Why Walsync?

Why Walsync?

Walsync was inspired by Litestream, the excellent SQLite replication tool. While Litestream pioneered WAL-based replication, Walsync addresses key scalability challenges for multi-database deployments.

Memory Efficiency at Scale

Both Litestream (v0.5+) and Walsync support multi-database sync from a single process. Walsync’s Rust implementation has a smaller memory footprint:

• Walsync: ~12 MB baseline (constant regardless of database count)
• Litestream: ~33 MB baseline

For resource-constrained environments (512MB VMs, containers, edge deployments), this 21 MB difference matters. See benchmarks for detailed measurements.

Walsync’s Multi-Database Architecture

A single Walsync process handles:

• Shared S3 client with connection pooling
• Efficient file watching across all databases
• Consolidated configuration
• Minimal per-database overhead

When to Use Walsync

Choose Walsync when:

• You have multiple SQLite databases to sync
• Memory efficiency matters (containers, edge deployments)
• You need cryptographic data integrity verification
• You want a unified configuration for many databases

Choose Litestream when:

• You have a single database
• You need mature, battle-tested replication
• Point-in-time recovery granularity is critical

Design Philosophy

Walsync is built on these principles:

1. Efficiency first - Minimal resource usage, even at scale
2. Correctness always - SHA256 checksums verify every sync
3. Simple operations - One binary, one process, many databases
4. Cloud-native - Built for S3-compatible storage (AWS, Tigris, R2, MinIO)