---
package: "@opentelemetry/sdk-trace-base"
version: "^1.27.0"
tier: core
decision: approved
date: 2026-05-14
deciders: [Danijel Martinek]
adr: adr-017
filter-results:
  license: Apache-2.0
  types: native
  maintenance: active
  boundary-fit: pass
  shadow-check: pass
  eu-residency: n/a
  cve-scan: clean
  named-consumer: pass
verification-commands:
  - npm view @opentelemetry/sdk-trace-base license
  - npm view @opentelemetry/sdk-trace-base version
  - pnpm audit --audit-level=moderate
accepted-cves: []
---

## Filter: license

<!-- Result: Apache-2.0 -->

`npm view @opentelemetry/sdk-trace-base license` returns `Apache-2.0`. Apache-2.0 is on the allowlist.

## Filter: types

<!-- Result: native -->

`@opentelemetry/sdk-trace-base` is authored in TypeScript and ships its own `.d.ts` declaration files. No separate `@types/` package is needed.

## Filter: maintenance

<!-- Result: active -->

Actively maintained by the OpenTelemetry community on the stable 1.x track. The 1.27.x line is current; the tracing specification is stable within CNCF.

## Filter: boundary-fit

<!-- Result: pass -->

ADR-017 §8 restricts `@opentelemetry/sdk-trace-base` to `**/instrumentation/otel/**` and app init paths. `SpanProcessor` and `ReadableSpan` types from this package are used to implement `PiiScrubSpanProcessor` in `core-shared`. `packages/core-audit` also uses `ReadableSpan` for span context in audit records.

## Filter: shadow-check

<!-- Result: pass -->

`@opentelemetry/sdk-trace-base` is the OTel trace SDK foundation. No competing trace SDK is present in the workspace.

## Filter: eu-residency

<!-- Result: n/a -->

`@opentelemetry/sdk-trace-base` is the tracing SDK infrastructure with no independent data transmission. Spans are forwarded through configured processors and exporters. EU residency is governed by the exporter DSN configuration.

## Filter: cve-scan

<!-- Result: clean -->

`pnpm audit --audit-level=moderate` reports no advisories against `@opentelemetry/sdk-trace-base` at the time of this trace.

## Filter: named-consumer

<!-- Result: pass -->

`packages/core-shared/src/instrumentation/otel/pii-scrub-span-processor.ts` implements `SpanProcessor` from `@opentelemetry/sdk-trace-base` to scrub PII attributes before spans reach the Sentry exporter (ADR-017 §7). `packages/core-audit` uses `ReadableSpan` for audit record correlation.

## Prompt: replaces

The former `SentryTracer` which called Sentry SDK span methods directly. `@opentelemetry/sdk-trace-base` provides the `SpanProcessor` extension point that enables the `PiiScrubSpanProcessor` — a vendor-neutral, pre-export PII scrubbing layer.

## Prompt: migration-cost-out

Hard. `@opentelemetry/sdk-trace-base` types (`SpanProcessor`, `ReadableSpan`) are used in both `core-shared` PII scrub implementation and `core-audit`. Replacing it means adopting a different span processing abstraction and rewriting both the processor and audit span-context integration.

## Prompt: alternatives-considered

1. **Sentry `beforeSendTransaction` hook** — Sentry-native PII scrubbing hook. Rejected in ADR-017 §7: runs inside Sentry after OTel conversion; the OTel processor layer runs earlier and is vendor-agnostic, so any future exporter also sees clean data.
2. **No span processor, rely on Sentry scrubbing rules** — Rejected: Sentry-specific configuration; future exporter additions would need their own scrubbing configured separately.

See ADR-017 for the full decision rationale.
