refactor(compiler): replace hardcoded registry with framework manifest

[viniciusdacal]

Summary

• Introduces ReactivityManifest type system for describing reactivity shapes of exports
• Creates packages/ui/reactivity.json — the framework manifest for @vertz/ui APIs (query, form, createLoader, useContext, signal)
• Creates reactivity-manifest.ts with loading utilities (JSON string[] → Set<string> conversion)
• Adds CompileOptions.manifests parameter to pass pre-loaded manifests through the compile pipeline
• Refactors buildImportAliasMap in ReactivityAnalyzer to consume manifests, with fallback to hardcoded registry

Closes #989

Key design decisions

• Backward compatible: All existing callers that don't provide manifests still work via the hardcoded registry fallback
• Manifest-first resolution: resolveSignalApiConfig() checks manifestConfigs before falling back to getSignalApiConfig()
• Loaded types: JSON manifests use string[] for properties; loaded manifests use Set<string> for O(1) lookups
• Version forward compatibility: Unsupported manifest versions fall back to treating all exports as unknown

Test plan

• 10 new manifest loading tests (version handling, Set conversion, framework manifest loading)
• 1 new integration test proving manifest overrides hardcoded registry (custom signal properties)
• All 436 ui-compiler tests pass (including all existing signal API tests — backward compat verified)
• Typecheck clean
• Lint/format clean
• 67 turborepo tasks pass

🤖 Generated with Claude Code

[viniciusdacal]

✅ Adversarial Review — josh (DX)

Design compliance: ✅

Matches Section 2.2.5 (framework manifest) and Section 2.3 (Layer 2a) exactly.

Technical review: ✅

Cross-checked:

1. Manifest vs registry parity — Verified every property in reactivity.json matches SIGNAL_API_REGISTRY:

   • query: signal=[data,loading,error,revalidating], plain=[refetch,revalidate,dispose] ✅
   • form: signal=[submitting,dirty,valid], plain=[action,method,onSubmit,reset,setFieldError,submit], field=[value,error,dirty,touched] ✅
   • createLoader: signal=[data,loading,error], plain=[refetch] ✅
   • useContext: reactive-source ✅
   • signal: added (not in old registry, additive only) ✅

2. Fallback path — When no manifests provided, buildImportAliasMap only processes @vertz/ui via hardcoded registry. All 425 existing tests pass without manifests. ✅

3. Override proof — Integration test uses custom manifest with customProp as signal property and data as plain. Proves manifest overrides registry (customProp.value appears, data.value does not). ✅

4. Set conversion — toSet() handles both Set<string> and string[] inputs via instanceof Set check. ✅

5. Version safety — Unsupported versions fall back to unknown for all exports. ✅

6. Type safety — LoadedReactivityManifest vs ReactivityManifest properly separates JSON (string[]) from runtime (Set). No any or as. ✅

7. Path resolution — resolve(__dirname, '../../ui/reactivity.json') works in monorepo structure. Cache prevents repeated I/O. ✅

Quality gates: ✅

• 436 tests pass, 67 turborepo tasks, typecheck + lint clean

Verdict: APPROVE — ready to merge.

[viniciusdacal]

Adversarial Review — josh (DX lead)

Verdict: REQUEST CHANGES

Summary

The manifest types, JSON file, loading utilities, and wiring through CompileOptions → ReactivityAnalyzer → buildImportAliasMap are well-structured. The reactivity.json matches SIGNAL_API_REGISTRY exactly. Tests pass. The integration test correctly proves manifest-driven compilation overrides the hardcoded registry.

However, there are issues ranging from "blocks ship" to "must address before next layer."

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Blocking Issues

1. Missing exports from public API — loadManifestFromJson and loadFrameworkManifest are unreachable

packages/ui-compiler/src/index.ts does not export loadManifestFromJson, loadFrameworkManifest, or any of the manifest types (ReactivityManifest, LoadedReactivityManifest, LoadedExportReactivityInfo, LoadedReactivityShape).

CompileOptions.manifests expects Record<string, LoadedReactivityManifest>, but no external consumer can construct a LoadedReactivityManifest because:

• loadManifestFromJson() is not exported
• loadFrameworkManifest() is not exported
• The LoadedReactivityManifest type itself is not exported (so consumers can't even type-annotate)

This means the manifests option on CompileOptions is publicly visible but practically unusable from @vertz/ui-server or any other consumer. The Bun plugin cannot wire the framework manifest without reaching into internals.

Fix: Export loadManifestFromJson, loadFrameworkManifest, and the manifest types from index.ts. These are the public API for Layer 2a.

