Nation-scale Matrix deployments will fail using the community version of Synapse

Original Article ↗ Hacker News Discussion ↗

Business model and licensing

  • Synapse remains AGPL-licensed FOSS; Synapse Pro adds proprietary Rust-based worker implementations aimed at very large deployments (≈100k+ users / “nation-scale”).
  • Element staff say Synapse Pro exists to solve a funding crisis caused by “freerider” system integrators and governments using FOSS Synapse at scale without paying upstream, contributing to layoffs and stalled development.
  • Earlier attempts to monetize via enterprise-only features and AGPL relicensing are described as insufficient; Synapse Pro is framed as a stronger incentive for big deployments to fund upstream work.
  • Critics see this as open core, a bait‑and‑switch, or using FOSS as marketing, and worry about future creep of more features into the proprietary tier.
  • Others argue that developers must be paid, nothing was taken away, and this is a pragmatic compromise; some suggest “eventually open source” licenses as an alternative.

Performance, scalability, and Matrix design

  • Many commenters report long‑standing performance issues: high RAM/CPU use, slow joins in large federated rooms, and delayed notifications even on small instances.
  • Element staff stress that small‑server slowness is due to protocol/algorithmic issues (state resolution, state storage, federation retries, full‑mesh federation), not Python vs Rust; fixes for these are promised in FOSS Synapse.
  • Synapse Pro is said to only address bottlenecks for very large horizontally scaled worker setups (reduced CPU, better scaling).
  • Some are skeptical that core performance can be fixed at all, arguing Matrix’s document‑replication design is inherently less scalable than message‑passing protocols.

Community reaction and trust

  • Several long‑time admins and contributors feel “rug‑pulled” and less willing to advocate Matrix as public infrastructure, especially when “nation‑scale” capability is tied to proprietary code.
  • Others report years of solid experience with Synapse and express strong support, viewing Synapse Pro as necessary to “keep the lights on.”
  • Confusion over messaging (original blog tone, “Synapse Pro” naming, Dendrite’s status, CLAs, shifting priorities like Element X and MAS) contributes to distrust; Element later updates the post to clarify that general performance work will land in FOSS first.

Alternatives and protocol comparisons

  • XMPP (notably ejabberd) is frequently cited as a more mature, scalable alternative used historically by large services; some have migrated back and are happier.
  • Zulip is praised for team chat but lacks federation and broad‑audience appeal.
  • A linked piece contrasts Matrix’s document‑replication model with XMPP’s message passing, arguing Matrix can’t match XMPP’s scalability by design.