Compare
Filament vs Sling
Side-by-side capabilities and benchmarks.
WALL TIME
114.8 s
9.2× faster
NYC Taxi, Postgres → Postgres
ROWS PER SECOND
2,288,144 rows
11.3× faster
TPC-H, Postgres → Postgres
CPU SECONDS
377.4 s
5.9× less
NYC Taxi, Postgres → Postgres
PEAK MEMORY
2.97 GiB
29.5× less
NYC Taxi, Postgres → Postgres
Sling is a single-binary CLI for moving data between databases, files, and APIs. It is quick to install and easy to script. The core is free, and parallelism, API sources, and change data capture are sold as paid tiers. Filament is an open-source replication engine with none of that gated. Parallel reads, checkpoints, change data capture, and verified writes ship in the free binary.
Verified benchmark comparison
Why Filament
Apache 2.0, open source
Self-hosted in full
Yes. One repository, no paid tier, nothing gated
Adding a new source
A YAML manifest for REST APIs, loaded at runtime with no rebuild. A Go driver for databases and other driver-based sources
Methodology
Configuration as run. Filament standalone image, 32 parallel readers, 25,000-row batches. Sling v1.5.20 free CLI in full-refresh mode with bulk loading and direct insert, one process per table. Sling holds the smallest memory footprint of any connector system in the cohort. On the eight-table TPC-H load, where table-level parallelism should have helped it, the gap widened from 9.2× to 11.3×.
Move data with Filament