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Comparison · Comms
Matrix vs Slack
A side-by-side editorial comparison of Matrix and Slack — release velocity, themes, recent moves, and the top alternatives to consider.
Matrix vs Slack: at a glance
What is Matrix?
Matrix 2.0 is down to its last few proposals as a German defence homeserver goes public
The Matrix spec process is closing out Matrix 2.0: after eight proposals were accepted on 30 October, the 6 November update counts two or three still open, including a small LiveKit follow-up that lets non-call apps use MatrixRTC channels. The same update brings Arminius, an enterprise homeserver Famedly built with Germany's BWI and has now published, though it is not ready for use. The Governing Board met for the second time this year and filled a vacated seat.
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.
Matrix vs Slack: editorial side-by-side
Matrix
5.0COMMS
Matrix 2.0 is down to its last few proposals as a German defence homeserver goes public
◆ Current state
The Matrix spec process is closing out Matrix 2.0: after eight proposals were accepted on 30 October, the 6 November update counts two or three still open, including a small LiveKit follow-up that lets non-call apps use MatrixRTC channels. The same update brings Arminius, an enterprise homeserver Famedly built with Germany's BWI and has now published, though it is not ready for use. The Governing Board met for the second time this year and filled a vacated seat.
◆ Where it's heading
Spec work is shifting from accepting the Matrix 2.0 set to clearing the queue behind it, and six new proposals in one week, from shared encrypted search to soundboards for calls, show where the next round is heading. Public-sector demand is now producing its own server implementations rather than only conference talks.
◆ Prediction
The remaining Matrix 2.0 proposals, starting with the LiveKit follow-up the spec team calls non-controversial, are likely to be accepted in the next few weekly updates, followed by an announcement that Matrix 2.0 is complete.
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 Matrix 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 Matrix 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 Matrix alternatives → · See all Slack alternatives →
Recent activity from Matrix and Slack
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 4d agoSlackBring your A2A agents to Slack ⚡
- 7d agoMatrixMatrix 2.0 nears the finish; BWI's Arminius homeserver goes public
- 8d agoSlackWork Objects embeds require the slack-mcps.com frame ancestor
- 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
- 12d agoSlackUpdated low-usage submission criteria for Slack Marketplace apps
- 14d agoMatrixMatrixRTC and sliding sync MSCs accepted ahead of Matrix 2.0
- 14d agoMatrixThe Matrix Conference 2026: Our biggest edition yet
- 14d agoMatrixCall for Participation - FOSDEM 2027 Decentralised Messaging Devroom
- 15d agoSlackSlack CLI 4.12.0, the fourth CLI release in October
- 21d agoMatrixThis Week in Matrix 2026-10-23
- 28d agoMatrixThis Week in Matrix 2026-10-16
Frequently asked questions
What is the difference between Matrix and Slack?
They serve adjacent needs but don't currently overlap on shipped themes. Slack is currently shipping more aggressively (velocity 6.3 vs 5.0), with 1 editorial sparks in the last 30 days against 0. See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Is Matrix better than Slack?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Slack is currently shipping more aggressively (velocity 6.3 vs 5.0), with 1 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Comms products to evaluate alongside.
What are the best alternatives to Matrix?
Top Matrix alternatives in Comms are ranked by recent ship velocity. Browse the "Matrix alternatives" section above for the current picks, or visit /alternatives/matrix 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.