Rspamd
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Comparison · Comms
Threema vs Slack
A side-by-side editorial comparison of Threema and Slack — release velocity, themes, recent moves, and the top alternatives to consider.
Threema vs Slack: at a glance
What is Threema?
Threema's feed stays with security commentary as shipping news remains scarce
The feed continues to carry essays more often than releases. The newest entry is a commentary on recent cyberattacks in Switzerland, Denmark and France, following the August DDoS incident post and position pieces on interoperability and anonymity. The last concrete product item in view remains the Threema Work tag management update from July.
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.
Threema vs Slack: editorial side-by-side
Threema
2.5COMMS
Threema's feed stays with security commentary as shipping news remains scarce
◆ Current state
The feed continues to carry essays more often than releases. The newest entry is a commentary on recent cyberattacks in Switzerland, Denmark and France, following the August DDoS incident post and position pieces on interoperability and anonymity. The last concrete product item in view remains the Threema Work tag management update from July.
◆ Where it's heading
Threema is still competing on stance rather than feature velocity, and external attacks give that stance a current news peg. Product news continues to surface mainly on the Threema Work administration side, and nothing since July's roadmap teaser shows those plans landing. This feed's silence may understate app development, which is not its focus.
◆ Prediction
Expect more privacy and security commentary, with any shipping news most likely an administration feature for Threema Work. The entries do not show when items from the July roadmap post will arrive.
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 Threema 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 Threema 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 Threema alternatives → · See all Slack alternatives →
Recent activity from Threema 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 agoThreemaWhen Systems Go Silent: Staying Connected During a Cyberattack
- 12d agoSlackUpdated low-usage submission criteria for Slack Marketplace apps
- 15d agoSlackSlack CLI 4.12.0, the fourth CLI release in October
- 26d agoThreemaWhat’s behind the current wave of cyberattacks?
- 3mo agoThreemaDDoS Attacks on Threema
- 3mo agoThreemaMessenger Interoperability: Well-Intended, but Bad for Data Privacy
- 3mo agoThreemaEasier Tag Management in the Management Cockpit
- 4mo agoThreemaWorld Emoji Day: Our Emoji Pet Peeves
Frequently asked questions
What is the difference between Threema and Slack?
They serve adjacent needs but don't currently overlap on shipped themes. Slack is currently shipping more aggressively (velocity 6.3 vs 2.5), 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 Threema 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 2.5), 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 Threema?
Top Threema alternatives in Comms are ranked by recent ship velocity. Browse the "Threema alternatives" section above for the current picks, or visit /alternatives/threema 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.