C# Jobs

Physical Intelligence is developing foundation models and learning algorithms to power robots and physically-actuated devices. This role is part of the Runtime team, with deep collaboration across Research, Hardware, and Fleet teams. You will drive the architecture and implementation of embedded firmware for critical data collection devices and ensure seamless integration with existing and future data pipelines.

Applied Intuition is seeking a Systems Engineer to join their Robotics team. This role is crucial for defining system requirements, designing architectures, and integrating the company's cutting-edge technology onto autonomous vehicles and defense systems. The position involves a blend of systems engineering, robotics, software deployment, architecture, integration, and real-world testing. You will work in both office and field environments, dedicating significant time to deploying, testing, and validating software on autonomous systems in dynamic, operationally relevant settings. Collaboration with software engineers, autonomy engineers, perception teams, data scientists, and field operators is key to ensuring robust, reliable, and deployment-ready systems.

$60k - $300k

Anthropic

Anthropic is seeking a Performance Engineer for its Inference Engine team. The inference engine is a critical in-house software component that manages the entire token path, from batching requests to coordinating forward passes across accelerator platforms. This role involves building and optimizing this system at scale to enhance throughput, cost-efficiency, reliability, and latency. You will leverage your deep understanding of hardware and bandwidth metrics to model and solve performance bottlenecks. This is a highly technical and impactful position for engineers who thrive on accelerator programming, high-performance host-device coordination, and large-scale distributed systems.

Cloudflare is seeking a Senior Distributed Systems Engineer to join the Cache team. This team builds and operates the high-performance reverse proxy and caching data plane at Cloudflare's edge, built on Pingora, Cloudflare's open-source Rust framework. The role involves working on backend routing, load balancing, cache storage, globally distributed purge, Tiered Cache routing, and production observability. You will design, implement, test, roll out, and operate these systems, ensuring performance, correctness, and resilience across Cloudflare's global network. This position is ideal for individuals who enjoy tackling complex problems related to latency, correctness, and reliability in large-scale distributed systems.

$194k - $266k

This role is designed for new graduates who are eager to work on real-world AI systems in production from day one. As a Member of Technical Staff at Fireworks, you will write and deploy code that operates on one of the world's most active inference platforms, serving hundreds of models to developers and enterprises at a massive scale. You will be matched to a team based on your strengths and interests, with potential work spanning inference and performance, model training and fine-tuning, distributed systems and cloud infrastructure, developer platform and APIs, or product and full-stack application engineering. You will be supported by a senior engineer mentor and a structured ramp-up program, starting with well-scoped problems and progressing to owning features and systems independently. The company emphasizes a fast-paced environment with a high bar and a commitment to employee development.

Crusoe is seeking a Staff Applied AI Inference Engineer to accelerate the abundance of energy and intelligence by optimizing large language models for production environments. This role involves owning the inference stack end-to-end, from profiling costs and implementing modern optimization techniques to deep dives into serving code when defaults are insufficient. The work is applied, focusing on real-world deployments with specific models, traffic patterns, latency targets, and cost constraints. You will collaborate with customer engineering teams to tailor deployments, transition workloads from proof-of-concept to fully monitored production services, and ensure engineered gains benefit end-users. This is a hands-on engineering position requiring coding, profiling, and low-level optimization, with a customer-facing component involving product and technical solutions work.

$215k - $260k

Fireworks is seeking PhD graduates to join their Systems Infrastructure team. This role is designed for individuals finishing their PhD in Computer Science, Computer Engineering, Electrical Engineering, or a similar field, who are interested in applying their research to large-scale, real-world AI infrastructure. You will be responsible for designing and building the core systems that power Fireworks, including schedulers, storage systems, and networks, to ensure efficient operation of tens of thousands of accelerators and low inference latency. You will tackle complex problems such as optimizing job placement on heterogeneous hardware, high-speed data movement for model weights, and maintaining saturated datacenter networks. You will be paired with a senior engineer mentor and work on impactful projects from day one, with start dates flexible around thesis defense.

Fireworks is seeking a Member of Technical Staff on the Research team, designed for PhD candidates who want their work to reach production. This role involves pushing the boundaries of generative AI, advancing LLMs and multimodal systems through foundational research. You will enhance model efficiency, accuracy, and scalability, directly shaping high-performance AI infrastructure. You will be paired with a senior researcher as a mentor and given a real research problem from day one, collaborating with top experts in deep learning, distributed systems, and optimization. The work you contribute will be deployed by leading companies, often within weeks.

Anthropic

Anthropic's Security Governance, Risk, and Compliance (GRC) team is responsible for ensuring the company meets its security and control commitments. This role focuses on the Sarbanes-Oxley (SOX) control environment over the technology stack, crucial for a public company. The position involves defining control requirements and acceptance criteria for IT general controls (ITGCs) in partnership with Internal Audit, and validating that implemented systems meet these requirements. The role also encompasses owning product management for control design methodology and continuous control monitoring, initially for ITGCs and expanding to other security and compliance areas.

