Architecture
QuantumRT is built around one core invention. Everything else follows from it.
Precise Scheduling
Most RTOSes use a periodic tick which is a fixed-rate timer interrupt that wakes the processor hundreds or thousands of times per second to check whether anything needs to run. Most of the time, nothing does.
QuantumRT's scheduler instead programs the hardware timer to fire at the next scheduled event.
Predictable latency
Tick-based schedulers introduce jitter where events don't fire when they are due, they fire at the next tick boundary. With Precise Scheduling, the timer fires at the exact deadline every time. Scheduling jitter is eliminated, so worst-case response time is consistent.
Lower power consumption
Tick-based kernels wake the CPU at a fixed rate regardless of whether there is work to do. Precise Scheduling only wakes the CPU when an event is actually due. The CPU spends more time in deep sleep but not because of dedicated power management code, but as a direct consequence of scheduling correctly.
How Precise Scheduling works
Tick-based scheduling is a design compromise. We removed it.
Traditional RTOSes typically generate a periodic timer interrupt at a fixed rate of 100 Hz to 10 kHz. Every tick, the kernel checks whether anything needs to run. Most of the time, nothing does. QuantumRT's scheduler instead programs the hardware timer to fire precisely at the next scheduled event, and no sooner.
Timer fires only on actual events
The hardware timer is reprogrammed after each event to fire at exactly the next deadline. No periodic overhead, no jitter accumulation from tick rounding.
Timing precision is hardware-limited, not software-limited
With tick-based scheduling, timing resolution is bounded by tick frequency. With Precise Scheduling, it is bounded only by your hardware timer's resolution.
Tick-count compatibility API
Migrating from a tick-based kernel? QuantumRT exposes a tick-count API so legacy code that reads tick counters continues to work without changes.
Precise Scheduling
Tick-Based Scheduling*
* QuantumRT does not support Tick-Based Scheduling and exclusively uses Precise Scheduling.
FEATURES
A focused, auditable kernel with POSIX-native APIs, a complete set of synchronization primitives, and optional memory protection.
POSIX Native
QuantumRT implements a subset of POSIX.1-2024 at the kernel level. Not a POSIX compatibility wrapper layered on top of a proprietary API but a native interface. Code written for Linux using pthreads, mutexes, semaphores, message queues, and timers ports to QuantumRT with minimal modification and without carrying a full OS. See the POSIX compliance matrix →
Memory Protection
​A runaway thread should not be able to corrupt the kernel, scribble over another thread's stack, or toggle hardware it has no business touching. When your target includes an MPU, QuantumRT can be configured to enforce strict hardware-backed boundaries between every layer of the system.
Supported Architectures
Support across ARM Cortex-M variants and RISC-V targets. Full source code is delivered with every license.
Industrial automation
PLCs, motion controllers, and sensor nodes where microsecond timing directly affects output quality and machine safety.
Robotics
Real-time control loops for servo systems, actuators, and sensor fusion pipelines that require predictable, jitter-free scheduling.
IoT & wearables
Battery-constrained connected devices that need the communication stack, sensor polling, and power management to co-exist without sacrificing response time.
BUILT FOR
Where QuantumRT fits
Licensing
One license. Ship everything.
QuantumRT is sold as a flat-fee commercial license. No per-unit royalties, no per-developer seat fees, no annual renewal requirements to keep shipping your product.
Truly royalty-free
Unit volume does not affect your licensing cost. Ship 10 units or 10 million.
Full source code included
Inspect every line, audit the scheduler, port to new hardware targets without asking permission.
Direct developer support
Issues are handled by the authors.
No open-source obligations
Commercial license means no GPL copyleft requirements touching your application code.
Single flat fee
Pay once per product, not per unit, per seat, or per year.
Predictable cost at scale
Unlike enterprise RTOS vendors that charge $10K–$20K per developer seat, QuantumRT's flat structure keeps costs calculable from day one.
Get Started
Talk to the team
Reach out to the team for licensing, technical questions, or evaluation.
Get Started
[email protected]
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