Company: Wasmer ( ) Type: Full-time Location: Remote (CET ± 2) --- Build an operating system that runs everywhere Most engineers spend their careers using operating systems. Its the kind of problem where youre reading Linux kernel source in one tab and the WebAssembly spec in another, deciding how mmap should behave on a platform that was never designed to have one. WASIX itself — designing and implementing syscall semantics, process and threading models, virtual filesystems, and networking stacks on top of WebAssembly.

Where

Linux behavior and Wasm constraints collide, youll be the one deciding what "correct" means. Making real software just work — porting and running battle-tested Unix software (curl, bash, PostgreSQL-class programs) unmodified on WASIX, and fixing everything that breaks along the way. Have 5+ years of systems-level engineering experience, with real-world work on Linux internals, hypervisors (KVM, Xen, Firecracker, etc.), Have proven Rust experience, are fluent C and comfortable diving into large, unfamiliar codebases.

Know POSIX deeply: processes, signals, sockets, file descriptors, memory management — the stuff most people only meet through man pages.

Thrive with high ownership:



you can take a fuzzy problem ("make signals work correctly under Wasm") and drive it from design to shipped code. Versátil and or remote work policies WASIX already runs real software for real developers — which means your design decisions get stress-tested immediately, not in five years. Youll join a small, senior, remote team where the interesting problems arent handed down from an architecture committee — youll find them, scope them, and solve them.

About Wasmer

Wasmer builds the software powering the next generation of computing platforms — local, cloud, and edge — on WebAssembly. Just as Node.js unlocked server-side JavaScript, were unlocking server-side WebAssembly for every language: C/C++, Rust, Go, Python, and beyond. Our mission is to make software universally available. Were an open-source-first company, and we believe the best infrastructure is built in public.

How to apply Send us your CV or LinkedIn — but honestly, we care more about your GitHub, a project youre proud of, or a war story about the gnarliest low-level bug youve ever fixed. Wasmer is a remote-first company.

📌 Senior Engineering Systems Engineer (Antas de Ulla)
🏢 WASMER
📍 Antas de Ulla