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Comparison · Comms
Shortwave vs Stalwart
A side-by-side editorial comparison of Shortwave and Stalwart — release velocity, themes, recent moves, and the top alternatives to consider.
Shortwave vs Stalwart: at a glance
What is Shortwave?
Shortwave keeps folding autonomy into the inbox, one AI action at a time.
Shortwave has moved decisively from an AI-assisted email client to an inbox that acts on the user's behalf. The assistant reads, drafts, organizes, and — via the Tasklet integration — triggers automated workflows across thousands of apps, with its work surfaced inside Shortwave rather than buried in Gmail. Every release since late 2024 has pushed more of the email workflow out of the user's hands and into the model's.
What is Stalwart?
SCIM v2 lands in the Enterprise tier, opening a provisioning surface beside the protocol work.
Stalwart ships weekly, and 0.16.20 breaks a long run of pure spec-completeness work by adding SCIM v2 to the Enterprise tier: core schema (RFC 7643), protocol (RFC 7644), cursor-based pagination (RFC 9865), the SCIM interoperability profile and the IPSIE lifecycle profile. The rest of the release is the established mix - conference links in calendar invites and alarms, 25 interface translations, and a fix run covering DANE lookup and failure semantics, Redis Sentinel deployments where rediss:// URLs connected to the master in cleartext, and cluster node leases that left removed nodes marked stale indefinitely.
Shortwave vs Stalwart: editorial side-by-side
Shortwave
0.0COMMS
Shortwave keeps folding autonomy into the inbox, one AI action at a time.
◆ Current state
Shortwave has moved decisively from an AI-assisted email client to an inbox that acts on the user's behalf. The assistant reads, drafts, organizes, and — via the Tasklet integration — triggers automated workflows across thousands of apps, with its work surfaced inside Shortwave rather than buried in Gmail. Every release since late 2024 has pushed more of the email workflow out of the user's hands and into the model's.
◆ Where it's heading
The direction is a steadily widening action surface: MCP connectors to external tools, AI Memories, voice, and now trigger-based automation all frame email as an agent runtime rather than a reading pane. Model choices track the frontier closely — Claude 3.7 to Sonnet 4 to the 4.6 family — keeping capability tied to whatever the best available model can do. The team ships broadly across web, desktop, iOS, and Android each cycle.
◆ Prediction
The next moves most likely deepen autonomous execution — more trigger types and tighter loops where the assistant acts with less confirmation — rather than adding new surface features.
Stalwart
6.3COMMS
SCIM v2 lands in the Enterprise tier, opening a provisioning surface beside the protocol work.
◆ Current state
Stalwart ships weekly, and 0.16.20 breaks a long run of pure spec-completeness work by adding SCIM v2 to the Enterprise tier: core schema (RFC 7643), protocol (RFC 7644), cursor-based pagination (RFC 9865), the SCIM interoperability profile and the IPSIE lifecycle profile. The rest of the release is the established mix - conference links in calendar invites and alarms, 25 interface translations, and a fix run covering DANE lookup and failure semantics, Redis Sentinel deployments where rediss:// URLs connected to the master in cleartext, and cluster node leases that left removed nodes marked stale indefinitely.
◆ Where it's heading
The protocol gap-closing continues, with DANE, iMIP, CalDAV and JMAP absorbing corrections every release, but SCIM points at a different axis: who is expected to deploy this. Provisioning, per-tenant branding, cluster lease handling and the recovery-admin impersonation fixes are operator concerns rather than mail-standard concerns, and they have been accumulating since 0.16.15. Calendar remains the least settled surface, now extending into localization rather than correctness alone.
◆ Prediction
SCIM shipped with the interoperability and IPSIE profiles attached, so the near-term work is likely the directory-side corrections that follow first contact with real identity providers - the same pattern the LDAP and SQL directory integrations have been producing. The 25 new translations open a localization surface that has not yet had to survive a release cycle.
Alternatives to Shortwave 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 Shortwave or Stalwart.
Synapse
Synapse publishes only a changelog link, so its feed records releases without describing them
Element X Android
Element X Android ships roughly weekly, alternating real features with fix rounds
Wire
Calling is the one surface Wire's web client touches in every documented release.
Zoho Cliq
Zoho retells Cliq 7.0 as an AI story, and lets customers pick whose model tells it.
Rocket.Chat
Rocket.Chat finishes the 8.8 calling work while the licence wall for SSO gets a date.
See all Shortwave alternatives → · See all Stalwart alternatives →
Recent activity from Shortwave and Stalwart
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 3d agoStalwartSCIM v2 provisioning lands in the Enterprise tier ⚡
- 8d agoStalwartMySQL key columns need a manual ALTER; Sieve gains spam-score vars
- 15d agoStalwartResource limits arrive for inbound reports and RocksDB caches
- 22d agoStalwartIMAP gains UIDONLY, UIDBATCHES and message-limit extensions
- 1mo agoStalwartJMAP delivery push arrives; strict relays stop rejecting calendar mail
- 1mo agoStalwartFix-only release: JMAP semantics and a credential escalation
- 6mo agoShortwaveUpgraded to Claude Sonnet & Opus 4.6
- 7mo agoShortwaveFully automate your email with Tasklet 🔗 ⚡
- 11mo agoShortwaveEnhanced AI performance & collaboration
- 1y agoShortwaveIntegrate the AI with all your apps 🔌 ⚡
- 1y agoShortwaveTalk to your inbox 🎙️
- 1y agoShortwaveOrganize your inbox with AI ✨
Frequently asked questions
What is the difference between Shortwave and Stalwart?
They serve adjacent needs but don't currently overlap on shipped themes. Stalwart is currently shipping more aggressively (velocity 6.3 vs 0.0), 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 Shortwave better than Stalwart?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Stalwart is currently shipping more aggressively (velocity 6.3 vs 0.0), 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 Shortwave?
Top Shortwave alternatives in Comms are ranked by recent ship velocity. Browse the "Shortwave alternatives" section above for the current picks, or visit /alternatives/shortwave 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.