Summary

• add zigux/tests/phase1_bench_build_contract.zig as a focused Zig contract for the current Phase 1 bench build gate
• assert that phase1_bench_build.zig keeps the full helper module packet, including the bitmap -> find_bit dependency and root imports for bitmap, find_bit, hweight, list_sort, rbtree, and string
• assert the build shard keeps the phase1-bench executable, the bench and test routes, two run_bench step dependencies, and default-step handoff to test

Why This Lane

• Lane 16 owns Phase 1 hardening gates around bench-sensitive helper packets
• the benchmark packet and many replay runners are already active review fronts, so this adds a non-overlapping source-level guard for the build gate itself
• this keeps the direct bench route review-visible without reopening phase1_bench.zig, phase1_bench_build.zig, helper implementations, checker scripts, docs, fixtures, or workflows

Validation

• authenticated master...master compare grounded current master at 8bfbc83315f48dc5163b4ea4709ca38bb8cb5fe7; master later advanced to 3f4f3376ace76861515a789221b7a0c7467e4d86, and the branch was restacked onto that current head
• authenticated current-master reread confirmed zigux/tests/phase1_bench_build.zig has the current helper module packet and bench/test route surface
• authenticated current-master reread confirmed zigux/tests/phase1_bench_build_contract.zig returned 404 before publication
• focused scratch validation used the attached Zigux-master.zip scaffold plus the attached Zig 0.17.0-dev.87+9b177a7d2 toolchain because direct live checkout remains unavailable in this scheduled runtime
• overlaid the exact current phase1_bench_build.zig source from GitHub into scratch for the embedded-file contract check
• zig fmt --check zigux/tests/phase1_bench_build_contract.zig zigux/tests/phase1_bench_build.zig
• zig test zigux/tests/phase1_bench_build_contract.zig
  • result: All 2 tests passed.
• authenticated compare after final restack:
  • changed files: 1
  • result: ahead_by: 1
  • result: behind_by: 0
  • result: status: ahead

Scope

• lane: Lane 16 — Phase 1 hardening gates
• session issue: Zigux session 2026-05-29 15:32 UTC #15303
• branch: zigux-builder/lane16-phase1-bench-build-contract-20260529t1540z
• file:
  • zigux/tests/phase1_bench_build_contract.zig

Coordination

• keep PR test(zigux): add lane16 bench output contract runner #15254 as the separate bench output contract runner frontier
• keep PR test(zigux): add lane16 phase1 bench output contract #15033 as the separate bench output contract body frontier
• keep replay runner PRs such as test(zigux): add lane16 find_next_and_bit bench runner #15091, test(zigux): add lane16 findNextAndBit replay runner #14977, test(zigux): add lane16 rbtree findAddCached replay runner #14922, test(zigux): add lane16 rbtree findAdd replay runner #14806, test(zigux): add lane16 rbtree postorder replay runner #14749, test(zigux): add lane16 bitmap-window bench replay runner #14688, test(zigux): add lane16 rbtree cached bench replay runner #14628, test(zigux): add lane16 rbtree duplicate mutation replay runner #14569, test(zigux): restack lane16 hweight bench replay runner #14511, test(zigux): restack lane16 list_sort bench replay runner #14450, test(zigux): add lane16 rbtree bench replay runner #14329, test(zigux): add lane16 find_next_bit bench replay runner #14266, test(zigux): add lane16 find_bit bench replay runner #14147, test(zigux): add lane16 find_next_and_bit bench replay runner #14090, test(zigux): add lane16 find_next_zero_bit bench replay runner #14031, test(zigux): add lane16 string bench replay runner #13972, and test(zigux): add lane16 find_bit edge bench replay runner #13915 on their separate paths
• keep checker and workflow fronts untouched

Validation Boundary

Direct live checkout remains unavailable in this scheduled container due CONNECT tunnel failed, response 403, so live repo grounding and publication used authenticated GitHub reads/writes plus focused scratch validation.