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Comparison · Infra & APIs

Ably vs Nebula

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

Ably vs Nebula: at a glance

FeatureAblyNebula
SectorInfra & APIsInfra & APIs
Velocity score7.52.5
Sparks · 30d20
Top themesai transport, realtime messaging, agents, mau-billingmesh-vpn, overlay-network, ipv6, performance
Last editorial update21h ago11d ago
Website—Visit →

What is Ably?

Ably's AI Transport hits 1.0 and plugs straight into Vercel's useChat with resumable streams.

Ably is repositioning its realtime pub/sub network as the transport layer for AI agent output. AI Transport JS 1.0 runs on ordinary Pub/Sub channels and ships adaptors for the Vercel AI SDK, OpenAI Responses API and AG-UI, plus a useChat transport that resumes a stream after a reload. It lands a week after the switch to monthly-active-user pricing and breaking SDK majors that split every client into device and server packages.

Read the full Ably trajectory →

What is Nebula?

Nebula 1.12 adds optional offloading for throughput after a run of platform fixes.

Nebula is a peer-to-peer mesh VPN with its own certificate authority. Since v1.10.0 added IPv6 and multiple overlay addresses, releases have dealt with the fallout: v1.11.1 fixed an IPv6 firewall bypass, and v1.11.2 in September fixed IPv6 MTU on Windows, local address discovery on Android 11+, and checksums for traffic to a host's own IPv6 address on macOS. v1.12.0 on October 29 added optional UDP and TUN offloading, planned to become the default later, and stricter firewall rule parsing.

Read the full Nebula trajectory →

Ably vs Nebula: editorial side-by-side

A
Ably
INFRA · APIS
7.5

Ably's AI Transport hits 1.0 and plugs straight into Vercel's useChat with resumable streams.

◆ Current state

Ably is repositioning its realtime pub/sub network as the transport layer for AI agent output. AI Transport JS 1.0 runs on ordinary Pub/Sub channels and ships adaptors for the Vercel AI SDK, OpenAI Responses API and AG-UI, plus a useChat transport that resumes a stream after a reload. It lands a week after the switch to monthly-active-user pricing and breaking SDK majors that split every client into device and server packages.

◆ Where it's heading

The November releases fit one plan: split clients so MAU billing can count end users, then make the AI layer a thin adaptor on top of the same channels used for chat, presence and LiveObjects. Server-side additions in Java and JS (HTTP LiveObjects, channel pools, a Temporal plugin) point at agent backends as the intended publisher.

◆ Prediction

Expect more agent framework adaptors and server SDKs reaching AI Transport parity, with Chat and LiveObjects examples built around agents joining human conversations.

N
Nebula
INFRA · APIS
2.5

Nebula 1.12 adds optional offloading for throughput after a run of platform fixes.

◆ Current state

Nebula is a peer-to-peer mesh VPN with its own certificate authority. Since v1.10.0 added IPv6 and multiple overlay addresses, releases have dealt with the fallout: v1.11.1 fixed an IPv6 firewall bypass, and v1.11.2 in September fixed IPv6 MTU on Windows, local address discovery on Android 11+, and checksums for traffic to a host's own IPv6 address on macOS. v1.12.0 on October 29 added optional UDP and TUN offloading, planned to become the default later, and stricter firewall rule parsing.

◆ Where it's heading

The IPv6 work has moved from security fixes to per-platform correctness, and 1.12 turns to throughput. Offloading starting as opt-in, with a stated plan to make it default, sets up the next release cycle.

◆ Prediction

Expect 1.12.x patches for offloading edge cases, and a later release that turns offloading on by default as announced.

Alternatives to Ably and Nebula

Other Infra & APIs 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 Ably or Nebula.

See all Ably alternatives → · See all Nebula alternatives →

Recent activity from Ably and Nebula

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

  1. 1d agoAblyAI Transport 1.0 makes Ably a resumable transport for AI chat ⚡
  2. 2d agoAblyJava SDK 2.1 reads and updates LiveObjects over HTTP
  3. 2d agoAblyJS SDK 3.1 adds channel pools and a Temporal plugin
  4. 4d agoAblyAbly Kafka Connector v4.2.1
  5. 8d agoAblyMonthly active user (MAU) pricing ⚡
  6. 8d agoAblyAbly Chat React UI Kit v0.4.0
  7. 15d agoNebulaRelease v1.12.0
  8. 1mo agoNebulav1.11.2 fixes IPv6 MTU on Windows and address discovery on Android
  9. 2mo agoNebulaIPv6 firewall bypass: unparsed protocols matched TCP/UDP rules
  10. 3mo agoNebulaBreaking: slog logging, corrected firewall reject/drop direction
  11. 9mo agoNebulaP256 signature malleability allowed blocklist bypass
  12. 9mo agoNebulaFix panic in use_system_route_table introduced by the previous release

Frequently asked questions

What is the difference between Ably and Nebula?

They serve adjacent needs but don't currently overlap on shipped themes. Ably is currently shipping more aggressively (velocity 7.5 vs 2.5), with 2 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 Ably better than Nebula?

Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Ably is currently shipping more aggressively (velocity 7.5 vs 2.5), with 2 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Infra & APIs products to evaluate alongside.

What are the best alternatives to Ably?

Top Ably alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "Ably alternatives" section above for the current picks, or visit /alternatives/ably for the full list with editorial commentary on each.

What are the best alternatives to Nebula?

Top Nebula alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "Nebula alternatives" section above for the current picks, or visit /alternatives/nebula-networking for the full list with editorial commentary on each.