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Comparison · Comms
Rocket.Chat vs Slack
A side-by-side editorial comparison of Rocket.Chat and Slack — release velocity, themes, recent moves, and the top alternatives to consider.
Rocket.Chat vs Slack: at a glance
What is Rocket.Chat?
Rocket.Chat 9.0 reaches rc.8 with a migration fix as candidates shrink to single patches.
The 9.0 candidate line opened on 27 October with a licensing change: LDAP, SAML and Custom OAuth now require a premium plan. Since rc.4 the candidates have been fixes, and rc.8 on 7 November carries a single one: servers that started during another server's database migration no longer keep stale settings until restart. On 6 November 8.9.1 LTS backported the 9.0 load fixes plus a security hotfix.
What is Slack?
Slack now hosts any A2A agent without Slack-specific code.
Slack's developer channel is almost all agent plumbing. On 10 November Slack became an A2A (Agent2Agent) client: a team hosts its own agent, publishes an Agent Card, and Slack calls it when people talk to it, with no request URL, event handling or Slack-specific logic. This follows Slackbot skills managed through Web API methods, a Slack CLI that points coding agents to the Slack MCP server, and a new requirement that Work Objects embeds allow the slack-mcps.com frame ancestor.
Rocket.Chat vs Slack: editorial side-by-side
Rocket.Chat
6.3COMMS
Rocket.Chat 9.0 reaches rc.8 with a migration fix as candidates shrink to single patches.
◆ Current state
The 9.0 candidate line opened on 27 October with a licensing change: LDAP, SAML and Custom OAuth now require a premium plan. Since rc.4 the candidates have been fixes, and rc.8 on 7 November carries a single one: servers that started during another server's database migration no longer keep stale settings until restart. On 6 November 8.9.1 LTS backported the 9.0 load fixes plus a security hotfix.
◆ Where it's heading
9.0 is in stabilization: each candidate is smaller than the last, and the load fixes are being carried to the LTS line rather than held for the major. Native LiveKit video is being promoted step by step, from alpha to beta and now as the named default provider option.
◆ Prediction
With rc.7 down to a handful of fixes, 9.0.0 GA is the next likely release, followed by further 8.9.x LTS patches carrying the same fixes.
Slack
6.3COMMSCOLLAB
Slack now hosts any A2A agent without Slack-specific code.
◆ Current state
Slack's developer channel is almost all agent plumbing. On 10 November Slack became an A2A (Agent2Agent) client: a team hosts its own agent, publishes an Agent Card, and Slack calls it when people talk to it, with no request URL, event handling or Slack-specific logic. This follows Slackbot skills managed through Web API methods, a Slack CLI that points coding agents to the Slack MCP server, and a new requirement that Work Objects embeds allow the slack-mcps.com frame ancestor.
◆ Where it's heading
Slack is lowering the cost of putting outside agents in front of its users: first skills as code, then MCP pointers for coding agents, now a standard protocol in place of the Slack app model for agents. The platform is positioning itself as the place where agents built anywhere meet the people who use them.
◆ Prediction
Expect more A2A follow-ups, such as agents appearing in Slackbot or skills surfaces and richer Agent Card features, given how fast the agent releases have stacked up since October.
Alternatives to Rocket.Chat and Slack
Other Comms products tracked by Sparkpulse, ranked by recent ship velocity. Each card links to a full editorial trajectory and lets you pivot into a head-to-head comparison with either Rocket.Chat or Slack.
Twilio
Twilio's voice AI stops cutting callers off mid-sentence, using its own turn-taking model.
Salesmsg
Salesmsg adds call-back requests and a one-click Emergency Stop for all outbound texts.
Element
Element 1.12.35 follows the call picture-in-picture release with one desktop storage fix.
Krisp
Krisp moves call transcripts and live captions to cloud transcription in KrispCX 2.84.4.
Misskey
Misskey 2026.11 ships: a leaner start script, and Node.js 22 no longer boots.
See all Rocket.Chat alternatives → · See all Slack alternatives →
Recent activity from Rocket.Chat and Slack
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 4d agoSlackBring your A2A agents to Slack ⚡
- 7d agoRocket.Chat9.0 rc.8: settings refresh after concurrent migrations
- 8d agoRocket.Chat8.9.1 LTS: load fixes from 9.0 plus a security hotfix
- 8d agoSlackWork Objects embeds require the slack-mcps.com frame ancestor
- 8d agoRocket.Chat9.0 rc.7: client memory leak fixed, LiveKit video moves to beta
- 9d agoRocket.Chat9.0 rc.6: Matrix federation auth header fix
- 9d agoRocket.Chat9.0 rc.5: removed-license features shut off, OAuth codes redacted
- 10d agoSlackSlack CLI 4.13 tells coding agents about Slack MCP and Skills
- 10d agoSlackSlack Skills Plugin installs in Claude Code from its own marketplace
- 10d agoRocket.Chat9.0 rc.4: notifications, presence and startup fixed under load
- 12d agoSlackUpdated low-usage submission criteria for Slack Marketplace apps
- 15d agoSlackSlack CLI 4.12.0, the fourth CLI release in October
Frequently asked questions
What is the difference between Rocket.Chat and Slack?
They serve adjacent needs but don't currently overlap on shipped themes. Rocket.Chat and Slack are shipping at a similar cadence (velocity 6.3 vs 6.3, both within Sparkpulse's "active" band). See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Is Rocket.Chat better than Slack?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Rocket.Chat and Slack are shipping at a similar cadence (velocity 6.3 vs 6.3, both within Sparkpulse's "active" band). For your specific use case, the alternatives sections above list other Comms products to evaluate alongside.
What are the best alternatives to Rocket.Chat?
Top Rocket.Chat alternatives in Comms are ranked by recent ship velocity. Browse the "Rocket.Chat alternatives" section above for the current picks, or visit /alternatives/rocketchat for the full list with editorial commentary on each.
What are the best alternatives to Slack?
Top Slack alternatives in Comms are ranked by recent ship velocity. Browse the "Slack alternatives" section above for the current picks, or visit /alternatives/slack for the full list with editorial commentary on each.