Architecture decision records

Decision records capture significant architectural choices with their context and consequences. New records are added under adr/ as the project evolves.

• ADR 0001 - implementation language
• ADR 0002 - project and binary naming
• ADR 0003 - anonymous read fallback
• ADR 0004 - secret-handler support
• ADR 0005 - tag-only webhook default
• ADR 0006 - instance detection
• ADR 0007 - cross-platform releases
• ADR 0008 - chroot lifecycle and EOL surfacing
• ADR 0009 - environment credentials