← Back to home
Comparison · Comms

mailcow vs Converse.js

A side-by-side editorial comparison of mailcow and Converse.js — release velocity, themes, recent moves, and the top alternatives to consider.

mailcow vs Converse.js: at a glance

FeaturemailcowConverse.js
SectorCommsComms
Velocity score5.00.0
Sparks · 30d00
Top themesmail-server, self-hosted, cve-response, xss-hardeningxmpp, omemo-encryption, e2e-usability, pubsub-api
Last editorial update2d ago3h ago
WebsiteVisit →Visit →

What is mailcow?

Six releases, and every one of them is a security update in some form.

mailcow ships on a monthly tag with lettered revisions, and this window contains no release that isn't security-driven. The May line ran to three revisions in two weeks — an unnamed fix with a CVE identifier withheld until later, SOGo 5.12.8 covering four upstream issues, an unbound CVE, HTML escaping added to the quarantine table, sieve filter editor and queue manager. July brought Rspamd 4.1.0 and later 4.1.4, nginx 1.30.3 and a CVE fix, Postfix moved off bookworm, and a release described only as hardening.

Read the full mailcow trajectory →

What is Converse.js?

Converse.js 14 lands OMEMO:2 — the browser XMPP client catches up on modern encryption.

Converse.js reached 14.0.0 in June 2026 after a tight beta train, and the release is defined by one thing: support for OMEMO:2, the current revision of XMPP's end-to-end encryption. The surrounding work is all encryption ergonomics — per-chat encryption state remembered across chat-close and re-login, an explicit error surfaced for undecryptable messages instead of silently dropping them, the toggle hidden on untrusted devices, and original filenames preserved on encrypted image download. New PubSub API methods for create, subscribe and unsubscribe round out the release.

Read the full Converse.js trajectory →

mailcow vs Converse.js: editorial side-by-side

M
mailcow
COMMS
5.0

Six releases, and every one of them is a security update in some form.

◆ Current state

mailcow ships on a monthly tag with lettered revisions, and this window contains no release that isn't security-driven. The May line ran to three revisions in two weeks — an unnamed fix with a CVE identifier withheld until later, SOGo 5.12.8 covering four upstream issues, an unbound CVE, HTML escaping added to the quarantine table, sieve filter editor and queue manager. July brought Rspamd 4.1.0 and later 4.1.4, nginx 1.30.3 and a CVE fix, Postfix moved off bookworm, and a release described only as hardening.

◆ Where it's heading

Two distinct pressures are visible. One is upstream: mailcow bundles Postfix, Rspamd, SOGo, nginx, unbound and Dovecot, so every one of their advisories becomes a mailcow release, and the base image migration from bookworm to trixie is that same maintenance surfacing at the OS layer. The other is the project's own web UI, where output escaping is being retrofitted view by view — quarantine table, sieve editor, queue manager, quarantine overview — which reads as a systematic pass rather than isolated reports. Earlier releases in the feed show where feature work went when it happened: forced 2FA, ACME DNS-01 challenges, and admin controls over EAS and DAV access.

◆ Prediction

Expect the monthly-plus-revisions rhythm to continue with upstream component bumps driving most of it, and the web UI escaping pass to reach the remaining admin views.

C0.0

Converse.js 14 lands OMEMO:2 — the browser XMPP client catches up on modern encryption.

◆ Current state

Converse.js reached 14.0.0 in June 2026 after a tight beta train, and the release is defined by one thing: support for OMEMO:2, the current revision of XMPP's end-to-end encryption. The surrounding work is all encryption ergonomics — per-chat encryption state remembered across chat-close and re-login, an explicit error surfaced for undecryptable messages instead of silently dropping them, the toggle hidden on untrusted devices, and original filenames preserved on encrypted image download. New PubSub API methods for create, subscribe and unsubscribe round out the release.

◆ Where it's heading

The project is closing the gap between having encryption and having usable encryption. Almost every OMEMO change in this cycle is about failure modes users previously had to guess at: a silently dropped message, an encryption toggle offered where it cannot work, an abandoned bundle that never self-healed. That is the work a client does when its encryption is no longer a demo but something people depend on daily. Dropping client-compress for native browser APIs points the same way — fewer bundled dependencies in a security-sensitive path.

◆ Prediction

Expect the 14.x line to settle into interoperability fixes as OMEMO:2 meets other XMPP clients in the wild, with the new PubSub API the most likely base for the next feature layer.

Alternatives to mailcow and Converse.js

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 Converse.js.

See all mailcow alternatives → · See all Converse.js alternatives →

Recent activity from mailcow and Converse.js

Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.

  1. 4d agomailcow🏖️🐮 Mooly 2026 | Postfix 3.10.12, Rspamd 4.1.0 & Nginx 1.30.3 - Revision A
  2. 21d agomailcow🏖️🐮 Mooly 2026 | Postfix 3.10.12, Rspamd 4.1.0 & Nginx 1.30.3
  3. 1mo agoConverse.jsOMEMO:2 encryption support ships in Converse 14
  4. 1mo agoConverse.jsOMEMO bundle self-healing and new PubSub API methods
  5. 1mo agoConverse.jslibomemo.js dependency bump
  6. 1mo agoConverse.jsclient-compress replaced with native browser APIs
  7. 1mo agoConverse.jsFirst beta carrying the OMEMO usability fixes
  8. 2mo agoConverse.jsReaction attribution and MUC JID parsing fixes
  9. 2mo agomailcowThird May revision: unbound CVE and nginx 1.30.2
  10. 2mo agomailcowSecond May revision: quarantine table HTML escaping
  11. 2mo agomailcowSOGo 5.12.8 covering four upstream security issues
  12. 2mo agomailcowMay base release: undisclosed CVE plus web UI escaping

Frequently asked questions

What is the difference between mailcow and Converse.js?

They serve adjacent needs but don't currently overlap on shipped themes. mailcow is currently shipping more aggressively (velocity 5.0 vs 0.0), with 0 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 mailcow better than Converse.js?

Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. mailcow is currently shipping more aggressively (velocity 5.0 vs 0.0), with 0 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 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 Converse.js?

Top Converse.js alternatives in Comms are ranked by recent ship velocity. Browse the "Converse.js alternatives" section above for the current picks, or visit /alternatives/converse-js for the full list with editorial commentary on each.