SpaceXAI is building a high-performance inference platform that serves Grok to millions of users daily with exceptional speed and reliability. As a Member of Technical Staff - Inference, you will be responsible for designing and optimizing large-scale model serving systems from end-to-end. This includes distributed infrastructure components like global KV cache, continuous batching, and load balancing, as well as deep low-level optimizations such as GPU kernels, quantization, and speculative decoding. This is a high-impact role where your contributions will directly influence the speed and reliability of user interactions with Grok at a massive scale.

$180k - $440k

As a backend engineer, you will design and build scalable, high-performance systems that power subscriptions infrastructure, new monetized products, user growth, and creator monetization. You will work on mission-critical infrastructure that processes millions of transactions, optimizes user acquisition and retention, and enables creators to earn a living through their content. This is a unique opportunity to make a large-scale revenue impact while creating products that users and businesses love.

$150k - $400k

SpaceXAI is seeking exceptional storage & database engineers to join a new project focused on deeply integrating advanced AI infrastructure into a platform used by millions of users monthly. The team is building a new storage tier to power training, inference, recommendations, and real-time data extraction. This involves developing and operating an exabyte-scale S3-compatible object store, a multi-tenant transactional key/value store serving hundreds of millions of requests per second, a caching tier serving billions of requests per second, a scalable vector database for recommendation systems, and other specialized databases.

$180k - $440k

SpaceXAI is seeking a Site Reliability Engineer focused on campus reliability to design and implement systems that ensure the availability and trustworthiness of our campus infrastructure. This role involves technically leading cross-discipline incident responses and building mechanisms to minimize future incidents. You will act as the central point of contact across compute, network, storage, power, and cooling systems, requiring strong incident leadership, fleet-scale observability expertise, and the ability to drive reliability improvements across both software and facility domains.

The Sandbox service team at SpaceXAI builds and maintains a secure, scalable system that gives our models safe, controlled access to computational environments. This infrastructure powers critical workloads across training and product, enabling models to run code, build software, interact with tools, and even control applications with user interfaces. We provision containers and virtual machines on large-scale clusters, granting models interactive control over these remote environments. Our work spans the full stack: from orchestrating massive jobs and resource scheduling at the cluster level, to fine-tuning filesystem performance on nodes. The Sandbox service enables Grok to safely run and test code in real-time for user queries, and supports reinforcement learning in training, where models interactively explore tools ranging from compilers to productivity apps.

£107k - £262k

SpaceXAI is seeking an engineer to join the RL infrastructure team to help develop our RL training framework. The team is small, highly motivated, and focused on engineering excellence, operating with a flat organizational structure where all employees are expected to be hands-on and contribute directly to the company's mission. This role requires strong initiative, curiosity, work ethic, prioritization, and communication skills.

$180k - $440k

SpaceXAI's mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. The RL infrastructure team is looking for an engineer to help with low precision RL training and inference. This role involves designing and optimizing the inference stack for all shapes of RL workloads, analyzing and addressing performance bottlenecks in large-scale RL systems, and working closely with the modeling team to efficiently implement novel RL techniques and algorithms.

$180k - $440k

SpaceXAI is seeking a Member of Technical Staff to join their multimodal team and advance the understanding and generation of AI across image, video, audio, and text. This role involves working across the full stack, from data curation and pre-training to alignment, infrastructure, and end-to-end product experiences. You will collaborate with various teams to deliver cutting-edge multimodal reasoning, world modeling, tool use, agentic behaviors, and human-AI collaboration capabilities. The goal is to build models that can perceive, reason about, and interact with the world in real-time at an unprecedented level.

$180k - $440k

SpaceXAI is seeking a multimodal engineer for the Imagine Model Team to develop cutting-edge AI experiences beyond text, focusing on high-fidelity understanding and generation across image and video modalities, with audio integration where it enhances visual content. Responsibilities cover data curation, modeling, training, inference serving, and product integration across pretraining and post-training phases. The role involves close collaboration with product teams to advance model frontiers and deliver exceptional end-to-end user experiences.

$180k - $440k

The Enterprise Agents Engineering Team at SpaceXAI focuses on solving complex problems in applied AI, specifically integrating with diverse systems, orchestrating intricate workflows, and leveraging AI to revolutionize business operations. This role involves building full-stack solutions with end-to-end product ownership, from initial concept to deployment. You will collaborate closely with the team to integrate advanced AI technologies into dependable, user-focused solutions, employing an iterative development process. Working hand-in-hand with customers, you will gather feedback, refine features, and evolve products to meet real-world demands.

SpaceXAI is building AI systems to understand the universe and aid humanity. The team is small, highly motivated, and focused on engineering excellence, operating with a flat structure where all employees are hands-on and contribute directly to the mission. This role requires strong communication skills and the ability to share knowledge concisely. The ideal candidate will have a good understanding of building highly scalable and reliable production infrastructure, with familiarity in compiled languages like Rust, C++, or Go being highly beneficial.

£107k - £262k