Compilers and operating systems, written from scratch. No LLVM, no GCC.
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My current work. A microkernel with a frozen surface of three syscalls, a capability-based security model, and three native compilers — all written in Rust from scratch.
It boots on an AMD Ryzen 5 5600X, not in an emulator, and occupies 5.4 MiB of 14.8 GiB of RAM.
| Kernel | 3 syscalls, capabilities, preemptive scheduling, Ring 0 ↔ Ring 3, demand paging, copy-on-write |
| Drivers | USB keyboard (xHCI + HID), AHCI/SATA, GPT, FAT32 — all written from scratch |
| Compilers | COBOL, C and Ada, each emitting x86-64 machine code directly to a native binary format |
| Filesystem | Content-addressed, copy-on-write, BLAKE3 — writing is committing |
Exact decimal arithmetic: 19.99 × 3 = 59.97, computed in integer scale
and confirmed on silicon. That is the primitive banking software is built on,
and it is why COBOL never died.
▶ Video: booting and running a banking batch job
The source is private under a source-available commercial license. Documentation, examples and binaries are public.
This is the part I care most about, and it is unusual enough to state plainly.
The compilers are tested by a conformance matrix that executes the emitted
machine code and checks the real output — not by comparing against
hand-written byte strings. An IF that fails to branch looks identical to one
that works in a byte dump; the only way to tell them apart is to run them.
And the order of authority is written down and enforced:
- The real CPU
- The specification document
- The emulator
When the emulator and the hardware disagree, the emulator gets fixed. That
rule caught a broken lea [rip+disp] that passed green in simulation and
would have read garbage on real silicon.
Features that aren't implemented are rejected with a reason, never stubbed to look like they work.
| Project | What it is |
|---|---|
| ADead-BIB | C/C++ compiler emitting x86-64 directly. Own SSA IR, PE and ELF output, no external linker. |
| PyDead-BIB | Compiles a subset of Python to native x86-64 — no CPython, no LLVM, no runtime in the output binary. |
| REACTOR | Vulkan framework with a visual node editor. Small executables, no heap allocation at startup. |
| EPICX | DirectX 12 framework. |
| ASM-BIB | x86-64 assembler. |
These are research projects, not products. They are public so the code can be read and judged directly.
- Compiler backends without LLVM — lexing, parsing, IR design, instruction selection, x86-64 encoding, ABI and calling conventions, binary formats
- Bare-metal systems — UEFI boot chains, GDT/IDT, paging, schedulers, capability-based security, driver development against real hardware
- Debugging where there is no debugger — when a machine boots to a black screen, the only tools are serial output, a specification, and reasoning
Languages: Rust, C, C++, x86-64 assembly, Python, Java
I've also built web work — Angular, TypeScript, React — which paid for the time to do the above.
Independent systems R&D — compilers, operating systems and GPU work, self-directed. Everything above was built alone, and the commit history is public.
Universidad Nacional Federico Villarreal — Computer Engineering, in progress.
Compiler engineering · Systems and OS development · Performance engineering · Remote work
If you want to check whether any of this is real, the fastest way is to download a compiler and run it. That's what it's there for.