Compiler Orchestrator

Compiler Orchestrator

Automatically drive the Rust compiler port forward by discovering the current state, fixing failures, porting new passes, reviewing, and committing — in a continuous loop.

Arguments:

• $ARGUMENTS: Optional. A pass name to start from, or status to just report current state without acting.

Pass Order Reference

These are the passes in Pipeline.ts order, with their exact log names:

Validation passes (no log entries, tested via CompileError/CompileSkip events):

• After PruneMaybeThrows (#2): validateContextVariableLValues, validateUseMemo
• After InferTypes (#9): validateHooksUsage, validateNoCapitalizedCalls (conditional)
• After InferMutationAliasingRanges (#16): 8 validators (conditional)
• After InferReactivePlaces (#17): validateExhaustiveDependencies (conditional)
• After RewriteInstructionKindsBasedOnReassignment (#18): validateStaticComponents (conditional)
• After PruneHoistedContexts (#45): validatePreservedManualMemoization (conditional)
• After Codegen (#46): validateSourceLocations (conditional)

Orchestrator Log

Maintain a log file at compiler/docs/rust-port/rust-port-orchestrator-log.md that tracks all progress.

Log file format

# Status

HIR: complete (1717/1717)
PruneMaybeThrows: complete (1717/1717)
DropManualMemoization: complete (1717/1717)
...
AnalyseFunctions: partial (1700/1717)
InferMutationAliasingEffects: todo
...

# Logs

## 20260318-143022 Port AnalyseFunctions pass

Ported AnalyseFunctions from TypeScript to Rust. Added new crate react_compiler_analyse_functions.
1700/1717 tests passing, 17 failures in edge cases with nested functions.

## 20260318-141500 Fix SSA phi node ordering

Fixed phi node operand ordering in SSA pass that caused 3 test failures.
All 1717 tests now passing through OptimizePropsMethodCalls.

Status section

The # Status section lists every pass from #1 to #49 with one of:

• complete (N/N) — all tests passing through this pass
• partial (passed/total) — some test failures remain
• todo — not yet ported

Update the Status section after every test run to reflect the latest results.

Log entries

Add a new log entry (below the most recent one, so newest entries are at the bottom) whenever:

• A pass is newly ported
• Test failures are fixed
• A commit is made

Entry format: ## YYYYMMDD-HHMMSS <short-summary> followed by 1-3 lines describing what changed.

Use the current timestamp when creating entries. Get it via date '+%Y%m%d-%H%M%S'.

Initialization

On first run, if the log file doesn't exist, create it with the Status section populated from the current state (read pipeline.rs and run tests to determine pass statuses).

Core Loop

Main context role: The main context is ONLY an orchestration loop. It parses subagent results, updates the orchestrator log, prints status, and launches the next subagent. The main context MUST NOT read source code, investigate failures, debug issues, or make edits directly. ALL implementation work — fixing, porting, reviewing, verifying — happens in subagents.

Execute these steps in order, looping back to Step 1 after each commit:

Step 1: Discover Frontier

Run test-rust-port with --json to get machine-readable results:

bash compiler/scripts/test-rust-port.sh --json 2>/dev/null

This outputs a single JSON object with fields: pass, autoDetected, total, passed, failed, frontier, perPass, failures.

Parse the JSON to extract:

• passed, failed, total counts
• frontier — the earliest pass with failures, or null if all clean
• perPass — per-pass breakdown of passed/failed counts

If frontier is null, determine the next action:

• The pass field shows the last ported pass (auto-detected from pipeline.rs)
• Look up the next pass in the Pass Order Reference table
• Otherwise, the mode is PORT for that next pass

If frontier is a pass name, the mode is FIX for that pass. Use --failures to get the full list of failing fixture paths:

bash compiler/scripts/test-rust-port.sh <FrontierPassName> --failures

Then run specific failing fixtures to get diffs for investigation:

bash compiler/scripts/test-rust-port.sh <FrontierPassName> <fixture-path> --no-color

Also check if compiler/docs/rust-port/rust-port-orchestrator-log.md exists. If not, create it with the Status section populated from the current state.

Update the orchestrator log Status section, then proceed to Step 2.

Step 2: Report Status

Print a status report:

## Orchestrator Status
- Ported passes: <count> / 49
- Test results: <passed> passed, <failed> failed (<total> total)
- Frontier: #<num> <PassName> (<FIX|PORT> mode) — or "none (all clean)"
- Action: <what will happen next>

If $ARGUMENTS is status, stop here.

Step 3: Act on Frontier

Do NOT investigate, read source code, or debug in the main context. Always delegate to a subagent.

3a. FIX mode (frontier is a ported pass with failures)

Launch two subagents in parallel to diagnose the failures:

1. Review subagent: Run /compiler-review on the failing pass to identify obvious issues — missing features, incorrect porting of logic, divergences from the TypeScript source.

