Fly.io

Runs containers as lightweight VMs close to users, in many regions.

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Fly.io takes a container image of your app and runs it as virtual machines in data centres around the world, on hardware Fly.io operates itself. Requests reach the nearest running copy through a global Anycast network, so an app deployed to several regions answers users from close by.

The building block is the Fly Machine: a fast-starting VM (built on Firecracker) created from your image, with a REST API to create, start, stop and destroy it. A stopped Machine usually boots again in well under a second. Most apps use Fly Launch on top: fly launch scans your project and writes a fly.toml config (plus a Dockerfile for well-supported frameworks), fly deploy ships it, and fly scale changes CPU, RAM, Machine count and regions. Because it runs any Docker image, the language or framework doesn't matter.

What a small team gets: a choice of 17 regions across North America, Europe, Asia-Pacific, South America and Africa; autostop and autostart, so idle Machines stop and wake on the next request; a private WireGuard network between your apps; Fly Volumes for local NVMe storage; and Managed Postgres in most regions.

The trade-off is that you handle more of the reliability yourself. A volume lives on one physical server and attaches to one Machine, Fly.io doesn't replicate data between volumes, and with a single Machine and volume a hardware failure or a deploy means downtime and possible data loss. Fly recommends at least two Machines per app.

Where it fits

How Fly.io itself is built

9 tools, from its own code, website and Product Hunt page.

Who uses it

66 makers' products, each linked to the source that shows it, and 52 open-source projects that declare it in their code.

The maker says so 27Subprocessor list 5Seen on the website 45Declared in code 55How evidence is collected →
InfiniDeskInfiniDesk is a Mac menu bar app that switches between project-specific desktops, each s…

“Easy to convert local web application to a live one, with HTTPS.”

HostingMaker says so +1 · source ↗
OboeHigh performance experimentation platform

“Fly gives us the global edge deployment we need without the complexity of managing infrastructure across multiple regions. Their platform lets us focus on building Oboe while they handle the networking magic that keeps our experiments blazing fast worldwide.”

HostingMaker says so +1 · source ↗
KempoCustomized Code Playgrounds Powered by Sandpack

“Kempo is deployed on Fly.io which is extremely developer friendly and has made it so much easier to quickly deploy changes to both staging and production environments.”

HostingMaker says so +1 · source ↗
LaunchFastThe fastest and easiest way to build apps.

“Deployment is made on Fly. Its such a pleasure to work with! Generous free tier, simple pricing, easy scalability, zero-downtime deployments, and so much more! We've tried Vercel, AWS, and other cloud providers, but Fly.io is where its at!”

HostingMaker says so +1 · source ↗
SidenoteComment and live chat on any page of the internet

“Fly saved us a lot of time by simplifying the more cumbersome parts of getting an application deployed.”

HostingMaker says so +1 · source ↗
EXPOSEYour no-install & no-config tool to expose local services

“EXPOSE uses Fly.io to distribute the service worldwide. The internal network offered by Fly.io is just incredible.”

HostingMaker says so +1 · source ↗
Cure AIYour companion for evidence-based research.

“Fly’s setup process was smooth and intuitive. Hosting APIs globally with minimal configuration was a huge time-saver.”

HostingMaker says so · source ↗
PigAutomate Your Windows Computer with AI

“Machines on Fly made it easy to build SSL-secured proxies and backends for keeping cross-internet Pig automations safe and encrypted.”

HostingMaker says so · source ↗
MascotlyLogos are boring, Get a mascot that people actually remember

“Shoutout to @flyDev - Deploying Mascotly globally was seamless thanks to Fly.io. It made it super easy to get our backend up and running close to users with minimal config. Fast, reliable, and developer-friendly - couldn’t ask for more! 🚀🌍”

HostingMaker says so · source ↗

Open source: a project that declares Fly.io as a dependency in its public code — verifiable, but not necessarily a live product.

What makers say

21 makers on why they use Fly.io, in their own words on Product Hunt.

