TDGS-2: Trinity Caste System — Enforce L0/L1 Independence in build.zig #412

TDGS-2: Trinity Caste System — Enforce L0/L1 Independence in build.zig

Context

Following TDGS-1 (Tri Dev Guarded Stack), we need to enforce architectural invariants in the build system: L0 (Temple) and L1 (Queens) must build independently of L2-L3 (Workers/Foragers).

Current Problem

The tri binary has a circular dependency: Queen depends on tri_farm/tri_fpga which should be "consumable" workers. If one worker fails to compile, the entire tri build fails — breaking the caste system invariant.

Required Changes

1. Create Caste-Aware Build Targets

Add targets to build.zig:

• zig build temple — L0 only (TTC, math, VSA, types)
• zig build queens — L1 only (Queen, Doctor, Scheduler)
• zig build workers — L2 only (tri_farm, tri_fpga, inference)
• zig build tri — All castes (for backward compatibility)

2. Zig 0.15 Build API Migration

The build.zig needs migration from Zig 0.13 → 0.15 API:

Old (0.13):

b.addExecutable(.{
    .name = "foo",
    .root_source_file = b.path("foo.zig"),
    .target = target,
    .optimize = optimize,
})

New (0.15):

const foo_mod = b.createModule(.{
    .root_source_file = b.path("foo.zig"),
    .target = target,
    .optimize = optimize,
});
b.addExecutable(.{
    .name = "foo",
    .root_module = foo_mod,
})

This affects 275+ occurrences across build.zig.

3. Architectural Separation

• Temple (L0): src/vsa.zig, src/sacred/, src/hybrid/
• Queens (L1): src/tri/doctor/, src/tri/main.zig (Queen routing)
• Workers (L2): src/tri/tri_farm.zig, src/tri/tri_fpga.zig
• Foragers (L3): Train tasks, benchmarks

Success Criteria

1. zig build queens succeeds even if tri_farm.zig has syntax errors
2. zig build temple compiles in <5 seconds (minimal dependencies)
3. Doctor daemon can be built independently: zig build doctor

Files to Modify

• build.zig — Add caste-aware targets, migrate to Zig 0.15 API
• Possibly: src/tri/main.zig — Split Queen routing from worker commands

References

• CLAUDE.md: "Trinity S³AI — Temple, Brain & φ-Structure"
• TDGS-1: Issue #XXX (Tri Dev Guarded Stack)
• Plan file: /Users/playra/.claude/plans/nifty-shimmying-widget.md

Generated from: tri doctor diagnose
Date: 2026-03-24T18:58:23Z
Priority: High (unblocks Queen + Doctor independence)