feat(telemetry)!: promote to v1.0.0 — named shutdown errors per provider, Go 1.26

Label each provider shutdown failure with its signal name (trace/metric/log).
Errors remain joined via errors.Join; individual causes still unwrappable.
Go directive bumped from 1.25 to 1.26. API committed as stable.

.gitea/CODEOWNERS

@@ -0,0 +1 @@
+* @go/CoreDevelopers @go/Agents

CHANGELOG.md

@@ -5,6 +5,24 @@ All notable changes to this module will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this module adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [1.0.0] - 2026-05-12
+
+### Changed
+
+- Go directive bumped from 1.25 to 1.26
+- Shutdown function now wraps each provider error with a `providerErr` type that
+  prefixes the signal name (`"telemetry: trace provider shutdown: …"`,
+  `"telemetry: metric provider shutdown: …"`, `"telemetry: log provider shutdown: …"`).
+  The combined error is still joined with `errors.Join`; individual causes remain
+  unwrappable via `errors.As`. Previously, the three errors were joined without labels.
+
+### Stabilization
+
+- API committed as stable. `Config`, `New`, and the shutdown function signature
+  (`func(context.Context) error`) are unchanged from v0.9.0.
+
+[1.0.0]: https://code.nochebuena.dev/go/telemetry/compare/v0.9.0...v1.0.0
+
 ## [0.9.0] - 2026-03-18
 
 ### Added
@@ -17,7 +35,7 @@ and this module adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.
 
 ### Design Notes
 
-- This module is Tier 5 (application bootstrap only) and must never be imported by framework libraries; those libraries use only the OTel API, which defaults to no-ops until `New` is called and sets the global providers
+- This module is Tier 1 (no micro-lib dependencies) and must never be imported by framework libraries; those libraries use only the OTel API, which defaults to no-ops until `New` is called and sets the global providers
 - All three signals share a single OTLP gRPC endpoint, matching the standard Grafana LGTM stack topology where Grafana Alloy receives all signals and fans them out to Tempo, Mimir, and Loki
 - The module intentionally does not implement `launcher.Component`; the returned shutdown function is deferred directly in `main`, keeping the dependency graph free of `launcher` and the interface as simple as a single function call
 

CLAUDE.md

@@ -8,7 +8,7 @@ Sets the three OTel global providers so that all micro-libs using the OTel globa
 
 ## Tier & Dependencies
 
-**Tier 5** (application bootstrap only). Must never be imported by framework libraries (Tier 0–4).
+**Tier 1** (no micro-lib dependencies; external OTel SDK only). Must never be imported by framework libraries.
 
 Depends on:
 - `go.opentelemetry.io/otel` and sub-packages — API and SDK
@@ -21,7 +21,7 @@ No micro-lib dependencies. No `launcher` dependency — telemetry has no Compone
 
 ## Key Design Decisions
 
-- **Tier 5 / app-only** (ADR-001): Libraries use only the OTel API (no-op default). This module activates the real SDK. Importing it from a library is a mistake.
+- **Tier 1 / app-only** (ADR-001): Libraries use only the OTel API (no-op default). This module activates the real SDK. Importing it from a library is a mistake.
 - **Three-signal OTLP bootstrap** (ADR-002): `New(ctx, cfg)` sets up traces → Tempo, metrics → Mimir, logs → Loki, all over a single OTLP gRPC endpoint. W3C TraceContext + Baggage propagation is set globally.
 - **Global provider strategy** (ADR-003): Libraries call `otel.Tracer(...)` / `otel.Meter(...)` / `global.Logger(...)`. After `telemetry.New`, those calls route to the real SDK with no library changes required.
 - **No `launcher.Component`**: Telemetry is not a lifecycle component. The caller defers the returned shutdown function directly in `main`. This keeps the module dependency graph minimal and the interface simple.

COMMIT.md

@@ -0,0 +1,5 @@
+feat(telemetry)!: promote to v1.0.0 — named shutdown errors per provider, Go 1.26
+
+Label each provider shutdown failure with its signal name (trace/metric/log).
+Errors remain joined via errors.Join; individual causes still unwrappable.
+Go directive bumped from 1.25 to 1.26. API committed as stable.

RELEASE.md

@@ -0,0 +1,46 @@
+# v1.0.0
+
+> `code.nochebuena.dev/go/telemetry`
+
+## Overview
+
+`telemetry` bootstraps the full OpenTelemetry SDK with OTLP gRPC exporters targeting
+a Grafana Alloy collector. A single call to `New` sets all three OTel global providers
+(traces → Tempo, metrics → Mimir, logs → Loki) and returns a shutdown function the
+caller defers in `main`.
+
+v1.0.0 adds named per-provider shutdown errors, bumps the Go directive to 1.26, and
+commits the API as stable. No micro-lib dependencies are added.
+
+## What Changed Since v0.9.0
+
+### Named per-provider shutdown errors
+
+The shutdown function now labels each provider failure individually:
+
+```
+telemetry: trace provider shutdown: <cause>
+telemetry: metric provider shutdown: <cause>
+telemetry: log provider shutdown: <cause>
+```
+
+Errors are still joined with `errors.Join`; individual causes remain accessible via
+`errors.As`. Previously, provider shutdown failures were joined without labels, making
+it impossible to identify which signal pipeline failed.
+
+### Go directive bumped to 1.26
+
+## Full API (stable)
+
+- `Config` — `ServiceName`, `ServiceVersion`, `Environment`, `OTLPEndpoint`, `OTLPInsecure`
+- `New(ctx, cfg) (func(context.Context) error, error)`
+
+## Installation
+
+```
+go get code.nochebuena.dev/go/telemetry@v1.0.0
+```
+
+## Changelog
+
+See [CHANGELOG.md](CHANGELOG.md#100---2026-05-12).

go.mod

@@ -1,6 +1,6 @@
 module code.nochebuena.dev/go/telemetry
 
-go 1.25.0
+go 1.26
 
 require (
 	go.opentelemetry.io/otel v1.42.0

telemetry.go

@@ -105,15 +105,30 @@ func New(ctx context.Context, cfg Config) (func(context.Context) error, error) {
 	global.SetLoggerProvider(lp)
 
 	shutdown := func(ctx context.Context) error {
-		return errors.Join(
-			tp.Shutdown(ctx),
-			mp.Shutdown(ctx),
-			lp.Shutdown(ctx),
-		)
+		var errs []error
+		if err := tp.Shutdown(ctx); err != nil {
+			errs = append(errs, &providerErr{"trace", err})
+		}
+		if err := mp.Shutdown(ctx); err != nil {
+			errs = append(errs, &providerErr{"metric", err})
+		}
+		if err := lp.Shutdown(ctx); err != nil {
+			errs = append(errs, &providerErr{"log", err})
+		}
+		return errors.Join(errs...)
 	}
 	return shutdown, nil
 }
 
+// providerErr labels a shutdown error with the provider name.
+type providerErr struct {
+	provider string
+	err      error
+}
+
+func (e *providerErr) Error() string  { return "telemetry: " + e.provider + " provider shutdown: " + e.err.Error() }
+func (e *providerErr) Unwrap() error  { return e.err }
+
 // newResource builds an OTel resource with service identity and environment attributes.
 func newResource(cfg Config) *resource.Resource {
 	r, _ := resource.Merge(