Use canonical no-op span context for Expo compatibility

.changeset/sour-trees-smile.md

@@ -0,0 +1,5 @@
+---
+'@livestore/utils': patch
+---
+
+Use OpenTelemetry's canonical invalid span context for no-op spans, avoiding a platform-specific ID generator that Metro could not resolve through a package self-import.

CHANGELOG.md

@@ -513,6 +513,7 @@ See the [S2 sync provider docs](https://dev.docs.livestore.dev/reference/syncing
 #### Development Tooling
 
 - **Effect v4 dependency cohort:** Updated the repository-wide Effect v4 dependency family to beta.99 and migrated graph access to the public API while preserving degree-local history traversal ([#1446](https://github.com/livestorejs/livestore/issues/1446)).
+- **Expo source-linked tracing:** No-op spans now use OpenTelemetry's canonical invalid span context, so Metro can bundle workspace source without a platform-specific ID generator ([#1450](https://github.com/livestorejs/livestore/issues/1450)).
 - **Strict peer dep composition:** Added `@effect/vitest` to `utilsEffectPeerDeps` and `@livestore/peer-deps`, and deduplicated the peer-deps package to derive its dependency list from the canonical `utilsEffectPeerDeps` source ([#1107](https://github.com/livestorejs/livestore/issues/1107)).
 - **Hosted example link validation:** Maintainers now have a shared deployment metadata source and `mono examples validate-links` check so docs and example deployments can catch stale first-party demo URLs before publishing ([#1244](https://github.com/livestorejs/livestore/issues/1244)).
 - **Chrome DevTools extension assets restored:** Restored `qrcode-generator` 2.0.4 in `@livestore/utils` and included the Chrome DevTools extension assets in the release artifact flow so the published DevTools package contains the Chrome extension build alongside the Vite plugin ([#1215](https://github.com/livestorejs/livestore/pull/1215)).

context/02-system/06-observability/requirements.md

@@ -18,8 +18,8 @@ this node owns tracing/telemetry semantics.
   traces.
 - **LS.SYS.OBS-R02 No-op default:** Without an app-provided tracer,
   instrumentation degrades to a built-in no-op tracer: no exporter, no
-  network, bounded per-span overhead (today: one object allocation plus
-  start/end timestamps — a stricter zero-allocation budget is open, see
+  network, bounded per-span overhead (today: one object allocation and a
+  shared invalid OpenTelemetry span context — a stricter zero-allocation budget is open, see
   LS.SYS.OBS-DQ3). `refines: LS-R14`
 - **LS.SYS.OBS-R03 Injectable tracer:** Apps provide their tracer/exporter;
   LiveStore never configures a global exporter on its own.

context/02-system/06-observability/spec.md

@@ -18,8 +18,7 @@ Draft.
   (LS.SYS.OBS-R03).
 - `utils/src/NoopTracer.ts` is the default when no tracer is provided
   (LS.SYS.OBS-R02). It is cheap but not free: each span allocates a span
-  object and reads `performance.now()` at start and end (plus two `cuid()`
-  calls if `spanContext()` is consulted). A zero-allocation no-op path on
+  object and returns OpenTelemetry's shared invalid span context. A zero-allocation no-op path on
   the synchronous read path is an aspiration, not current behavior
   (LS.SYS.OBS-DQ3).
 - Dev-tracing recipe: `@livestore/utils-dev` `OtelLiveHttp` wires OTLP HTTP
@@ -76,8 +75,8 @@ linkage today. Convergence is an open direction.
 - **LS.SYS.OBS-DQ2 Metrics contract.** No metrics are emitted today; whether
   LiveStore should expose counters/histograms (commit rate, rebase count,
   query latency) is undesigned.
-- **LS.SYS.OBS-DQ3 No-op overhead budget.** The NoopTracer allocates and
-  reads clocks per span on hot paths (issue #1420); whether a
+- **LS.SYS.OBS-DQ3 No-op overhead budget.** The NoopTracer allocates one
+  object per span on hot paths (issue #1420); whether a
   zero-allocation budget should be contracted (and how to verify it) is
   open. Kept deliberately open 2026-07-16 (interview).
 

packages/@livestore/utils/src/NoopTracer.test.ts

@@ -0,0 +1,20 @@
+import { INVALID_SPAN_CONTEXT, isSpanContextValid, ROOT_CONTEXT } from '@opentelemetry/api'
+import { describe, expect, it } from 'vitest'
+
+import { makeNoopSpan, makeNoopTracer } from './NoopTracer.ts'
+
+describe('NoopTracer', () => {
+  it('returns the canonical invalid OpenTelemetry span context', () => {
+    const spanContext = makeNoopSpan().spanContext()
+
+    expect(spanContext).toBe(INVALID_SPAN_CONTEXT)
+    expect(isSpanContextValid(spanContext)).toBe(false)
+  })
+
+  it('runs active-span callbacks for every tracer overload', () => {
+    const tracer = makeNoopTracer()
+    expect(tracer.startActiveSpan('two arguments', () => 'two')).toBe('two')
+    expect(tracer.startActiveSpan('three arguments', {}, () => 'three')).toBe('three')
+    expect(tracer.startActiveSpan('four arguments', {}, ROOT_CONTEXT, () => 'four')).toBe('four')
+  })
+})

