Collinear's Internship program is designed for PhD students who are eligible to do a 12-week internship. Start dates are flexible and can be extended. As an MTS - Research Scientist (Applied Scientist), you will help build the data engine for frontier AI. You will develop the high-fidelity environments and evaluation stacks that the world’s leading AI labs rely on to stress-test their most advanced agents. You will work across domains including Computer Use, Enterprise MCP/Toolcalling and Coding. Verifier Design, Simulated Personas, Benchmarking Personal AGI are some of the research areas we work on. Responsibilities: • Build Agentic Environments: Design and implement the next generation of "SimLabs", ultra-realistic, long-horizon simulation environments where agents learn to navigate ambiguity and maintain context. • Programmatic and Agentic Verification: Develop rigorous, policy-aware judges and evaluations that measure genuine capability and safety beyond simple benchmarks. • Close the Loop: Design and execute high-quality post-training runs (CPT, SFT, RL) to deliver frontier performance on open-source models using curated, high-signal data. • Collaborate: Work daily with the founders and research staff to shape the roadmap and push the state-of-the-art in AI reliability. • Create. Work on analyzing model failure modes and creating frontier data pipelines which scale with test-time compute. About You We are looking for individuals who demonstrate a rare combination of technical depth, research intuition, and high agency. • Technical Foundation: A Bachelor’s, Master’s, or PhD in a technical field (CS, Math, Physics, etc.), or a demonstrated "proof of work" through significant open-source contributions or industry experience. • Engineering Rigor: A strong foundation in software engineering with the ability to build robust, scalable infrastructure. You should be comfortable in a Python-friendly, CLI-first development environment. • ML Fluency: A principled understanding of foundation models, including how they are constructed, evaluated, and optimized. • Empirical Mindset: Experience conducting research or technical experiments with a focus on reproducibility and data-driven results. What will make you stand out • Research Taste: You have a strong intuition for identifying what matters in complex problem spaces. You can balance deep research exploration with the pragmatism needed to ship a product. • Impact-Driven Agency: You care about outcomes, not just activity. You don't wait for a ticket; you identify gaps in the system, build the solution, and ensure it moves real-world metrics for frontier AI labs. • Domain Expertise: Prior experience with Reinforcement Learning (RLHF/RLAIF), simulation systems, or building long-horizon agentic environments. • Proven Track Record: A history of contributing to influential ML research (e.g., publications at NeurIPS, ICLR, ICML) or maintaining high-impact open-source projects. • Post-Training Experience: Experience fine-tuning or evaluating large-scale models to deliver "frontier performance" on open-source benchmarks. Why Join Collinear • Own the Frontier: Work on the most pressing problem in AI today: making agents reliable enough for production. • High Density of Talent: Join a small, elite team where you will be pushed to do your life's work. • Elite Compensation: We offer competitive salary and equity packages to ensure we attract the best of the best. • Direct Impact: At a seed-backed startup, your work directly shapes the company's trajectory and the future of AI safety.