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+## Node-test workflow failure investigation
+
+- **Scope**: Release branch (all Node versions) – install step fails. Master passes.
+- **Reproduction environment**: linux x64; Node v22.16.0; npm 10.9.2.
+
+### Reproduction
+
+Command executed in repo root:
+
+```bash
+npm ci --foreground-scripts
+```
+
+Observed failure (excerpt):
+
+```
+> @sentry/cli@2.54.0 postinstall
+> node ./scripts/install.js
+
+[sentry-cli] Sentry CLI failed to locate the "@sentry/cli-linux-x64" package after installation!
+...
+[sentry-cli] Downloading from https://downloads.sentry-cdn.com/sentry-cli/2.54.0/sentry-cli-Linux-x86_64
+
+Error: Unable to download sentry-cli binary from https://downloads.sentry-cdn.com/sentry-cli/2.54.0/sentry-cli-Linux-x86_64.
+Server returned: 403 - Forbidden
+```
+
+Exit code: 1
+
+### Findings (evidence)
+
+- The JS package version in this branch is pinned to `2.54.0`:
+  - `package.json`:
+    - `version: 2.54.0`
+    - `optionalDependencies` include platform packages at `2.54.0` (e.g. `@sentry/cli-linux-x64: 2.54.0`).
+- The expected platform package for this environment is `@sentry/cli-linux-x64@2.54.0`.
+- Querying npm registry:
+
+```bash
+npm view @sentry/cli-linux-x64@2.54.0 version
+# => 404 No match found for version 2.54.0
+
+npm view @sentry/cli-linux-x64 versions --json | jq '.[-5:]'
+# Last published: ... "2.53.0" (no 2.54.0)
+```
+
+- CDN artifact URL check:
+
+```bash
+curl -sI https://downloads.sentry-cdn.com/sentry-cli/2.54.0/sentry-cli-Linux-x86_64
+# => HTTP/2 403
+```
+
+- Postinstall logic in `scripts/install.js` first resolves an optional dependency for the platform; when missing, it falls back to downloading from the CDN. Both paths fail here because:
+  - The platform package `@sentry/cli-linux-x64@2.54.0` is not published on npm.
+  - The CDN binary for 2.54.0 responds 403.
+
+### Root cause
+
+The release branch references a version `2.54.0` whose platform-specific binary distributions are not available:
+- Platform npm packages at `2.54.0` are missing.
+- Corresponding CDN artifacts for `2.54.0` return 403.
+
+As a result, `npm ci` fails during `postinstall` of `@sentry/cli` because neither the optional dependency install nor the CDN fallback can supply the binary.
+
+This explains why master passes (likely points to an available/published version) while this release branch fails (points to an unpublished/unavailable version).
+
+### Fix options
+
+- Update the version references in the release branch to a version whose platform packages and CDN artifacts exist (e.g. latest published series, such as `2.53.0` at the time of this investigation), keeping `optionalDependencies` in sync.
+- Alternatively, publish the missing platform packages (`@sentry/cli-<platform>@2.54.0`) and ensure the `2.54.0` binaries are available on the CDN, then re-run the workflow.
+- Temporary CI-only workaround (not recommended for releases): set `SENTRYCLI_SKIP_DOWNLOAD=1` and provide `SENTRY_BINARY_PATH` to a known-good binary, bypassing network download. This should only be used if binary provenance and licensing are handled.
+
+### Recommendation
+
+Prefer aligning the release branch to the latest fully published version (npm + CDN). If `2.54.0` is the intended release, publish all platform packages and make the CDN artifacts available before retrying CI.
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