Member of Technical Staff - Applied AI

Tzafon is a foundation model lab building scalable compute systems and advancing machine intelligence, with offices in San Francisco, Zurich & Tel Aviv. We've raised over $12m in funding to advance our mission of expanding the frontiers of machine intelligence.We're a team of engineers and scientists with deep backgrounds in ML infrastructure & research. Founded by IOI and IMO medalists, PhDs, and alumni from leading tech companies, we train models and build infrastructure for swarms of agents to automate work across real-world environments.You'll work between our product and post-training teams to ship Large Action Models that actually work. Build evals, benchmarks, and fine-tuning pipelines. Define what good model behavior means and make it happen at scale.What you'll doBuild evaluation infrastructure for agent systemsCreate benchmarks that measure real capabilityDesign data pipelines for behavioral data collection and analysisImplement fine-tuning pipelines (wandb, distributed training infrastructure)Work with post-training team on RLHF and behavioral optimizationBuild tools for model introspection and capability mappingShip continuous evaluation systems that catch regressions before users doWe're looking forExpert-level at Python and ML frameworks (PyTorch)Deep experience with LLM fine-tuning and evaluation infrastructureTrack record of shipping ML systems to productionStrong opinions on what makes a good evalExperience with wandb, MLflow, or similar experiment trackingPreferred ExperienceBuilt eval frameworks at AI labs or LLM companiesRLHF/Constitutional AI/DPO implementation experiencePublished work on model evaluation or benchmarkingContributions to open source ML infrastructureExperience with multi-agent systems or tool-use modelsLife at TzafonFull medical, dental, and vision coverage, plus 401(k)Office in SF and Tel AvivEarly-stage equity in a future-defining companyVisa sponsorship: We do sponsor visas! However, we aren't able to successfully sponsor visas for every role and every candidate. But if we make you an offer, we will make every reasonable effort to get you a visa, and we retain an immigration lawyer to help with this.Compensation starts at $150k-$400k + equity package, depending on experience & location.We also offer a referral bonus of $5k for referral of successful hires (send to ).

Created: 2026-04-02