Websites and hosting decision
Fly.io
A small team can reproduce basic container hosting and a CLI, but Fly.io's durable advantage is its global low-latency infrastructure, boot-time guarantees, checkpointed 'Sprite' primitives, and commercial support—capabilities impractical to replicate for a single developer or small team.
Visit website↗Open-source builds that already do this
Every project below is open source and already does this job today. Fork one, self-host it, or take the parts you need — the build prompt further down assumes an empty file, and this is the shortcut past that. Licences differ; check the one on each card before you ship.
Code Fly.io publishes itself
Not a way out of the subscription — these are the vendor’s own repositories. Worth a look for how they build, and for anything you would have to integrate with.
- superfly/litefs★4,857 GitHub starsApache-2.0FUSE-based file system for replicating SQLite databases across a cluster of machines↗
- superfly/corrosion★1,821 GitHub starsApache-2.0Gossip-based service discovery (and more) for large distributed systems.↗
- superfly/flyctl★1,689 GitHub starsApache-2.0Command line tools for fly.io services↗
- superfly/fly★991 GitHub starsDeploy app servers close to your users. Package your app as a Docker image, and launch it in 17 cities with one simple CLI.↗
What a replacement has to do
- Deploy and run containerized apps (machines) with attached persistent volumes, public HTTP routing with TLS, and autoscaling.
What it still won’t have
- Global multi-region edge footprint and low-latency boot/launch guarantees
- Built-in Sprite checkpointing / sleep-wake durable filesystem semantics
- Prebuilt connectors and centralized credential gateway for services
- Commercial SLA and vendor support
What remains hard
- Infrastructure at scale
18+ Regions worldwide
- Infrastructure at scale
<1 second Machine boot time
- Infrastructure at scale
99.9% Uptime SLA
First-year cost
Keep paying
Paying is—cheaper in year one.
On cash alone, building overtakes the subscription at 3 seats.
Money you would actually spend
Time you would spend
—
What you would spend
What we assumed
The verdict above measures whether you could build it. This one is only about money.
Runnable build prompt
Build a minimal self-hosted alternative to Fly.io using: Terraform + DigitalOcean (or AWS) VMs, Docker, a small orchestration layer in Go or Python, Postgres for metadata, and S3-compatible object storage. In scope: a CLI to launch a named app (build/push a container image), API endpoints to create/start/stop machine instances, attach/detach persistent block storage volumes, a simple HTTPS router with TLS (Let's Encrypt) and custom domain provisioning, health checks, and basic autoscaling based on CPU or request metrics. Out of scope: multi-region global CDN, advanced checkpointing/instant snapshots across many regions, enterprise SLAs, and curated connectors. Include error handling, input validation, and automated tests for the CLI and API.
How we checked
How the score was reached
- Pay verdict base20
- An open-source build was found+5
- 4 cited sources+3
- Price verified on pricing page+3
- Hard moats found in the evidence-3
- Evidence score28
The base comes from the verdict. Everything under it is a check that either happened or did not, and each one is a fact frozen in this record rather than a judgement made at render time — so the same evidence always produces the same number.
How scoring works →Cited sources · 4
Every page the run actually retrieved.
- official productFly.io
- official pricingPricing · Fly
- official docsFly.io developer documentation
- open sourceOpenNebula/one
Integrity checks
What held up, and what did not.
