Krisp
Krisp adds AI voice-fraud security to its Call Center AI stack
A side-by-side editorial comparison of Shortwave and Stalwart — release velocity, themes, recent moves, and the top alternatives to consider.
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.
A Rust mail server chasing full standards conformance, one biweekly release at a time.
Stalwart is an all-in-one, Rust-based mail and collaboration server — JMAP, IMAP, SMTP, CalDAV, OAuth/OIDC — shipping patch releases every one to two weeks. The recent cadence is dominated by standards implementation (DKIM2, DMARCbis, IDN, JMAP conformance) paired with a long tail of protocol-correctness fixes. It reads as a project pushing hard to be a complete, spec-conformant replacement for legacy mail stacks.
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.
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.
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 is an all-in-one, Rust-based mail and collaboration server — JMAP, IMAP, SMTP, CalDAV, OAuth/OIDC — shipping patch releases every one to two weeks. The recent cadence is dominated by standards implementation (DKIM2, DMARCbis, IDN, JMAP conformance) paired with a long tail of protocol-correctness fixes. It reads as a project pushing hard to be a complete, spec-conformant replacement for legacy mail stacks.
The arc is breadth-then-correctness: add a new RFC or draft, then spend the next releases hardening it against conformance test suites. FreeBSD support and encryption-at-rest point to a parallel push on deployment surface and security posture, not just protocol coverage. Expect the standards backlog — email auth, JMAP, calendaring — to keep driving the release notes.
The next releases likely continue the pattern: more JMAP and CalDAV conformance fixes, plus follow-through on the freshly landed DKIM2 and DMARCbis code as those drafts evolve.
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.
Krisp adds AI voice-fraud security to its Call Center AI stack
Wire ships frequent production builds, but most carry no documented user-facing changes.
Courier is turning its notification API into a full messaging orchestration platform.
BenchApp is porting its mobile team app to the web, one screen at a time
Matrix grinds toward 2.0: sliding sync lands in spec, v1.19 ships long-pending features.
Elastic Email's public feed is content marketing aimed at AI-app builders and small agencies.
See all Shortwave alternatives → · See all Stalwart alternatives →
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
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.
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.
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.
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.