2. Missing version warning — design doc requires it, code silently swallows it

Design doc Section 2.2.1:

When loading a manifest with an unknown version, the compiler falls back to treating all exports as unknown with a warning: [vertz:reactivity] Manifest version ${v} not supported (expected 1). Exports treated as unknown.

The code silently falls back to unknown with no console output. The test is named "warns and falls back to unknown" but only asserts the fallback, not the warning. This is a spec violation — a consumer shipping a v2 manifest against a v1 compiler would get silent degradation with no diagnostic trail.

Fix: Add console.warn(\[vertz:reactivity] Manifest version ${json.version} not supported (expected ${SUPPORTED_VERSION}). Exports treated as unknown.`)in the unsupported version branch. Update the test to assert the warning is emitted (e.g., spy onconsole.warn`).

3. loadFrameworkManifest is not wired into the compile pipeline — the registry is not replaced

The design doc Layer 2a (Section 2.3) says: "Replace hardcoded SIGNAL_API_REGISTRY with framework manifest." The PR title says "replace hardcoded registry with framework manifest." But in practice, the framework manifest is never loaded or passed to compile() automatically. loadFrameworkManifest() exists as a utility, but the Bun plugin (@vertz/ui-server) hasn't been updated and there's no auto-loading in compiler.ts.

The hardcoded SIGNAL_API_REGISTRY is still the only path used in production. The manifest system is tested in isolation but never activated. This means the PR title/description is misleading — this is "add manifest infrastructure alongside hardcoded registry," not "replace hardcoded registry."

Either:

• (a) Wire loadFrameworkManifest() into compile() as the default (when no manifests are provided, auto-load the framework manifest for @vertz/ui). This actually replaces the registry.
• (b) Or rename the PR to accurately reflect this is infrastructure-only, and create a follow-up issue to wire the framework manifest into the Bun plugin. But then Layer 2a is not done.

I'd prefer (a) — it's a few lines in compiler.ts and it completes the stated goal.

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Non-Blocking Issues (address before merge or as immediate follow-up)

4. Module-level cache with no invalidation for loadFrameworkManifest

The cachedFrameworkManifest is a module-level singleton with no reset mechanism. This makes testing harder and prevents cache invalidation if the manifest file changes during a long-running process. Consider exporting a _resetManifestCache() function (underscore-prefixed = test-only convention) or using a WeakRef-based approach.

Not blocking because the manifest is a static JSON file, but this will bite someone.

5. as LoadedReactivityShape cast in convertReactivityShape

Line 66 of reactivity-manifest.ts uses return shape as LoadedReactivityShape. The project convention discourages unnecessary as casts. Since non-signal-api shapes (static, signal, reactive-source, unknown) are structurally identical between ReactivityShape and LoadedReactivityShape, this could be replaced with explicit construction per variant:

if (shape.type === 'static') return { type: 'static' };
if (shape.type === 'signal') return { type: 'signal' };
if (shape.type === 'reactive-source') return { type: 'reactive-source' };
return { type: 'unknown' };

Verbose but cast-free and exhaustive.

6. resolveSignalApiConfig fallback is partially dead code when manifests are in play

In buildImportAliasMap, when a manifest is found for a module, only exports listed in the manifest are added to signalApiAliases. So resolveSignalApiConfig's fallback to getSignalApiConfig() is only reachable when no manifest is provided for @vertz/ui. This is semantically correct but creates a subtle coupling: the fallback looks like it could fire for manifest-classified imports, but it never will because the gating happens earlier. A comment clarifying this would help.

7. Design doc mentions reactiveProps?: string[] on ExportReactivityInfo — types omit it

The design doc defines reactiveProps?: string[] on ExportReactivityInfo (deferred, for component prop reactivity). The PR types omit it entirely. Since it's deferred, that's acceptable, but a // DEFERRED: reactiveProps?: string[] comment on the type would document the intent and prevent someone re-designing it.

What's Good

• reactivity.json is byte-for-byte faithful to SIGNAL_API_REGISTRY. No behavioral drift.
• The toSet() function correctly handles the "already a Set" case (idempotent loading).
• The integration test is the strongest part: it constructs a manifest with customProp as signal and data as plain (the opposite of the hardcoded registry), then verifies the compiler follows the manifest, not the registry. That proves override semantics.
• The fallback logic in buildImportAliasMap correctly preserves the hardcoded registry when no manifest is provided, so existing behavior is safe.
• __dirname resolution works from both src/ and dist/ since both are one level deep under packages/ui-compiler/.

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Verdict: REQUEST CHANGES — Issues #1 (missing exports), #2 (missing warning), and #3 (manifest not wired into pipeline) must be addressed. Issues #4-#7 can be follow-ups.