packages/@livestore/utils/src/NoopTracer.ts

@@ -1,6 +1,4 @@
-import type * as otel from '@opentelemetry/api'
-
-import { cuid } from '@livestore/utils/cuid'
+import { INVALID_SPAN_CONTEXT, type Context, type Span, type SpanOptions, type Tracer } from '@opentelemetry/api'
 
 export const makeNoopSpan = () => {
   const spanImpl = {
@@ -12,46 +10,37 @@ export const makeNoopSpan = () => {
     updateName: () => null,
     recordException: () => null,
     end: () => null,
-    spanContext: () => {
-      return {
-        traceId: `livestore-noop-trace-id${cuid()}`,
-        spanId: `livestore-noop-span-id${cuid()}`,
-      }
-    },
+    spanContext: () => INVALID_SPAN_CONTEXT,
   }
 
   // oxlint-disable-next-line typescript-eslint(no-unsafe-type-assertion) -- noop otel.Span implementation; only implements the subset needed by LiveStore
-  return spanImpl as unknown as otel.Span
+  return spanImpl as unknown as Span
 }
 
 export const makeNoopTracer = () => {
   // oxlint-disable-next-line typescript-eslint(no-unsafe-type-assertion) -- noop otel.Tracer implementation; only implements the subset needed by LiveStore
-  return new NoopTracer() as unknown as otel.Tracer
+  return new NoopTracer() as unknown as Tracer
 }
 
 export class NoopTracer {
   startSpan = () => makeNoopSpan()
 
-  startActiveSpan<F extends (span: otel.Span) => ReturnType<F>>(name: string, fn: F): ReturnType<F>
-  startActiveSpan<F extends (span: otel.Span) => ReturnType<F>>(
-    name: string,
-    opts: otel.SpanOptions,
-    fn: F,
-  ): ReturnType<F>
-  startActiveSpan<F extends (span: otel.Span) => ReturnType<F>>(
+  startActiveSpan<F extends (span: Span) => ReturnType<F>>(name: string, fn: F): ReturnType<F>
+  startActiveSpan<F extends (span: Span) => ReturnType<F>>(name: string, opts: SpanOptions, fn: F): ReturnType<F>
+  startActiveSpan<F extends (span: Span) => ReturnType<F>>(
     name: string,
-    opts: otel.SpanOptions,
-    ctx: otel.Context,
+    opts: SpanOptions,
+    ctx: Context,
     fn: F,
   ): ReturnType<F>
-  startActiveSpan<F extends (span: otel.Span) => ReturnType<F>>(
+  startActiveSpan<F extends (span: Span) => ReturnType<F>>(
     _name: string,
-    arg2?: F | otel.SpanOptions,
-    arg3?: F | otel.Context,
+    arg2?: F | SpanOptions,
+    arg3?: F | Context,
     arg4?: F,
   ): ReturnType<F> | undefined {
-    let _opts: otel.SpanOptions | undefined
-    let _ctx: otel.Context | undefined
+    let _opts: SpanOptions | undefined
+    let _ctx: Context | undefined
     let fn: F
 
     if (arguments.length < 2) {
@@ -61,14 +50,14 @@ export class NoopTracer {
       fn = arg2 as F
     } else if (arguments.length === 3) {
       // oxlint-disable-next-line typescript-eslint(no-unsafe-type-assertion) -- arguments-based overload dispatch: with 3 args, arg2 is SpanOptions
-      _opts = arg2 as otel.SpanOptions | undefined
+      _opts = arg2 as SpanOptions | undefined
       // oxlint-disable-next-line typescript-eslint(no-unsafe-type-assertion) -- arguments-based overload dispatch: with 3 args, arg3 is the callback
       fn = arg3 as F
     } else {
       // oxlint-disable-next-line typescript-eslint(no-unsafe-type-assertion) -- arguments-based overload dispatch: with 4 args, arg2 is SpanOptions
-      _opts = arg2 as otel.SpanOptions | undefined
+      _opts = arg2 as SpanOptions | undefined
       // oxlint-disable-next-line typescript-eslint(no-unsafe-type-assertion) -- arguments-based overload dispatch: with 4 args, arg3 is Context
-      _ctx = arg3 as otel.Context | undefined
+      _ctx = arg3 as Context | undefined
       // oxlint-disable-next-line typescript-eslint(no-unsafe-type-assertion) -- arguments-based overload dispatch: with 4 args, arg4 is the callback
       fn = arg4 as F
     }