Porting NASA's Core Flight System (cFS) to our Custom OS — cfs-on-exploidus

Sun, 01 Nov 2026 17:34:45 +0000

Hi everyone,

Over the past few weeks, I’ve been working on an exciting systems engineering challenge: porting NASA's Core Flight System (cFS) natively onto our custom microkernel platform, Exploidus OS.

For context, cFS is NASA’s open-source, mission-critical flight software framework powering prestigious space missions—including Artemis lunar payloads, lunar landers, smallsats, and deep-space instruments.

Historically, cFS runs on traditional platforms like Linux, VxWorks, or RTEMS. Our goal was to push the architectural boundaries further:

Deploy NASA cFS on a capability-hardened, memory-safe execution layer without modifying a single line of portable cFS core code.

This project is called cfs-on-exploidus.

The Technical Challenge: OSAL & PSP Abstractions

cFS is architected around the Operating System Abstraction Layer (OSAL) and the Platform Support Package (PSP). The framework never invokes raw host syscalls directly; every task creation, mutex acquisition, queue transaction, and timer tick passes through the OSAL interface.

To bring cFS to Exploidus OS, we engineered:

Native OSAL Implementation: Mapped standard cFS POSIX/RTOS abstractions directly onto Exploidus OS microkernel primitives—achieving deterministic task scheduling, non-blocking inter-task queues, and clean lifecycle management.
Capability-Hardened Boundaries: Standard monolithic architectures suffer when an unprivileged payload task crashes or behaves adversarially. Exploidus leverages microkernel capability tokens to isolate critical spacecraft effector lines and execution contexts right at the hardware boundary.
Pure Core Portability: The Core Flight Executive (cFE) services—Executive Services (ES), Software Bus (SB Core), Event Services (EVS), and Table Services (TBL)—build and execute cleanly in userspace with zero core patches.

Current Status & Open Source
Release v0.3.0 is now live and stable.
The project has been shared in the official NASA cFS community discussions as a reference architecture.
Source code is fully open-source on GitHub:
Repository: https://github.com/Exploidus/cfs-on-exploidus

Venturing into kernel development, low-level OS primitives, and aerospace flight software is a long and challenging road, but seeing NASA's flight stack boot on custom-engineered OS foundations makes every bit of debugging worth it.

If you are into low-level systems programming, OS development, or flight software, I would love to hear your thoughts, feedback, or critiques!

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Porting NASA's Core Flight System (cFS) to our Custom OS — cfs-on-exploidus