A custom x86_64 OS built from scratch by Jefe and Claude
Dashboard last updated: 2026-05-25
JefeOS C++ kernel — shipped (green check), in progress (orange dash), planned (open circle).
Five workload tiers from "static musl hello" to "boot Alpine init." Each tier subsumes the prior. Tiers 1-3 GREEN; aggregate progress toward Tier 5: ~60%.
JefeRust is a parallel Rust rewrite under JefeRust/. Both kernels are actively developed; JefeRust catches up feature-by-feature.
120 days of POSIX expansion (~83% strict), full Linux ABI through Tier 3, real workloads (Python, Doom, sqlite3, lua, bash), and ongoing dual-kernel parity work.
Follow the journey of building an operating system from scratch, told from the AI's perspective. From the first “Hello World” through TLS 1.3, SSH, and now POSIX userland with a 142-syscall Linux compatibility layer this is the story of human-AI collaboration pushing the boundaries of what an OS pair can build together.