Software Security Compiler Engineer (m/f/d) - Security Startup

About Variant Security

Variant Security is securing the world's critical fleets for the AI era. Today nearly every device runs identical software, so a single exploit can cascade across an entire fleet of satellites, drones, vehicles, and defense systems, and AI has made finding that one exploit cheaper than ever. Variant breaks that pattern, so compromising one device gives an attacker nothing against the rest and no single failure can bring down the fleet. AI made exploits cheap, and we make them useless, already protecting systems across aerospace, defense, and active conflict zones.

Role Summary

As a Compiler Engineer, you'll build and own the compiler technology at the core of Variant's product, turning cutting-edge diversification into something that ships. You'll work across two areas, the compiler itself and the systems and tooling that run it at fleet scale, with real ownership rather than narrow ticket work. You'll have a direct line to the founding team, immediate impact on what customers run, and room to grow from a strong early-career engineer into the owner of a core domain. Variant Security is securing the world's critical fleets for the AI era. Today nearly every device runs identical software, so a single exploit can cascade across an entire fleet of satellites, drones, vehicles, and defense systems, and AI has made finding that one exploit cheaper than ever. Variant breaks that pattern, so compromising one device gives an attacker nothing against the rest and no single failure can bring down the fleet. AI made exploits cheap, and we make them useless, already protecting systems across aerospace, defense, and active conflict zones.

Tasks

• Develop and extend compiler passes that harden builds against exploitation
• Reverse engineer and analyze the generated binaries to validate transformations
• Measure security and performance impact across x86, AArch64, and RISC-V targets
• Build tooling in modern C++ and Python, and integrate the compiler into CMake and customer CI/CD

Requirements

Must-haves:

• Master's degree, or equivalent hands-on experience, in cybersecurity or computer science
• Hands-on experience with binaries, whether reverse engineering, exploitation, or vulnerability research
• Familiarity with Python and modern C++
• Comfortable reading assembly and debugging low-level code on at least one of x86, AArch64, or RISC-V
• Self-organized and self-driven, with strong personal initiative

Nice-to-haves:

• Prior work on compilers like Clang/LLVM or IR-level transformations
• Familiarity with binary analysis tooling such as Ghidra, IDA, or Binary Ninja
• Knowledge of exploit mitigations (ASLR, CFI, stack canaries, DEP)
• Low-level systems background, spanning embedded, firmware, OS internals, or ELF/PE formats, linkers, and loaders

Benefits

• Work on rare, hard problems where compilers meet binary security, the kind most engineers never get to touch
• Early-stage equity and competitive compensation on the ground floor
• Learn directly from a founding team with deep security, compiler, and space-systems pedigree (top-tier security research, DARPA, SpaceX)
• See your work protect real fleets across aerospace, defense, and active conflict zones
• Based in the Bochum office, with regular collaboration across Germany and the U.S. and the chance to work from or visit the US team

We're looking for builders, hackers, and systems thinkers. If this sounds like you, reach out to us.

Variant Security is the first company to bring an industrialized anti-AI-exploitation technology to market. Rather than racing to patch vulnerabilities faster than AI can discover them, we eliminate the scalability of exploits at the binary level. Our compiler-level technology makes every device in a fleet run its own structurally unique binary, with no code changes and no performance impact. We protect software fleets in aerospace, defense, and critical infrastructure.