Litestream VFS

Source: fly.io Date: 2026-01-15 URL: https://fly.io/blog/litestream-vfs/

Summary

Engineering writeup introducing Litestream’s read-only VFS plugin, which enables point-in-time recovery queries directly against S3-backed SQLite without downloading the full database locally. The approach uses LTX compaction, hierarchical backups (daily → hourly → 30-second), indexed page lookup via S3 Range headers, and a PRAGMA litestream_time interface to travel to arbitrary past moments in a running database.

Implications

Edge deployment economics / local-first architecture. This capability closes a significant gap for SQLite-on-S3 deployments: historical queries without a restore step. Combined with Litestream’s existing streaming replication, the VFS mode makes SQLite a credible operational database for distributed edge environments — not just for durability, but for debugging and auditing. This is load-bearing infrastructure for the Sprites + Litestream storage stack fly.io is assembling. It also reinforces the broader local-first trend (SQLite, single-binary, no cloud dependency) that Ellis tracks: the question shifts from “why SQLite?” to “why not?”