Kolmos is a cloud database engine built for PostgreSQL, MySQL, and MongoDB workloads. It combines self-compressing storage, columnar architecture, and multi-wire compatibility to reduce database storage and cloud infrastructure costs.

Which database wire protocols does Kolmos support?

Kolmos natively supports PostgreSQL (port 5432), MySQL (port 3306), and MongoDB (port 27017) wire protocols. Standard drivers, ORMs (Prisma, Drizzle, SQLAlchemy, Hibernate), and database clients connect seamlessly with zero application code changes.

How does Kolmos reduce cloud database storage costs?

Kolmos uses an autonomous Explanation Ladder that mines Minimum Description Length (MDL) formulas and prototype clusters to compress data 1.66×–2.12× smaller than Parquet-zstd. It stores files directly on Cloudflare R2 object storage ($0.015/GB/mo) with zero data egress fees, cutting overall cloud database storage bills by 10× to 40×.

Is Kolmos data recovery 100% lossless?

Yes. Kolmos guarantees 100% mathematical fidelity via Invariant #1: decode(encode(x)) == x across all SQL and BSON data types. Every row decodes bit-perfectly with zero precision drift.

How does Kolmos execute fast analytical queries on cloud object storage?

Kolmos embeds min/max statistics and Bloom filters into segment headers. Using Apache DataFusion vectorized execution and predicate pushdown, the engine prunes irrelevant segments and streams zero-copy Apache Arrow memory buffers without downloading unneeded data.

What prevents vendor lock-in with Kolmos storage formats?

Every Kolmos segment footer pins an open, self-contained WASM decoder covenant executed in an isolated Wasmtime sandbox. This guarantees your database files remain readable perpetually decades later without requiring proprietary server runtimes.

Docs/Operations & Optimization

Storage & Cold Storage Setup

Configuring Cloudflare R2 / AWS S3 offloading, TTL workers, and background vacuuming.

Last Updated: August 2026

Setting Up Postgres & MongoDB Cold Storage on Cloudflare R2

Offload historical database segments to Cloudflare R2 to pay $0 for egress and $0.015/GB/month for storage:

bashKOLMOS Reference

# Environment configuration for R2 Object Storage offloading:
export KOLMOS_STORAGE_TIER=hybrid
export KOLMOS_S3_ENDPOINT=https://<account-id>.r2.cloudflarestorage.com
export KOLMOS_S3_BUCKET=kolmos-cold-storage
export KOLMOS_S3_ACCESS_KEY_ID=<your-access-key>
export KOLMOS_S3_SECRET_ACCESS_KEY=<your-secret-key>

# Run KOLMOS with cold storage offloading enabled:
./kolmos serve --root ./data --cold-tier-enabled true

Background Vacuuming & TTL Workers

KOLMOS automatically runs two background maintenance processes: - **Vacuum Worker:** Runs every 10 minutes to compact deleted tombstone rows and reclaim disk space. - **TTL Worker:** Scans collections with `expireAfterSeconds` index specs every 60 seconds to purge expired documents.

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