Fly.io vs Railway

• Fly-io offers a wider RAM ceiling of 16 GB compared to Railway's 8 GB limit, making the former better suited for memory-hungry Postgres indexes.
• Disk storage overages are more economical on Fly-io at $0.15/GB, whereas Railway charges a steeper $0.25/GB for additional persistent volume space.
• Network egress is significantly cheaper on Fly-io at $0.02/GB, while Railway imposes a premium of $0.10/GB on data transfer.
• Railway caps included storage at a meager 10 GB across their database offerings, while Fly-io scales up to 160 GB, providing more breathing room for large datasets without triggering immediate overage fees.

Fly-io operates on a model that favors developers building on Firecracker micro-VMs, allowing for more granular control over the underlying hardware footprint. Their pricing structure is optimized for high-volume data egress, which is typical if you are running heavy analytical queries or frequent database dumps. While Railway provides a simpler interface that appeals to teams moving quickly with minimal configuration, their storage and egress costs accumulate rapidly once you exceed their base tiers. The hardware disparity is also notable; while Railway allows for up to 8 vCPU cores, the constrained storage and higher per-GB costs create a financial ceiling for data-intensive applications that Fly-io simply does not enforce at the same scale.

Choosing between these two depends on your storage trajectory and egress patterns. Railway simplifies the initial setup for small-to-mid-sized relational databases, but the $0.10/GB egress rate and $0.25/GB storage penalty make it less viable for scaling beyond modest production workloads. Fly-io remains the more cost-effective choice for developers who expect their database size or traffic volume to grow consistently over time, as their lower overage rates protect the monthly bill from sudden spikes.