Our auto-tiering feature allows you to manage a massive database (e.g., 5TB+) primarily on cheap, durable object storage (like S3), which is already built for cross-AZ replication and is up to 3x cheaper than traditional cloud block storage (EBS).

We use local NVMe SSDs (200K+ IOPS) purely as a high-performance cache layer to accelerate read access. Hot and cold data are automatically swapped across memory, SSD, and object storage tiers based on access frequency, ensuring high performance (up to 100x faster than archive solutions)

EloqDoc follows a fundamentally different architectural path. Instead of executing in Postgres, we leverage the existing MongoDB parser and executor to ensure maximum compatibility. Our main contribution is to replace the single-writer WiredTiger storage engine entirely with Data Substrate.

The Data Substrate is an abstract layer built specifically to handle distributed database fundamentals: scalable buffer pooling, concurrency control, durability, elasticity, and fault tolerance. You can read more: https://www.eloqdata.com/blog/2025/07/14/technology

This architectural choice is what enables EloqDoc to deliver features that Postgres-based solutions cannot easily match, including: full compatibility, native Multi-Writer capability, Object Storage First and extremely low-latency distributed transactions.

[1] https://news.ycombinator.com/item?id=44937978