Dagger
Portable CI/CD engine. Solomon Hykes (Docker creator), 2022. Write pipelines in Go/Python/TypeScript/Java instead of YAML. Run same pipeline locally + in all CI systems (GitHub Actions, GitLab, Jenkins).
Built on BuildKit (Docker's build engine). SDK-based: pipeline code in your language, Dagger engine runs actions in containers. Killer feature: faster CI via aggressive caching + parallel execution. Debugging: run pipeline locally, same code as CI = bugfix loop minutes instead of hours. Adoption challenge: new mental model vs YAML CI. v0.10+ adds module system for reusable pipeline components. Dagger Cloud is paid service for centralized trace monitoring + caching.