Computers for agents — real infrastructure for AI agents and the apps they build
HQ: Chicago, IL (distributed team; SF presence) | Founded: 2017 | Employees: ~100-120 | Stage: Series D ($25M, July 2026); ~$136M total raised | Website: https://fly.io
Fly.io's origin story runs through Kurt Mackey's earlier company, Compose, a database-as-a-service built on rented clouds and sold to IBM in 2017. Having watched customers fight hyperscaler complexity and latency, Mackey founded Fly (initially 'Docket') on a contrarian premise: instead of reselling AWS, run apps on your own global fleet of physical servers, close to users. The company spent its first years building that fleet and the software to manage it — including an early, ill-fated serverless product that failed commercially but taught the team what developers actually needed: real machines with real disks, not clever abstractions.
The modern Fly.io is a compute platform built on Firecracker, AWS's open-source microVM technology, running on Fly-owned bare metal in dozens of locations worldwide. Developers deploy with a single 'fly deploy' command or a Dockerfile; the platform places their VMs near their users, attaches persistent volumes, wires private networking (Fly Machines, WireGuard-based private networks, Anycast routing), and scales instances from zero to millions. The pitch: 'real computers' — durable, stateful, fast — without a Kubernetes cluster or a cloud bill for idle capacity. Pricing is usage-based per VM per second.
The 2026 chapter repositioned the company around AI agents. As agents moved from chat to building and operating software, they needed execution environments that persist: durable storage, secure connections to other systems, and elastic scale to production traffic. Fly.io's answer is 'computers for agents' — the same platform reframed for a user that isn't human. The numbers behind the pivot: strongest quarter in company history (July 2026), 37,000+ customers with 8,000+ agent-native, ~12x year-over-year growth in revenue from the largest agent-native customers, and agent-native companies now roughly two-thirds of revenue among Fly's largest customers. Firecrawl, Kilocode, and Plastic Labs are public references; Phonic's co-founder credited Fly as 'the only one that treated long-running, stateful compute as a first-class primitive.'
Leadership scaled with the shift. In July 2026, Scott Johnston — former CEO of Docker and veteran of Puppet, Loudcloud, and Netscape — joined as CEO; founder Kurt Mackey moved to the board and an advisory role focused on long-term technical vision. A $25M Series D co-led by Dell Technologies Capital and Intel Capital, with a16z, EQT, Geodesic, and YC participating, funds the category build; Martin Casado (a16z) and Daniel Docter (Dell TC) joined the board, with Casado framing the thesis: 'for the first time [the primary user of infrastructure] isn't necessarily a person. That changes what a computer has to look like.'
Fly.io spent nearly a decade building something unfashionable — a global fleet of servers it owns, running apps in Firecracker microVMs close to users — because its founders believed developers should get the power of a cloud without the ceremony of one. The 2026 twist is that its strangest structural choice became its biggest AI asset: agents that 'build, operate, and deploy software' need computers that persist. Durable disks, real networking, millions of scalable instances — not disposable sandboxes that forget everything between sessions.
The market moved first. Fly.io just closed its strongest quarter ever, driven almost entirely by agent workloads: 8,000+ of its 37,000+ customers are agent-native, agent-native revenue among its largest customers grew ~12x in twelve months, and such companies now generate about two-thirds of revenue among its biggest accounts. Firecrawl, Kilocode, and Plastic Labs run production agent systems on Fly; Phonic chose it because it 'treated long-running, stateful compute as a first-class primitive.'
The company also professionalized its leadership: Docker's former CEO Scott Johnston took over as CEO in July 2026, with founder Kurt Mackey moving to the board and an advisory role, as $25M from Dell Technologies Capital and Intel Capital funds the 'computers for agents' category. The strategic risk is obvious — hyperscalers and every agent-platform startup want the same workload — but Fly's nine years of stateful compute infrastructure is a real head start, and its case that 'the primary user of infrastructure is no longer a person' is increasingly the industry's own conclusion.
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