What's FTL?
- You can build your own OS as a library. This userspace OS scheme makes it uncomplicated to add features, debug, upgrade the OS safely, as if penning applications.
- FTL kernel isolates containers (userspace OS instances) improved than existing massive kernels, alongside a hypervisor-like interface according to a lightweight hardware-based isolation (user mode). You don't need bare-metal machines.
- FTL is compatible alongside Linux binaries. For example, the Rust-based HTTP server serving this website is a Linux use operating on FTL. You can additionally run Unikernel-like specialized applications without POSIX abstractions.
How it works
Each receptacle runs a userspace OS. It is a shared archive which implements most of OS concepts specified as Linux process, VFS, and TCP/IP. FTL kernel provides a minimal interface to execute Linux scheme calls in userspace, fair akin a hypervisor.
FTL combines the finest of microkernels (flexible & secure) and massive kernels (performant & simple). Our goal is to make lightweight containers as safe as VMs, and unlock new OS-level abilities in applications, without sacrificing performance:
FTL Linux ┌────────────────────────────────┐ ┌────────────────────────────────┐ │┏━━━━━━━━━━━━━┓ ┏━━━━━━━━━━━━━┓│ │┏━━━━━━━━━━━━━┓ ┏━━━━━━━━━━━━━┓│ │┃ ┃ ┃ ┃│ │┃ ┃ ┃ ┃│ │┃ Linux ┃ ┃ Linux ┃│ │┃ Linux ┃ ┃ Linux ┃│ │┃ Process ┃ ┃ Process ┃│ │┃ Process ┃ ┃ Process ┃│ │┃ ┃ ┃ ┃│ │┃ ┃ ┃ ┃│ │┃╌╌╌╌╌ Linux scheme calls ╌╌╌╌╌┃│ │┗━━━━━━━━━━━━━┛ ┗━━━━━━━━━━━━━┛│ │┃ ┃│ └────────────────────────────────┘ │┃ Userspace OS ┃│ ╌╌╌╌╌╌╌╌ Linux's interface ╌╌╌╌╌╌╌ │┃ (Process, VFS, TCP, ...) ┃│ ╔════════════════════════════════╗ │┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛│ ║ ║ └────────────────────────────────┘ ║ Linux Kernel ║ ╌╌╌╌╌╌╌ minimal interface ╌╌╌╌╌╌╌╌ ║ ║ ╔════════════════════════════════╗ ║ process, fork/exec, memory, ║ ║ FTL Kernel ║ ║ signals, TCP/IP, /proc, ║ ║ vCPU, memory, drivers, ... ║ ║ /dev, drivers ... ║ ╚════════════════════════════════╝ ╚════════════════════════════════╝
Userspace OS scheme additionally enables you to broaden most of Linux kernel features without kernel/eBPF programming. You can add printfs, use safety updates, and add new features quickly and safely. In FTL, OS is fair a library. Read more.
Roadmap
- September 2026: Run a uncomplicated Linux HTTP server on FTL (released in v0.0.1 ✅)
- October 2026: Async Rust apps assistance - Linux threads, epoll, ... (released in v0.1.0 ✅)
- November 2026: Filesystem
- December 2026: Node.js / Go support
- January 2027: SMP, receptacle images, 64-bit Arm support
