Rspamd
Rspamd 4.3 fixes SPF evaluation order and rejects weak DKIM keys, with results that change.
Comparison · Collab
Slack vs SOGo
A side-by-side editorial comparison of Slack and SOGo — release velocity, themes, recent moves, and the top alternatives to consider.
Slack vs SOGo: at a glance
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.
What is SOGo?
SOGo's 5.12.13 fixes its largest batch of vulnerabilities yet, some critical.
SOGo, Alinto's self-hosted webmail, calendar and contacts suite, has made almost every 2026 release about security. v5.12.13 on 4 November fixes two SQL injections, a buffer overflow, an LDAP filter injection, path traversal, an impersonation flaw and several unsafe HTML elements, affecting all previous versions. It follows 5.12.11's password reset poisoning fix and 5.12.12's switch to verifying LDAP TLS certificates by default.
Slack vs SOGo: editorial side-by-side
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.
SOGo
5.0COLLAB
SOGo's 5.12.13 fixes its largest batch of vulnerabilities yet, some critical.
◆ Current state
SOGo, Alinto's self-hosted webmail, calendar and contacts suite, has made almost every 2026 release about security. v5.12.13 on 4 November fixes two SQL injections, a buffer overflow, an LDAP filter injection, path traversal, an impersonation flaw and several unsafe HTML elements, affecting all previous versions. It follows 5.12.11's password reset poisoning fix and 5.12.12's switch to verifying LDAP TLS certificates by default.
◆ Where it's heading
Outside researchers and coordinators such as VulnCheck are now reporting issues in batches, and each release closes several at once. The fixes are moving from individual XSS paths toward input handling across SQL, LDAP and file paths, which points to a broader audit of the codebase rather than one-off patches.
◆ Prediction
Expect CVE IDs for the 5.12.13 fixes to be published and further 5.12.x security releases at a roughly monthly pace; the entries show no sign of a feature release.
Slack alternatives
Other Collab products tracked by Sparkpulse, ranked by recent ship velocity. Tap any card for the full editorial trajectory or compare directly with 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.
SOGo alternatives
Other Collab products tracked by Sparkpulse, ranked by recent ship velocity. Tap any card for the full editorial trajectory or compare directly with SOGo.
Interact
Interact opens its intranet to outside AI assistants and uses Claude to attack its own platform.
Nextcloud
Nextcloud's November patches lean on preview speed and sharing fixes across three branches.
Mattermost
Mattermost v12.1 puts bots and burn-after-reading messages under the same access rules.
Asana
Asana lets Division admins run their own custom roles, on top Enterprise plans only.
Double
Double turns a recorded Chrome session into an agent that repeats the task.
SiYuan
SiYuan 3.8.11 alphas add freeform mind maps and plugin snapshots right after 3.8.10.
Recent activity from Slack and SOGo
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 agoSOGoSOGo 5.12.13 fixes SQL injections, overflow and impersonation
- 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 agoSOGoSOGo 5.12.12 fixes a vulnerability, enforces LDAP TLS checks
- 2mo agoSOGoSOGo 5.12.11: reset poisoning and XSS fixed, new required setting
- 3mo agoSOGoFour more vulnerabilities patched; all prior versions affected
- 5mo agoSOGoPatch undoes 5.12.8 regressions in preferences and mail display
- 6mo agoSOGoTwo CVEs fixed for PostgreSQL user sources
Frequently asked questions
What is the difference between Slack and SOGo?
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 Slack better than SOGo?
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 Collab products to evaluate alongside.
What are the best alternatives to Slack?
Top Slack alternatives in Collab 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.
What are the best alternatives to SOGo?
Top SOGo alternatives in Collab are ranked by recent ship velocity. Browse the "SOGo alternatives" section above for the current picks, or visit /alternatives/sogo for the full list with editorial commentary on each.