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Roundcube vs Stalwart

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

Shared themes:self-hosted

Roundcube vs Stalwart: at a glance

FeatureRoundcubeStalwart
SectorCommsComms
Velocity score5.05.0
Sparks · 30d00
Top themeswebmail, php, security, oidcmail-server, jmap, email-authentication, standards-implementation
Last editorial update2d ago10h ago
WebsiteVisit →Visit →

What is Roundcube?

After four years, Roundcube 1.7 lands — and the release stream is otherwise all CVEs

Roundcube maintains two lines in lockstep: 1.6 as LTS and 1.7 as stable, with security fixes released to both on the same day. The vulnerability stream is heavy and varied — stored XSS via an unescaped attachment MIME type (CVE-2026-54432), a pre-auth SQL injection in the virtuser_query plugin, CSS injection through SVG animate, SSRF bypasses via local address URLs, an infinite loop in the TNEF decoder. Version 1.7.0, released in May after almost four years of development, is the only feature release in the window.

Read the full Roundcube trajectory →

What is Stalwart?

Stalwart keeps chasing standards nobody has implemented yet — DKIM2, DMARCbis, now JMAP email push.

Stalwart is a single-binary mail and collaboration server covering JMAP, IMAP, SMTP, CalDAV and CardDAV. The 0.16.x line ships roughly weekly and its additions cluster in one place: implementing IETF drafts and fresh RFCs ahead of the field, while a long tail of JMAP conformance and MTA edge-case fixes runs underneath. The latest release adds JMAP email delivery push notifications, completing a push stack built across the last three releases.

Read the full Stalwart trajectory →

Roundcube vs Stalwart: editorial side-by-side

R5.0

After four years, Roundcube 1.7 lands — and the release stream is otherwise all CVEs

◆ Current state

Roundcube maintains two lines in lockstep: 1.6 as LTS and 1.7 as stable, with security fixes released to both on the same day. The vulnerability stream is heavy and varied — stored XSS via an unescaped attachment MIME type (CVE-2026-54432), a pre-auth SQL injection in the virtuser_query plugin, CSS injection through SVG animate, SSRF bypasses via local address URLs, an infinite loop in the TNEF decoder. Version 1.7.0, released in May after almost four years of development, is the only feature release in the window.

◆ Where it's heading

The arc is a long-lived webmail codebase paying down structural risk. 1.7.0's headline changes are defensive rather than user-facing: a mandatory public_html/ entry point so installations aren't exposed by default, improved OAuth2/OIDC support including discovery and logout, removed code bloat and automated code style and quality checks. Everything since has been paired security releases across both lines, several of them reporting classes of bug — sanitizer bypasses, injection through plugin queries — that the 1.7 hardening work is aimed at. Expect the security cadence to stay high while the 1.6 LTS remains supported.

◆ Prediction

Expect continued same-day paired security releases on 1.6 and 1.7, with 1.7.x accruing incremental OIDC and sanitizer hardening before any 1.8 work becomes visible.

S5.0

Stalwart keeps chasing standards nobody has implemented yet — DKIM2, DMARCbis, now JMAP email push.

◆ Current state

Stalwart is a single-binary mail and collaboration server covering JMAP, IMAP, SMTP, CalDAV and CardDAV. The 0.16.x line ships roughly weekly and its additions cluster in one place: implementing IETF drafts and fresh RFCs ahead of the field, while a long tail of JMAP conformance and MTA edge-case fixes runs underneath. The latest release adds JMAP email delivery push notifications, completing a push stack built across the last three releases.

◆ Where it's heading

The push story is the clearest arc: Web Push payload and subscription fixes in 0.16.10, VAPID per RFC 9749 in 0.16.14, and the emailpush draft in 0.16.16. Parallel to it, 0.16.12 landed DKIM2 and the DMARCbis trio, and the fix lists keep narrowing toward strict-spec behaviour — DMARC alignment reporting, SMTP line-length limits, BDAT error codes. Stalwart is positioning as the reference implementation of modern mail standards rather than competing on features.

◆ Prediction

Expect the JMAP push work to keep filling in — subscription lifecycle, delivery semantics — alongside continued DKIM2 and DMARCbis refinement as those drafts move. The fix cadence suggests operational hardening around clustering and Redis locking is the other near-term thread.

Alternatives to Roundcube 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 Roundcube or Stalwart.

See all Roundcube alternatives → · See all Stalwart alternatives →

Recent activity from Roundcube and Stalwart

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

  1. 16h agoStalwartv0.16.16 — JMAP email push, plus Redis lock and SMTP relay fixes
  2. 7d agoStalwartv0.16.15 — JMAP, MTA, and auth privilege fixes
  3. 13d agoStalwartv0.16.14 — VAPID Web Push plus push and calendar fixes
  4. 21d agoStalwartv0.16.13 — FreeBSD support and OAuth/JMAP fixes
  5. 27d agoStalwartv0.16.12 — DKIM2 and DMARCbis email-authentication support
  6. 28d agoRoundcubeRoundcube LTS patches attachment XSS, SSRF and a TNEF loop
  7. 28d agoRoundcubeRoundcube 1.7 gets the same attachment XSS and SSRF fixes
  8. 1mo agoStalwartv0.16.11 — S/MIME encryption-at-rest and Redis Sentinel backend
  9. 1mo agoRoundcubeRoundcube LTS fixes a pre-auth SQL injection in virtuser_query
  10. 1mo agoRoundcubeRoundcube 1.7.1 carries the pre-auth SQL injection fixes
  11. 2mo agoRoundcubeRoundcube Webmail 1.7.0
  12. 4mo agoRoundcubeRoundcube 1.6.15 fixes an SVG animate bypass and search regressions

Frequently asked questions

What is the difference between Roundcube and Stalwart?

Both compete on the same themes — self-hosted — within Comms. Roundcube and Stalwart are shipping at a similar cadence (velocity 5.0 vs 5.0, both within Sparkpulse's "active" band). See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.

Is Roundcube better than Stalwart?

Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Roundcube and Stalwart are shipping at a similar cadence (velocity 5.0 vs 5.0, both within Sparkpulse's "active" band). For your specific use case, the alternatives sections above list other Comms products to evaluate alongside.

What are the best alternatives to Roundcube?

Top Roundcube alternatives in Comms are ranked by recent ship velocity. Browse the "Roundcube alternatives" section above for the current picks, or visit /alternatives/roundcube 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.