2. Analysis subagent: A general-purpose subagent that investigates the actual test failures. Its prompt MUST include:

   • The pass name and its position number
   • The full test failure output (copy it verbatim)
   • Instructions: Run failing fixtures individually with bash compiler/scripts/test-rust-port.sh <PassName> <fixture-path> --no-color to get diffs. Analyze the diffs to determine what the Rust port is doing wrong. Read the corresponding TypeScript source to understand expected behavior. Report findings but do NOT make fixes yet.
   • Architecture guide path: compiler/docs/rust-port/rust-port-architecture.md
   • Pipeline path: compiler/crates/react_compiler/src/entrypoint/pipeline.rs

After both subagents complete, synthesize their results to determine a plan of action. The review may surface porting gaps that explain the test failures, and the failure analysis may reveal issues the review missed. Use both inputs to form a complete picture.

Then launch a single general-purpose subagent to fix the failures. The subagent prompt MUST include:

1. The pass name and its position number
2. The synthesized diagnosis — both the review findings and the failure analysis
3. Instructions: Fix the test failures in the Rust port. Do NOT re-port from scratch. Use the diagnosis to guide fixes. After fixing, run bash compiler/scripts/test-rust-port.sh <PassName> to verify. Repeat until 0 failures or you've made 3 fix attempts without progress.
4. Architecture guide path: compiler/docs/rust-port/rust-port-architecture.md
5. Pipeline path: compiler/crates/react_compiler/src/entrypoint/pipeline.rs

After the fix subagent completes:

1. Re-run bash compiler/scripts/test-rust-port.sh --json 2>/dev/null to get updated counts and frontier
2. If still failing, repeat the parallel diagnosis + fix cycle (max 3 rounds total)
3. Once clean (or after 3 rounds), update the orchestrator log Status section and add a log entry
4. Go to Step 4 (Review and Commit)

3b. PORT mode (frontier is the next unported pass)

Handle special cases first:

• Second PruneMaybeThrows call (#15): Launch a general-purpose subagent to add a second call to prune_maybe_throws + log_debug! in pipeline.rs, then run tests.
• outlineJSX (between #20 and #21): Conditional on enableJsxOutlining. Has no log entry. Launch a subagent to handle inline or via the compiler-port pattern.
• Conditional passes (#3, #13, #19, #21, #22): Note the condition when delegating.

For standard passes, launch a single general-purpose subagent with these instructions:

1. Pass name: <PassName> (position #N in the pipeline)
2. Instructions: Port the <PassName> pass from TypeScript to Rust. Follow these steps: a. Read the architecture guide at compiler/docs/rust-port/rust-port-architecture.md b. Read the pass documentation in compiler/packages/babel-plugin-react-compiler/docs/passes/ c. Find the TypeScript source by following the import in compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Pipeline.ts d. Read the Rust pipeline at compiler/crates/react_compiler/src/entrypoint/pipeline.rs and existing crate structure e. Port the pass, create/update crates as needed, wire into pipeline.rs f. Run bash compiler/scripts/test-rust-port.sh <PassName> and fix failures in a loop until 0 failures (max 5 attempts) g. Report: files created/modified, final test count, any remaining issues
3. Special notes (if any — e.g., conditional gating, reuse of existing functions)

After the subagent completes:

1. Re-run bash compiler/scripts/test-rust-port.sh --json 2>/dev/null to get updated counts and frontier
2. Update the orchestrator log Status section and add a log entry
3. Go to Step 4 (Review and Commit)

Step 4: Review and Commit

Use /compiler-commit <title> to review, verify, and commit the changes. This skill:

1. Runs /compiler-verify (tests, lint, format)
2. Runs /compiler-review on uncommitted changes — stops if issues are found
3. Updates the orchestrator log with test results
4. Commits with the correct [rust-compiler] prefix

Choose a descriptive commit title based on what the subagent did (e.g., "Port AnalyseFunctions pass" or "Fix SSA phi node ordering").

After committing:

1. Parse the commit hash from the output
2. Add a log entry noting the commit
3. Work continues — commits are checkpoints, not stopping points

Step 5: Loop

Go back to Step 1. The loop continues until:

• All passes are ported and clean (up to #49)
• An unrecoverable error occurs

Key Principles

1. Earliest failure wins: Even a single test failure in pass #2 must be fixed before working on pass #11. Early errors cascade — a bug in lowering can cause false failures in every downstream pass.

2. Cumulative testing: test-rust-port.sh <PassName> tests ALL passes up to and including the named pass. A clean result for the last pass implies all earlier passes are clean too.

3. Incremental commits: Commit after each meaningful unit of progress. Don't batch multiple passes into one commit. Each commit should leave the tree in a clean state.

4. Delegate everything: The main context MUST NOT read source code, investigate bugs, or make edits. It only: parses subagent results, updates the orchestrator log, prints status, and launches the next subagent. All code reading, debugging, fixing, porting, reviewing, and committing happens in subagents.

Source: facebook/react — distributed by TomeVault.