Stalwart vs Telnyx
Side-by-side trajectory, velocity, and editorial themes.
Stalwart races to implement the newest email standards across its all-in-one server
Stalwart is an open-source, all-in-one mail and collaboration server (SMTP/IMAP/JMAP/CalDAV) shipping a fast 0.16.x point-release train. Recent releases are dominated by standards implementation and protocol-conformance work, layered over steady security hardening and a long tail of targeted bug fixes.
The product is doubling down on being the most standards-complete self-hosted mail server: early DKIM2 and DMARCbis authentication, IDN support, encryption-at-rest for S/MIME, and a sustained push to pass the JMAP test suite. Security hardening runs alongside — DANE downgrade-attack defenses, auto-ban fixes, binary attestation on every build.
Expect continued rapid 0.16.x releases advancing draft email-authentication standards and JMAP conformance; a larger 0.17 or 1.0 milestone becomes likely once the JMAP suite fully passes and the DKIM2/DMARCbis drafts stabilize.
Telnyx is turning its carrier network into an agent-native voice AI platform.
Telnyx's changelog is now dominated by Voice AI Assistants and agentic infrastructure rather than core telephony. Recent work hardens assistants for real call flows (interruption control, filler speech, browser-side tool calls) while extending sovereign inference into new regions and languages. Alongside this, Number Reputation and Branded Calling show it is also shoring up the deliverability side of outbound calling.
Two arcs are converging. One makes Voice AI Assistants production-grade for live call centers — tunable barge-in, scripted filler during tool calls, and now client-side JavaScript execution. The other is regional and sovereign AI: Arabic speech models followed by UAE data residency and GPU inference point at a deliberate MENA expansion. Telnyx is positioning the full stack — carrier, inference, and agent runtime — under one roof.
Expect more agent-runtime primitives (additional tool types, wider language coverage) and further sovereign inference regions; the browser-side tool calling suggests deeper client SDK work is next.
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