FTL is a new operating system for clouds where developers build their own OS as a library. The userspace OS design makes it easy to add features, debug, and upgrade the OS safely.
The FTL kernel isolates containers (userspace OS instances) better than existing monolithic kernels, with a hypervisor-like interface based on lightweight hardware-based isolation in user mode — no bare-metal machines required.
FTL is compatible with Linux binaries. The Rust-based HTTP server serving the FTL website is a Linux application running on FTL. Developers can also run unikernel-like specialized applications without POSIX abstractions.
Each container runs a userspace OS implemented as a shared library covering Linux process concepts, VFS, and TCP/IP. The FTL kernel provides a minimal interface for implementing Linux system calls in userspace, similar to a hypervisor.
FTL combines microkernel flexibility and security with monolithic kernel performance. Goal: make lightweight containers as secure as VMs and unlock new OS-level abilities without sacrificing performance.
Roadmap milestones: September 2026 — simple Linux HTTP server on FTL (v0.0.1 released); October 2026 — async Rust apps support with Linux threads and epoll (v0.1.0 released); November 2026 — filesystem; December 2026 — Node.js/Go support; January 2027 — SMP, container images, 64-bit Arm support.