← Back to home
Comparison · DevOps

Eclipse OpenJ9 vs Rivet

A side-by-side editorial comparison of Eclipse OpenJ9 and Rivet — release velocity, themes, recent moves, and the top alternatives to consider.

Eclipse OpenJ9 vs Rivet: at a glance

FeatureEclipse OpenJ9Rivet
SectorDevOpsDevOps
Velocity score5.07.5
Sparks · 30d03
Top themesjvm, java, jitserver, securityactors, ai agents, sqlite, forking
Last editorial update10d ago2d ago
WebsiteVisit →—

What is Eclipse OpenJ9?

OpenJ9 follows its 0.63 CVE release with a notes-less 0.63.0.1 respin.

Eclipse OpenJ9, IBM's alternative JVM, released 0.63.0 on October 28 with several CVE fixes and JITServer hardening against oversized and malformed messages. A 0.63.0.1 point tag followed on November 3 with only repository hashes. Earlier 2026 releases added JDK 26 support, moved the build fully to CMake, and patched CVEs in most cycles.

Read the full Eclipse OpenJ9 trajectory →

What is Rivet?

Rivet Actors can now fork in 20 ms, SQLite database included, without copying data.

Rivet builds infrastructure for long-lived actors and AI agents: BYOC, OpenTelemetry tracing, actor-scoped JWTs and agentOS Hosted VMs. The 3.0 Preview made Rivet a single stateless binary on S3, and the Rust SDK reached general availability on 6 November. On 11 November Rivet added actor forking: a fork starts in 20 ms with the original actor's state and SQLite database and costs nothing until it writes.

Read the full Rivet trajectory →

Eclipse OpenJ9 vs Rivet: editorial side-by-side

E5.0

OpenJ9 follows its 0.63 CVE release with a notes-less 0.63.0.1 respin.

◆ Current state

Eclipse OpenJ9, IBM's alternative JVM, released 0.63.0 on October 28 with several CVE fixes and JITServer hardening against oversized and malformed messages. A 0.63.0.1 point tag followed on November 3 with only repository hashes. Earlier 2026 releases added JDK 26 support, moved the build fully to CMake, and patched CVEs in most cycles.

◆ Where it's heading

OpenJ9 tracks the OpenJDK quarterly update train, with security fixes in most releases and JITServer getting the most attention. A quick point release after 0.63.0 usually means a fix for a regression or a missed JDK update, but the tag doesn't say which.

◆ Prediction

The next regular release should land with the January OpenJDK updates; what prompted 0.63.0.1 is unclear from the entries.

R
Rivet
DEVOPS
7.5

Rivet Actors can now fork in 20 ms, SQLite database included, without copying data.

◆ Current state

Rivet builds infrastructure for long-lived actors and AI agents: BYOC, OpenTelemetry tracing, actor-scoped JWTs and agentOS Hosted VMs. The 3.0 Preview made Rivet a single stateless binary on S3, and the Rust SDK reached general availability on 6 November. On 11 November Rivet added actor forking: a fork starts in 20 ms with the original actor's state and SQLite database and costs nothing until it writes.

◆ Where it's heading

Rivet keeps turning its S3-backed storage engine into features for agent workloads. Copy-on-write forking follows from the 3.0 storage design and gives agents a cheap way to branch a session, try something and discard it. The SDK and auth work of the past two months points to Rivet positioning actors as the runtime for agent backends.

◆ Prediction

Forking is likely to show up next in agentOS and the Pi integrations as a way to branch agent runs; the entries do not say when 3.0 leaves preview.

Alternatives to Eclipse OpenJ9 and Rivet

Other DevOps 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 Eclipse OpenJ9 or Rivet.

See all Eclipse OpenJ9 alternatives → · See all Rivet alternatives →

Recent activity from Eclipse OpenJ9 and Rivet

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

  1. 2d agoRivetIntroducing OpenOrange: Run Cloudflare Workers Anywhere ⚡
  2. 3d agoRivetIntroducing Actor Forking for SQLite ⚡
  3. 8d agoRivetRust SDK for Rivet Actors Is Now Generally Available
  4. 10d agoEclipse OpenJ9OpenJ9 0.63.0.1 point release, no notes published
  5. 16d agoEclipse OpenJ9Eclipse OpenJ9 v0.63.0
  6. 19d agoRivetIntroducing Rivet 3.0 Preview ⚡
  7. 1mo agoRivetIntroducing agentOS 0.4 & Hosted VMs
  8. 1mo agoRivetIntroducing Pi Durable for Rivet
  9. 2mo agoEclipse OpenJ9openj9-0.62.0 — release tagged (notes pending)
  10. 2mo agoEclipse OpenJ9openj9-0.61.0 — release tagged (notes pending)
  11. 3mo agoEclipse OpenJ9Eclipse OpenJ9 v0.60.0
  12. 6mo agoEclipse OpenJ9Eclipse OpenJ9 v0.59.0

Frequently asked questions

What is the difference between Eclipse OpenJ9 and Rivet?

They serve adjacent needs but don't currently overlap on shipped themes. Rivet is currently shipping more aggressively (velocity 7.5 vs 5.0), with 3 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 Eclipse OpenJ9 better than Rivet?

Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Rivet is currently shipping more aggressively (velocity 7.5 vs 5.0), with 3 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other DevOps products to evaluate alongside.

What are the best alternatives to Eclipse OpenJ9?

Top Eclipse OpenJ9 alternatives in DevOps are ranked by recent ship velocity. Browse the "Eclipse OpenJ9 alternatives" section above for the current picks, or visit /alternatives/eclipse-openj9 for the full list with editorial commentary on each.

What are the best alternatives to Rivet?

Top Rivet alternatives in DevOps are ranked by recent ship velocity. Browse the "Rivet alternatives" section above for the current picks, or visit /alternatives/rivet for the full list with editorial commentary on each.