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Comparison · Comms
Signal vs Stalwart
A side-by-side editorial comparison of Signal and Stalwart — release velocity, themes, recent moves, and the top alternatives to consider.
Signal vs Stalwart: at a glance
What is Signal?
Closing the UX gap while pushing the crypto frontier.
Signal is running two parallel programs: a cryptographic agenda (post-quantum ratchet, defenses against Microsoft Recall) and a long-overdue UX parity push (secure backups, polls, pinned messages, group labels). The product has matured past pure privacy infrastructure and now ships features mainstream users have asked for for years. Each direction reinforces the brand: still the most paranoid messenger, but no longer the one that loses your chat history when your phone breaks.
What is Stalwart?
Stalwart is shipping email's next-generation auth stack while the specs are still in draft.
Stalwart is an all-in-one mail and collaboration server — SMTP, IMAP, JMAP, CalDAV, CardDAV and WebDAV in one binary — releasing every one to two weeks on the 0.16.x line. The last two months read as a standards campaign: DKIM2 and the full DMARCbis set in 0.16.12, VAPID push in 0.16.14, FreeBSD support in 0.16.13, and a run of IMAP extensions (UIDONLY, UIDBATCHES, MESSAGELIMIT/SAVELIMIT) in 0.16.17. Between the additions, most of each release is JMAP conformance repair driven by the jmap-test-suite.
Signal vs Stalwart: editorial side-by-side
Signal
0.0COMMS
Closing the UX gap while pushing the crypto frontier.
◆ Current state
Signal is running two parallel programs: a cryptographic agenda (post-quantum ratchet, defenses against Microsoft Recall) and a long-overdue UX parity push (secure backups, polls, pinned messages, group labels). The product has matured past pure privacy infrastructure and now ships features mainstream users have asked for for years. Each direction reinforces the brand: still the most paranoid messenger, but no longer the one that loses your chat history when your phone breaks.
◆ Where it's heading
The cadence over the last 12 months shows a deliberate alternation between cryptographic milestones and feature catch-up. Backups, polls, pinned messages, and group labels are the kind of work Signal historically deferred; shipping them in quick succession signals a strategic decision to remove every easy reason a user might leave for WhatsApp or iMessage. Meanwhile SPQR positions the protocol for the next decade of cryptographic threat models, keeping the security story intact while the UX story finally catches up.
◆ Prediction
Secure backups will graduate from Android beta to iOS and Desktop within the next two releases. Expect another round of feature-parity work — message editing depth, richer media handling, or reactions — before the next protocol-level cryptographic move.
Stalwart
5.0COMMS
Stalwart is shipping email's next-generation auth stack while the specs are still in draft.
◆ Current state
Stalwart is an all-in-one mail and collaboration server — SMTP, IMAP, JMAP, CalDAV, CardDAV and WebDAV in one binary — releasing every one to two weeks on the 0.16.x line. The last two months read as a standards campaign: DKIM2 and the full DMARCbis set in 0.16.12, VAPID push in 0.16.14, FreeBSD support in 0.16.13, and a run of IMAP extensions (UIDONLY, UIDBATCHES, MESSAGELIMIT/SAVELIMIT) in 0.16.17. Between the additions, most of each release is JMAP conformance repair driven by the jmap-test-suite.
◆ Where it's heading
The project is building toward being the reference implementation of the modern mail stack — JMAP first, with the classic protocols held at parity rather than left behind. The fix lists have shifted in character over these eight releases: less "feature does not work", more "spec detail is wrong", which is what a codebase looks like as it converges on conformance. Security and multi-tenancy fixes keep appearing alongside the protocol work, indicating real deployments are exercising the newer subsystems.
◆ Prediction
The next releases most likely track revisions to the drafts already implemented — DKIM2, JMAP push and the calendar drafts are all still moving — rather than adding another protocol surface. Expect continued JMAP conformance fixes until the test suite stops producing them.
Alternatives to Signal and Stalwart
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 Signal or Stalwart.
Help Scout
Help Scout keeps adding channels — now a portal customers sign into
Synapse
Synapse alternates release candidates with security patches on a tight two-week cycle
Canary Mail
Canary Mail ships maintenance across four platform lines; features have gone quiet since April.
Bandwidth
Bandwidth is closing the gaps that used to require a support ticket
Beeper
Beeper stopped aggregating apps and started merging the people inside them.
See all Signal alternatives → · See all Stalwart alternatives →
Recent activity from Signal and Stalwart
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 1d agoStalwartIMAP gains UIDONLY, UIDBATCHES and message-limit extensions
- 9d agoStalwartJMAP delivery push arrives; strict relays stop rejecting calendar mail
- 16d agoStalwartFix-only release: JMAP semantics and a credential escalation
- 23d agoStalwartVAPID lands for JMAP Web Push
- 1mo agoStalwartFreeBSD support, plus OAuth scopes for IMAP, SMTP and Sieve
- 1mo agoStalwartDKIM2 and the full DMARCbis suite ship in one release ⚡
- 4mo agoSignalLabel yourself
- 6mo agoSignalPut a pin in it
- 8mo agoSignalSignal Polls: Yes, no, maybe (yes!)
- 10mo agoSignalSignal Protocol and Post-Quantum Ratchets ⚡
- 11mo agoSignalIntroducing Signal Secure Backups ⚡
- 1y agoSignalBy Default, Signal Doesn't Recall ⚡
Frequently asked questions
What is the difference between Signal and Stalwart?
They serve adjacent needs but don't currently overlap on shipped themes. Stalwart 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 Signal better than Stalwart?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Stalwart 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 Signal?
Top Signal alternatives in Comms are ranked by recent ship velocity. Browse the "Signal alternatives" section above for the current picks, or visit /alternatives/signal for the full list with editorial commentary on each.
What are the best alternatives to Stalwart?
Top Stalwart alternatives in Comms are ranked by recent ship velocity. Browse the "Stalwart alternatives" section above for the current picks, or visit /alternatives/stalwart for the full list with editorial commentary on each.