history

Version 2025.07.16 (July 2025)

Version hash: bb61e507

  • Fixed bugs and increased performance
  • Better support for web sockets

Version 2.1.1 (April 2025)

Version hash: 7160d7b833

  • Bug fixes and performance improvements

Version 2.0.5 (September 2024)

Version hash: d177e696c3

  • Decreased signing latency along with general performance increases
  • Extended filtering of environment variables
  • Improvements to key handling within the enclave
  • Bug fixes

Version 2.0.4 (August 2024)

Version hash: 41d1888dc8

  • Fixed the issue when setting AWS region using environment variables
  • Removed unnecessary testing artifacts

Version 2.0.2 (August 2024)

  • Modified KMS CMK ARN prompt
  • Added start, stop and restart commands
  • Added echo to show where logs are saved to
  • Fixed AWS NTP sync issue
  • Fixed Callback Handler public key issue on install
  • Removed unnecessary testing artifacts

Version 2.0.1 (July 2024)

  • Added check for force flag and existence of destination before the user is prompted for details
  • Added route DNS queries to the DNS server defined on the host EC2 instance

Version 2.0.0 (June 2024)

  • Initial release