dirlir

antlir2's architecture (features → depgraph → layers, resolve/materialize split, userns isolation) transplanted onto Nix + Buck2, producing plain directory trees instead of container images. Nix packages become buck2-native artifacts (downloads hash-verified by buck2 itself against signed, locked NarHashes); toolchains (gcc, ghc) and native deps (openssl) run enclosed in minimal namespaces by default, identically on the local machine and on remote-execution workers that have no nix, no store, and no host tooling at all.

See DESIGN.md for the architecture and the guarantee→test matrix, PLAN-v2.md for the v2 plan and ADRs.

Quickstart

nix develop                                  # buck2 (from source, patch-ready), python3, jq

buck2 build root//...                        # everything, enclosed by default
buck2 run root//examples/tls_demo:main       # gcc + openssl, hermetically
buck2 build -c dirlir.isolation=off <t>      # per-invocation escape hatch
buck2 build -c dirlir.isolation=audit <t>    # observe instead of deny

# rung 0 — wrap any build (daemon included) in a store-masked namespace:
tools/dirlir-run -- buck2 build root//...
tools/dirlir-run --audit -- buck2 build root//...

# refresh / extend the package lock (signed narinfo walk over snix):
tools/resolve.sh

Proofs (all in CI: ci.yml per push, nightly cold+full, weekly liveness)

./tests/hermetic.sh          # full rebuild, host store masked to build infra
./tests/re-demo.sh           # NativeLink RE: store-less worker, symlink round-trip first,
                             #   every dirlir action remote (local count: 0)
./tests/enclosure.sh         # mask semantics, failure-UX trailer, per-mode digests
./tests/determinism.sh       # double build + cross-machine golden manifests
./tests/offline.sh           # everything re-runs without network (downloads excepted)
./tests/tamper.sh            # flipped locked hash -> rejected, no artifact
./tests/isolate-audit.sh     # strace: compiles touch nothing outside minimal roots
./tests/depgraph-errors.sh   # plan-time validation failures

Layout

• nix/resolve.py + nix/ed25519.py → nix/lock.{json,bzl} — signed, evaluation-free lock
• nix/shim/ — dirlir-shim (provision/enclose/exec) and nar-unpack, static musl
• nix/buck2/ — buck2 from source at a pinned rev, carried patches
• dirlir/ — rules: per-path artifacts, nix_closure, dir_layer, shim_run, bootstrap
• toolchains/, layers/ — hermetic cxx/haskell toolchains and the layer definitions
• tools/dirlir-run — rung-0 wrapper; tests/ — the guarantee suite