Fly.io ditches its homemade JuiceFS filesystem for SBD: ext4 on a bucket as a block device
Fly.io Blog · rss · 2026-10-22
Fly.io rewrote Sprites' storage layer after their modified JuiceFS stack—three separately-durable ledgers of chunks, metadata, and checkpoints—proved fragile. A dogfooding harness ran 5,000 write/checkpoint/sleep/wake/restore cycles against 400 Sprites and found some permanently unable to checkpoint. The replacement, Sprites Block Device (SBD), presents the bucket as an NBD block device so ext4 runs directly on object storage: metadata lives beside its blocks, checkpoints become versioned volume snapshots, and restore costs about as much as a restart. Tests show orders-of-magnitude reliability gains; pre-10/6 Sprites can migrate.
More from coding & agent
- Ethan Mollick's new book charts 30 months of AI progress, from cyborg to conjurer work — rseroter · 2026-10-23
- OpenJet claims Qwen3.8-27B coding runs 1.9x faster than llama.cpp on one RTX 3090 — JeremyCMorgan · 2026-10-23
- Jensen Huang details Vera Rubin agentic stack: NVL72, MGX, CMX and RTX — rohanpaul_ai · 2026-10-23
- Building an autonomous SEO agent in Hermes with three skills: programmatic pages, Keywords Everywhere, DataForSEO — EXM7777 · 2026-10-23
- Building a sports betting AI agent with onchain execution and human approval by default: architecture and lessons — Dry-Comfortable-2678 · 2026-10-23
- Capy 0.5.0 lets Claude Pro/Max subscribers reuse their plan quota, adds OIDC cloud access — garrytan · 2026-10-23