DEXTR is a deterministic execution runtime for Linux designed to eliminate non-deterministic behavior in system resource management. The system is implemented in Rust using a no_std configuration with full exclusion of dynamic memory allocation (alloc-free), ensuring predictable execution and eliminating runtime allocator-related uncertainty. DEXTR follows a strict architectural pipeline: Telemetry → Analyzer → Policy → Validator → Executor Key properties: - Deterministic execution model- Hard real-time compatibility- Zero-allocation steady state- Strict separation between decision logic and execution Validation results: - Iterations: 1000- Average latency: 2798 µs- p99 latency: 3986 µs- Worst-case latency: 4618 µs- Variation: 9.42% All hard real-time criteria are satisfied. The system is positioned as a foundational layer for deterministic control in Linux environments and is intended for further development, research collaboration, and integration into critical systems.