Rspamd
Rspamd 4.3 fixes SPF evaluation order and rejects weak DKIM keys, with results that change.
Comparison · Comms
mailcow vs Session
A side-by-side editorial comparison of mailcow and Session — release velocity, themes, recent moves, and the top alternatives to consider.
mailcow vs Session: at a glance
What is mailcow?
mailcow's November release patches an admin RCE and reworks sync jobs.
mailcow ships named monthly releases with lettered revisions, mostly to pull in upstream security fixes for SOGo, Nginx, Redis, Unbound and Rspamd. The November release goes further: it fixes a remote code execution flaw reachable by admins and domain admins, adds mailbox groups, and reworks imapsync so sync jobs reference a separate source. It also caps request bodies at 64 MB, which breaks large SOGo and ActiveSync mail unless NGINX_MAX_BODY_SIZE is raised.
What is Session?
Session ships new app versions and node upgrades while Pro stays on hold.
Session's 2026 started with a funding scare, then community support restored its runway in June. Session Pro reached a beta in app stores in September before its launch was paused in October during talks with an allied privacy ecosystem. Since then the work is infrastructure: lighter Session Node software, an update on Protocol v2, and on November 9 new iOS, Android and Desktop releases with further voluntary node upgrades and progress on a unified client.
mailcow vs Session: editorial side-by-side
mailcow
5.0COMMS
mailcow's November release patches an admin RCE and reworks sync jobs.
◆ Current state
mailcow ships named monthly releases with lettered revisions, mostly to pull in upstream security fixes for SOGo, Nginx, Redis, Unbound and Rspamd. The November release goes further: it fixes a remote code execution flaw reachable by admins and domain admins, adds mailbox groups, and reworks imapsync so sync jobs reference a separate source. It also caps request bodies at 64 MB, which breaks large SOGo and ActiveSync mail unless NGINX_MAX_BODY_SIZE is raised.
◆ Where it's heading
The monthly security cadence holds, but recent releases carry more of mailcow's own features and API changes alongside the upstream bumps. Breaking changes now come with explicit migration steps, which suggests the API is being cleaned up for integrators.
◆ Prediction
Expect the promised RCE advisory details next week and a lettered revision within weeks to address fallout from the sync job API and body-size changes.
Session
5.0COMMS
Session ships new app versions and node upgrades while Pro stays on hold.
◆ Current state
Session's 2026 started with a funding scare, then community support restored its runway in June. Session Pro reached a beta in app stores in September before its launch was paused in October during talks with an allied privacy ecosystem. Since then the work is infrastructure: lighter Session Node software, an update on Protocol v2, and on November 9 new iOS, Android and Desktop releases with further voluntary node upgrades and progress on a unified client.
◆ Where it's heading
With Pro paused, Session is spending its effort on the network and the client codebase: lighter nodes, Protocol v2 with forward secrecy and post-quantum encryption, and one client for all platforms. Monetization waits on the outside talks.
◆ Prediction
Expect a Protocol v2 alpha or the unified client to be the next visible release; Pro's timing depends on talks the entries do not detail.
Alternatives to mailcow and Session
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 mailcow or Session.
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 mailcow alternatives → · See all Session alternatives →
Recent activity from mailcow and Session
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 4d agoSessionDevelopment Update - New Releases and Session Node Upgrades
- 9d agomailcowMoovember 2026: admin RCE fix, mailbox groups, imapsync rework
- 23d agomailcow🎃🐮 Mooctober 2026 | Security Update: PHP 8.2.35, SOGo 5.12.12 & Nginx 1.30.6
- 26d agoSessionSmaller nodes, stronger encryption: Oxen 11.7, Storage Server 2.12 and Session Router 1.1
- 1mo agoSessionSession Protocol v2: An Update on PFS, Post-Quantum and Linked Devices
- 1mo agoSessionSession is taking part in Octant's Epoch 13 privacy round
- 1mo agomailcow2026-09a: Rspamd 4.2.1 and postfix-tlspol bumps
- 1mo agoSessionDevelopment Update - Stability Fixes and Network Improvements
- 1mo agomailcow🍂🐮 Mootember 2026 | Unbound 1.26.1, SOGo 5.12.11 & Redis 7.4.11
- 2mo agoSessionSession Pro beta submitted to app stores
- 2mo agomailcow🏖️🐮 Mooly 2026 | Postfix 3.10.12, Rspamd 4.1.0 & Nginx 1.30.3 - Revision B
- 3mo agomailcow🏖️🐮 Mooly 2026 | Postfix 3.10.12, Rspamd 4.1.0 & Nginx 1.30.3 - Revision A
Frequently asked questions
What is the difference between mailcow and Session?
They serve adjacent needs but don't currently overlap on shipped themes. mailcow and Session are shipping at a similar cadence (velocity 5.0 vs 5.0, 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 mailcow better than Session?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. mailcow and Session are shipping at a similar cadence (velocity 5.0 vs 5.0, 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 mailcow?
Top mailcow alternatives in Comms are ranked by recent ship velocity. Browse the "mailcow alternatives" section above for the current picks, or visit /alternatives/mailcow for the full list with editorial commentary on each.
What are the best alternatives to Session?
Top Session alternatives in Comms are ranked by recent ship velocity. Browse the "Session alternatives" section above for the current picks, or visit /alternatives/session for the full list with editorial commentary on each.