Rspamd
Rspamd 4.3 fixes SPF evaluation order and rejects weak DKIM keys, with results that change.
Comparison · Comms
Grain vs Slack
A side-by-side editorial comparison of Grain and Slack — release velocity, themes, recent moves, and the top alternatives to consider.
Grain vs Slack: at a glance
| Feature | Grain | Slack |
|---|---|---|
| Sector | Comms | Comms, Collab |
| Velocity score | 2.5 | 6.3 |
| Sparks · 30d | 0 | 1 |
| Top themes | meeting-recording, privacy-controls, speaker-identification, mcp-tools | agents, a2a, mcp, slackbot-skills |
| Last editorial update | 11d ago | 3d ago |
| Website | — | Visit → |
What is Grain?
Grain adds consent controls and rule-based privacy as its meeting data reaches more AI tools.
Grain's October release lets workspaces flag meetings as sensitive by rule and skip auto-sharing them, adds recording consent controls, and brings back a mobile beta. It follows August's Voice Signatures, which label speakers by voice so shared-mic and in-person captures attribute correctly. Earlier in the year Grain shipped an MCP server and a ChatGPT integration.
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.
Grain vs Slack: editorial side-by-side
Grain
2.5COMMS
Grain adds consent controls and rule-based privacy as its meeting data reaches more AI tools.
◆ Current state
Grain's October release lets workspaces flag meetings as sensitive by rule and skip auto-sharing them, adds recording consent controls, and brings back a mobile beta. It follows August's Voice Signatures, which label speakers by voice so shared-mic and in-person captures attribute correctly. Earlier in the year Grain shipped an MCP server and a ChatGPT integration.
◆ Where it's heading
Grain spent the first half of 2026 exposing meeting data to AI assistants, and is now adding the governance that wider exposure needs: consent, sensitivity rules and controlled sharing. Release cadence has slowed to roughly one announcement every month or two.
◆ Prediction
Further admin and privacy controls around what AI tools can read are the likely next step; the entries do not show a timeline for the mobile app leaving beta.
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 Grain 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 Grain 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.
Recent activity from Grain 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
- 1mo agoGrainWorkspace Libraries, Recording Consent + Mobile Beta
- 2mo agoGrainVoice Signatures label who spoke, plus better transcription
- 4mo agoGrainGrain in ChatGPT + Smarter Notes and MCP Tools ⚡
- 5mo agoGrainOpt-in meeting notifications, better playlists, and more!
- 6mo agoGrainGrain MCP + Bulk AI Actions and API Updates ⚡
- 7mo agoGrainNew Home Page + Improved Zapier Integration
Frequently asked questions
What is the difference between Grain 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 Grain 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 Grain?
Top Grain alternatives in Comms are ranked by recent ship velocity. Browse the "Grain alternatives" section above for the current picks, or visit /alternatives/grain 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.