Persistent Storage and Fast Remote Builds

If you’ve been keeping up with us at Fly, you may be picking up on a bit of a narrative with us. Fly launched, in the long-long-ago, with a somewhat narrow use case. We took containers from our customers and transmogrified them into fleets of Fire...

By Jerome Gravel-Niquet

4 min Read

The Tokio Upgrade from 0.2 to 1.x

At Fly.io, we run a Rust-based load-balancer which handles almost all of our traffic. It stands on the shoulders of Tokio and Hyper. When the Tokio team announced 0.3 and then 1.0, we figured we'd have to upgrade sooner than later to access relate...

By Thomas Ptacek

10 min Read

You should know about Server-Side Request Forgery

This is a post about the most dangerous vulnerability most web applications face, one step that we took at Fly to mitigate it, and how you can do the same. Server-side request forgery (SSRF) is application security jargon for “attackers can get ...

By Dj Walker-Morgan

3 min Read

The January 2021 Fly ChangeLog

If you missed 2020, lucky you, to get you all caught up, here's our Previously On Fly segment. Caught up? Good. And now here is the Fly ChangeLog, covering the end of December 2020 to January 2021. 6PN Networking and IPv6 WireGuard VPNsLet your a...

By Dj Walker-Morgan

2 min Read

Fly In 2020 - A year in features (and articles)

TL:DR; Launch, Turboku, Custom Domains, Scaling, One-Click Apps, Persistent Storage, Private Networking and Wireguard VPNs. Fly's had an unprecedented year, along with everyone else. For us, it was bringing our Application Platform to the world, a...

By Dj Walker-Morgan

<1 min Read

How to build a global message service with NATS

There are actually two examples that make up this example. One example is a Websocket-based chat that relays its messages through that NATS cluster. The other part is that NATS cluster, configured as a global messaging cluster that you can install...

By Thomas Ptacek

16 min Read

Building clusters with serf, my new favorite thing

Assume for a second we’d like to see what happens when a web page loads in a browser in Singapore. Easy enough; Fly.io will take a container image you throw at it, transform it into a Firecracker VM, and run it in Singapore. Getting Up And Runnin...

By Dj Walker-Morgan

2 min Read

Get fly with your Fly command line

The command... It started off as flyctl but we kept being asked when would the command become fly. "Why not both?" we said and now, on most platforms, you can use flyctl or fly interchangeably. Boom! Three keystrokes saved! The current app... ...

By Michael Dwan

4 min Read

Graceful VM exits, some dials

Fly apps are typically fast to boot, and it's relatively easy to boot new VMs. We start them up, do some health checks, and then add them to our load balancer and DNS service discovery. But what comes up must go down. We shut VMs down for any numb...

By Thomas Ptacek

11 min Read

IPv6 WireGuard Peering

They say that when you’re starting a product company, it’s a better plan to chase down something a bunch of people will really love a lot than it is to try to build something that everyone will just like a little bit. So when Fly.io launched, it h...

By Kurt Mackey

5 min Read

New VMs: more RAM, extra CPU, and a dollar menu

We first showed Fly.io VMs to developers in early 2020. They were most interested in running CPU intensive apps doing image processing, machine learning predictions, and even video transcoding (despite what were, until recently, offensive bandwidt...

By Thomas Ptacek

6 min Read

Incoming! 6PN Private Networks

More often than not, modern applications are really ensembles of cooperating services, running independently and transacting with each other over the network. At Fly.io, we’d like it to be not just possible to express these kinds of applications, ...