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We cut @nodejs memory in half with a one-line Docker image swap. No code changes. No new APIs. Just smaller heaps. Here's what happened when we tested pointer compression on real workloads 🧵

V8 has had pointer compression since 2020 (Chrome uses it!), but Node.js couldn't enable it — because all worker threads shared a single 4GB memory cage. @Cloudflare sponsored @Igalia to fix it in V8 with a new feature called IsolateGroups.

The fix: each isolate now gets its own 4GB cage. Your main thread gets 4GB, each worker gets 4GB. The old process-wide limit is gone. The Node.js integration by @jasnell is 62 lines across 8 files.

@platformatic built node-caged, our Node.js 25 Docker image with pointer compression enabled: and benchmarked it on AWS EKS with a real Next.js e-commerce app (10K cards, 100K listings, SSR, search, simulated DB delays). hub.docker.com/r/platformat...

Results: → ~50% memory reduction → 2-4% average latency overhead → p99 and max latency actually improved Smaller heap = shorter GC pauses. For most teams, this is a no-brainer.

Try it, it's one line change: FROM platformatic/node-caged:25-slim Same Node.js, same APIs. Just smaller heaps. Keep in mind that this is an experimental feature.

Huge thanks to James Snell, Andy Wingo, Joyee Cheung, Dmitry Bezhetskov, Igalia, and Cloudflare for making this happen. Open source collaboration at its best. Full write-up with benchmarks and limitations of this approach 👇 blog.platformatic.dev/we-cut-nodej...