Weekly digest
Week of 29 December 2025
9 new roles this week across 6 companies; the biggest movers: RadixArk (+3), World Labs (+2).
Research
- Research Scientist (Generative Modeling) — World Labs Builds 3D world generation models that create spatially consistent environments from text, images, and video
ML engineering
- Member of Technical Staff — Inference-TPU — RadixArk Builds open-source inference and training infrastructure systems for AI applications
Infrastructure
- Member of Technical Staff — Backend/API Platform — RadixArk
- Staff Software Engineer, Developer Infrastructure — Sesame AI Sesame Technology is a multifaceted technology company with diverse offerings
- Structural Engineer - Data Centers — xAI Develops Grok, an AI platform offering reasoning, code, voice, image, and video capabilities through a unified
- AI Infra Resident (1-Year Program) — RadixArk
Software
- Senior/Principal Physical Design Engineer — Fractile Builds specialized processors that fuse computation with memory to run large language models up to 25x faster
- Senior Product Engineer (Tech Lead) — World Labs
Operations
- Supply Chain Planner — K2 Space Builds high-power satellite buses designed for LEO, MEO, and GEO missions with 10x more power than constellati
Every line links to the role on Liftoff Jobs, and from there to the company's own board. · Past issues · Search the whole index
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