Join Assert Labs

We are a team of engineers and researchers with an ambitious mission: to move the world toward error-free software. We're doing this by building tools to autonomously test and analyze code. We are backed by Accel, Guillermo Rauch (Vercel), Thomas Wolf (Hugging Face), David Cramer (Sentry), Charlie Marsh (Astral), and a number of other open source developers, machine learning researchers, and entrepreneurs. If you wish to learn more, read here about our mission and values.

Our Culture

• -We are assembling a lean group of generalists. While we welcome experience, we're primarily looking for creative, curious problem solvers with a keen interest in open-ended, technically challenging problems.
• -We want to work with people who care deeply about the mission of the company and enjoy the work required to achieve it.
• -We work in person in our office in San Francisco. We believe that having a community is critical for learning, growth, and camaraderie. We pay generously for relocation assistance.
• -We invest heavily in our team's growth. We sponsor conference attendance (NeurIPS, ICML, RustConf, PyCon, etc.), run an internal paper reading group, and encourage blogging/publishing research. If there's something that will help you grow as an engineer or researcher, we actively want to support it.
• -We believe in compensating exceptional talent exceptionally well. We benchmark our compensation against the top 90th percentile for each role, and we're committed to working with candidates we're excited about to ensure they are excited too.
• -We have an academic as well as competitive spirit. We enjoy thought exercises, math puzzles, intellectual inquiry, and vigorous debates. Outside of working hours we enjoy playing board games like Chess, Go, and Diplomacy.

Role: Language & Runtime Engineer

Understand, instrument, and model live program behavior. We're building novel tools to analyze and understand how programs execute across different languages and runtimes. This involves developing sophisticated instrumentation techniques, creating high-performance profiling infrastructure, and designing abstractions that work across multiple programming languages. This role combines deep systems knowledge with programming language expertise to advance the state of the art in runtime analysis.

Responsibilities

• -Design and implement novel instrumentation techniques for analyzing program behavior across multiple languages and runtimes
• -Build high-performance profiling and tracing infrastructure to capture detailed runtime characteristics with minimal overhead
• -Develop language-agnostic abstractions for representing and analyzing program execution patterns
• -Create tools for runtime verification, debugging, and performance optimization that work across different programming languages
• -Contribute to the development of language specifications and runtime implementations

Qualifications

• -Deep expertise in programming language implementation, including experience with compilers, interpreters, or runtime systems
• -Strong background in program analysis techniques, both static and dynamic
• -Proficiency in systems programming languages (Rust, C/C++) and experience with language runtime internals
• -Experience with performance profiling, debugging tools, or runtime instrumentation frameworks
• -Familiarity with formal methods, type systems, or program verification techniques
• -Background in garbage collection, JIT compilation, or virtual machine implementation

Interview Process

Our interview process is designed to be unusually thorough yet efficient, respecting our time as well as yours. We occasionally accelerate the process or skip steps for candidates.