Slack API breaking changes (2025–2026): complete tracker and fixes
slack 17 breaking / deprecation entries 2025–2026
Slack ships API and SDK changes continuously. Most are additive — but the ones that are not can silently break integrations that worked yesterday. This page is the complete, continuously regenerated record of every Slack breaking change and deprecation in the mendapi change database: 17 entries (16 breaking, 1 deprecation), each linked to its upstream source and, where possible, to a concrete fix.
How to read this page
Every entry carries a fixability verdict from the mendapi adjudication pipeline: code-fixable means a mechanical code change repairs the break (4 entries); not code-fixable means the change requires a business decision, credential provisioning, or upstream action that no codemod can produce (13 entries). Entries marked auto-fix pack have a deterministic, gold-tested migration pack that mendapi fix can apply locally.
Am I affected?
Reading a changelog tells you what changed — not whether your code uses the affected surface. The mendapi scanner answers that locally, in about 30 seconds, without any code leaving your machine:
npx mendapi scan # -> N findings: file, line, provider, confidence mendapi deps --match # -> which of the changes below actually hit your endpoints
See Getting Started for the full workflow and the security model for why zero code upload is the default and only mode.
Complete Slack breaking change timeline
| Date | Change | Ref |
|---|---|---|
| 2026-07-14 | @slack/[email protected] breaking not code-fixable |
source |
| 2026-07-14 | @slack/[email protected] breaking not code-fixable |
source |
| 2026-07-14 | @slack/[email protected] breaking not code-fixable |
source |
| 2026-07-14 | @slack/[email protected] breaking not code-fixable |
source |
| 2026-07-14 | @slack/[email protected] breaking code-fixable auto-fix pack |
source |
| 2026-07-14 | @slack/[email protected] breaking not code-fixable |
source |
| 2026-07-14 | @slack/[email protected] breaking code-fixable auto-fix pack |
source |
| 2026-07-14 | @slack/[email protected] breaking code-fixable auto-fix pack |
source |
| 2025-08-28 | New feature: We improved our SDKs and tools breaking not code-fixable |
source |
| 2025-08-28 | New feature: An update to api.slack.com's docs breaking not code-fixable |
source |
| 2025-07-31 | New feature: We improved our SDKs and tools breaking not code-fixable |
source |
| 2025-07-21 | New feature: An update about an API or feature breaking not code-fixable |
source |
| 2025-06-19 | New feature: We improved our SDKs and tools breaking not code-fixable |
source |
| 2025-05-08 | New feature: We improved our SDKs and tools breaking not code-fixable |
source |
| 2025-03-27 | New feature: An update to api.slack.com's docs deprecation not code-fixable |
source |
| 2025-02-27 | New feature: An update to the Slack CLI breaking not code-fixable |
source |
| 2025-02-27 | New feature: An update to the Slack CLI breaking code-fixable auto-fix pack |
source |
Automated migration packs for Slack
mendapi ships 2 deterministic migration packs for Slack — verified, idempotent codemods you can apply locally with mendapi fix. Full details in the pack catalog.
slack-cli-hooks-file-move— Slack CLI 3.0.0: slack.json relocated to .slack/hooks.json (project config move) (upstream reference)slack-sdk-v8-errors— Slack SDK v8 error-handling migration (ErrorCode checks -> instanceof) (upstream reference)
Monitoring Slack going forward
This page is regenerated from the change database, which is fed by release feeds, changelog capture and OpenAPI spec diffing — so it does not depend on Slack writing a perfect changelog. mendapi monitors 53543 change records across 20 providers; hosted plans watch your repos continuously and open fix PRs when a change lands. See pricing.
Related
- All breaking-change reports — per-change deep dives with migration guides.
- All monitored providers — live change counts.
- Migration pack catalog — every deterministic fix mendapi ships.