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Comparison · Comms
SimpleX Chat vs Slack
A side-by-side editorial comparison of SimpleX Chat and Slack — release velocity, themes, recent moves, and the top alternatives to consider.
SimpleX Chat vs Slack: at a glance
What is SimpleX Chat?
The no-identifier messenger is building public channels — and has to invent trust from scratch
SimpleX Chat is deep in a v7.0 beta cycle, six betas in, with the stable armv7a tag now cut. The release is dominated by channels: broadcast surfaces with subscribers, contributor and moderator roles, searchable subscriber lists, and CLI access. Alongside them sits SimpleX names — registerable, resolvable names for channels and businesses — and per-server role controls that let self-hosters run a relay that handles only message reception, private routing, or name resolution.
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.
SimpleX Chat vs Slack: editorial side-by-side
SimpleX Chat
6.3COMMS
The no-identifier messenger is building public channels — and has to invent trust from scratch
◆ Current state
SimpleX Chat is deep in a v7.0 beta cycle, six betas in, with the stable armv7a tag now cut. The release is dominated by channels: broadcast surfaces with subscribers, contributor and moderator roles, searchable subscriber lists, and CLI access. Alongside them sits SimpleX names — registerable, resolvable names for channels and businesses — and per-server role controls that let self-hosters run a relay that handles only message reception, private routing, or name resolution.
◆ Where it's heading
This is the hardest problem the project has taken on. SimpleX's premise is that users have no identifiers at all, and public channels need exactly the opposite: a stable name people can find and an author they can verify. The answer taking shape is cryptographic rather than account-based — message signing, member security-code verification, and name resolution run as an opt-in server function. The betas since then have shifted from adding channel features to hardening the role model, rejecting forwards from unexpected admins and locking relay-role assignment.
◆ Prediction
A 7.0 stable release looks imminent given the non-beta tag, with message signing held back for 7.1 as the notes state. Expect the next cycle to turn signing on and continue tightening who can act as a relay or admin inside a channel.
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 SimpleX 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 SimpleX 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 SimpleX Chat alternatives → · See all Slack alternatives →
Recent activity from SimpleX Chat and Slack
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 4d agoSlackBring your A2A agents to Slack ⚡
- 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
- 15d agoSlackSlack CLI 4.12.0, the fourth CLI release in October
- 3mo agoSimpleX Chatv7.0.0-beta.6
- 3mo agoSimpleX Chatv7.0.0-beta.5
- 3mo agoSimpleX Chatv7.0.0-beta.4 ⚡
- 4mo agoSimpleX Chatv7.0 beta 3: registrable SimpleX names for channels
- 4mo agoSimpleX ChatSimpleX 7.0-beta.2: subscriber roles and CLI channel connect
- 4mo agoSimpleX ChatPromote channel subscribers to contributors (v7.0 beta.1)
Frequently asked questions
What is the difference between SimpleX Chat and Slack?
They serve adjacent needs but don't currently overlap on shipped themes. SimpleX 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 SimpleX Chat better than Slack?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. SimpleX 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 SimpleX Chat?
Top SimpleX Chat alternatives in Comms are ranked by recent ship velocity. Browse the "SimpleX Chat alternatives" section above for the current picks, or visit /alternatives/simplex-chat 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.