Fly gives us the global edge deployment we need without the complexity of managing infrastructure across multiple regions. Their platform lets us focus on building Oboe while they handle the networking magic that keeps our experiments blazing fast worldwide.
OboeSep 2026 ↗
Shoutout to @flyDev - Deploying Mascotly globally was seamless thanks to Fly.io. It made it super easy to get our backend up and running close to users with minimal config. Fast, reliable, and developer-friendly - couldn’t ask for more! 🚀🌍
MascotlySep 2026 ↗
Machines on Fly made it easy to build SSL-secured proxies and backends for keeping cross-internet Pig automations safe and encrypted.
PigSep 2026 ↗
Fly’s setup process was smooth and intuitive. Hosting APIs globally with minimal configuration was a huge time-saver.
Cure AISep 2026 ↗
For $15/month, I'm able to decode 15k/sec ADSB messaging, serialize it, and serve to 10,000 concurrent users!
Flight FollowerSep 2026 ↗

Loved and watch-outs

Themes that recur in makers' words and Hacker News comments, each linked to what it summarises, with how Product Hunt tags its reviews.

Most loved
  • Apps deploy close to users around the world with minimal configuration. PH
  • The CLI makes deploys and scaling a single command. PH
  • Pricing is simple and predictable, with small containers costing very little. HNHN 2PH
  • The free tier is generous for side projects. PHHNHN 2
Watch-outs
  • Its unmanaged Postgres needs manual recovery when nodes fail or run out of memory. HNHN 2
  • Repeated major outages undermine confidence in its stability. HN
On Product Hunt 5.0★ · 27 reviews
easy deployment 5developer friendly 3CLI 2easy scalability 2free tier 2simple pricing 2
Read the reviews on Product Hunt ↗

Reliability and open issues

Incidents on its status page25+ in the last 90 days, 11 major · 25+ in the last year
  • minor Delayed ingestion of app logs Oct 2026
  • none GRU Networking Issues Sep 2026
  • critical Network outage in AMS region Sep 2026
From its own status page, 2026-10-02. Vendors decide what they post; one page can cover several products.

Who switches

Public pull requests on GitHub since Oct 2024 whose title says "X to Y" — real code changes moving a project from one tool to another, by developers in general. Open a row to see the pull requests.

Render → Fly.io15 PRs
Railway → Fly.io12 PRs
Vercel → Fly.io11 PRs
Cloudflare → Fly.io6 PRs
Amazon Web Services → Fly.io4 PRs
Fly.io → Render21 PRs
Fly.io → Railway15 PRs
Fly.io → Cloudflare10 PRs
Fly.io → Vercel7 PRs
Fly.io → Amazon Web Services6 PRs

Alternatives to Fly.io

All alternatives by situation →

Questions makers ask about Fly.io

What does the free trial include, and what happens when it ends?

The trial gives 2 hours of total Machine runtime or 7 days, whichever comes first, with up to 10 Machines; trial Machines stop automatically after 5 minutes of running. When it runs out, your apps stop until you add a payment method. source ↗

Which regions can I deploy to?

17 regions, including several in the US, Toronto, São Paulo, Amsterdam, Frankfurt, London, Paris, Stockholm, Johannesburg, Tokyo, Singapore and Sydney. Machines and volumes stay in the region they were created in, and Managed Postgres is available in most but not all regions. source ↗

Can my app scale to zero when nobody is using it?

Yes. With autostop and autostart in fly.toml, the Fly Proxy stops or suspends idle Machines and starts them again when requests arrive. You aren't charged for the CPU and RAM of stopped Machines. source ↗

Is a Fly Volume safe for my database?

Only with care. A volume is a slice of an NVMe drive on one server, attached to one Machine, with no automatic replication; Fly takes daily snapshots (kept 5 days by default) but says they shouldn't be your main backup. Run at least two Machines with volumes and replicate the data yourself, or use Managed Postgres. source ↗

Do I need Docker or a Dockerfile to deploy?

Fly runs container images, but fly launch can scan your source and produce a Dockerfile for frameworks it knows well; otherwise point it at your own Dockerfile or a prebuilt image. source ↗

Is Fly.io SOC 2 compliant, and will it sign a HIPAA BAA?

Fly.io is SOC 2 Type 2 audited and will sign BAAs for healthcare apps. Apps run in Firecracker VMs with no shared kernel, and traffic between hosts goes over WireGuard. source ↗

Is Fly.io free?

No permanent free tier; paid use starts at $1.94/mo (shared-cpu-1x). source ↗

Is Fly.io open source or self-hostable?

Not open source, and hosted only.

Can AI coding agents work with Fly.io?

It serves an llms.txt docs index.

Who uses Fly.io?

66 makers' products we track, each with a source, and 52 open-source projects declare it in their code. source ↗