Python Jobs

Anthropic

Our Inference team is responsible for building and maintaining the critical systems that serve Claude to millions of users worldwide. We bring Claude to life by serving our models via the industry's largest compute-agnostic inference deployments. We are responsible for the entire stack from intelligent request routing to fleet-wide orchestration across diverse AI accelerators. The team has a dual mandate: maximizing compute efficiency to serve our explosive customer growth, while enabling breakthrough research by giving our scientists the high-performance inference infrastructure they need to develop next-generation models. We tackle complex, distributed systems challenges across multiple accelerator families and emerging AI hardware running in multiple cloud platforms.

Anthropic

Anthropic's research teams are pushing the boundaries of AI safety and capability research, and they need exceptional tools to do their best work. As a Software Engineer on the Research Tools team, you'll build the infrastructure and applications that enable our researchers to iterate quickly, run complex experiments, and extract insights from frontier AI systems. This role sits at the intersection of product thinking and full-stack engineering. You'll work directly with researchers and engineers to deeply understand their workflows, identify bottlenecks, and rapidly ship solutions that multiply their productivity. Whether you're building human feedback interfaces for model evaluation, creating platforms for experiment orchestration, or developing novel visualization tools for understanding model behavior, your work will directly accelerate our mission to build safe, reliable AI systems. We're looking for someone who can operate with high agency in an ambiguous environment—someone who can be dropped into a research team, quickly develop domain expertise, and independently drive impactful projects from conception to delivery.

Anthropic

Anthropic is at the forefront of AI development, making it a prime target for sophisticated actors. The Threat Intelligence function within the Detection & Response team is crucial for anticipating and mitigating these threats. In this role, you will be a hands-on practitioner responsible for generating actionable intelligence that guides our detection, hunting, and defensive strategies. You will track adversaries targeting AI labs, develop tools and pipelines to transform raw indicators into operational defenses, and collaborate closely with detection engineers and incident responders to ensure intelligence effectively influences security outcomes. This is a high-impact, builder-focused role on a small team, offering significant autonomy in shaping how threat intelligence is collected, analyzed, and operationalized at Anthropic.

Anthropic

Anthropic is seeking an exceptional Senior Staff Software Engineer to join the Claude Developer Platform team and serve as the senior-most individual contributor across API Engineering. This role sets the technical direction for the systems that make Claude accessible to developers, enterprises, and partners at scale. You will operate at the intersection of technical strategy and execution, partnering closely with Research, Inference, Platform, Infrastructure, and Safeguards to ensure the Claude API is reliable, capable, and positioned to grow with Anthropic's ambitions. This is a high-agency role that spans all API Engineering teams, including API Core, API Capabilities, API Knowledge, API Distributability, and API Agents.

Anthropic

Anthropic is building reliable, interpretable, and steerable AI systems to be safe and beneficial for users and society. This senior, foundational role on a new team involves making key architectural decisions and shaping initial development. The work is hands-on and varied, encompassing pipeline and infrastructure engineering, prompt tuning, and supporting research teams. The RL Data team focuses on building systems for high-quality reinforcement learning data for Claude, including data collection pipelines, human feedback tooling, execution environments, and quality assurance to ensure trustworthy training data at scale. The goal is to enhance Claude's capabilities in real-world tasks, particularly in AI safety research and beneficial AI deployments.

Anthropic

As part of our growing Data Science and Analytics team, you will play a key role in Anthropic's mission of building safe and beneficial AI by driving data-informed decision-making across the organization. You'll be embedded with teams supporting our Developer Platform — the infrastructure that enables developers and enterprise customers to build on Claude via our core API, agent orchestration, tool and MCP integrations, and knowledge management capabilities. In this role, you'll partner closely with product, engineering, and go-to-market teams to understand how AI agents are being built and deployed at scale. You'll identify growth opportunities, surface insights about platform adoption, and drive data-informed decisions that shape our platform roadmap. You'll also help establish the analytical foundations and best practices of a data science team that is still defining itself — bringing rigor and clarity to a fast-moving environment.

Anthropic

Anthropic is seeking a Research Engineer to join its Pretraining team, focusing on developing the next generation of large language models. This role operates at the intersection of cutting-edge research and practical engineering, aiming to build safe, steerable, and trustworthy AI systems. The mission is to ensure that transformative AI systems are aligned with human interests and are beneficial for society. The team is dedicated to pushing the boundaries of AI while prioritizing safety and ethics.

Anthropic

As an Applied AI team member, you will serve as a Pre-Sales architect, becoming a trusted technical advisor to large enterprises across India and the Asia-Pacific region. Your role will involve helping these organizations understand the value of Claude and envision how to successfully integrate and deploy it into their technology stacks. You will combine deep technical expertise with customer-facing skills to architect innovative LLM solutions that address complex business challenges while upholding high standards for safety and reliability. Working closely with Sales, Product, and Engineering teams, you will guide customers from initial technical discovery through successful deployment, leveraging your expertise to help them understand Claude's capabilities, develop evaluations, and design scalable architectures.

Anthropic

Anthropic is seeking an exceptional Research Scientist to join its Life Sciences team. This role focuses on making Claude a superhuman life sciences research assistant, operating at the intersection of machine learning, software engineering, and biology. You will directly improve model capabilities on scientific tasks through post-training, evaluation design, and RL environment development. As a core member, you will translate deep biological domain knowledge into model training objectives, benchmarks, and agentic workflows, helping establish Anthropic as a leader in AI-accelerated biology and shaping how frontier models reason about computational biology tasks. This is a unique opportunity to shape how frontier AI models learn biology, working alongside top AI researchers on problems crucial for human health and scientific understanding.

Anthropic

The Interpretability team at Anthropic is dedicated to reverse-engineering how trained language models work, believing that a deep mechanistic understanding is crucial for ensuring the safety of advanced AI systems. This role focuses on mechanistic interpretability, aiming to map neural network parameters to meaningful algorithms, akin to performing 'biology' or 'neuroscience' on neural networks. The team's work involves developing tools and methods to understand complex models, addressing challenges like 'superposition' and decomposing models into interpretable components. Collaborations with other Anthropic teams, such as Alignment Science and Societal Impacts, are integral to applying this research to enhance AI safety.

Anthropic

The Frontier Red Team (FRT) is a focused technical research team dedicated to making the world safer in the era of advanced AI. This role involves researching and ensuring safety with self-improving, highly autonomous AI systems, particularly those with cyberphysical capabilities. You will build the tools and frameworks needed to defend against advanced AI-enabled cyber threats, working at the intersection of AI capabilities research, cybersecurity, and policy. This applied research has real-world stakes, informing company decisions, shaping policy discourse, and building technical defenses for the future of AI.

Anthropic

Anthropic is building reliable, interpretable, and steerable AI systems to ensure AI is safe and beneficial for society. As a Research Engineer on the Alignment Science team in London, you will design and execute machine learning experiments to understand and steer the behavior of advanced AI systems. You will focus on AI safety, particularly risks from future human-level AI systems, collaborating with teams like Interpretability and Frontier Red Team. The role involves exploratory research in areas such as AI Control and Alignment Stress-testing, aiming to make AI helpful, honest, and harmless.

Anthropic

Anthropic is seeking a Research Engineer/Scientist for its Alignment Science team. This role involves designing and executing machine learning experiments to understand and steer the behavior of advanced AI systems, with a focus on AI safety and potential risks from future human-level AI. You will collaborate with other teams on exploratory research, contributing to Anthropic's mission of creating reliable, interpretable, and steerable AI systems that are helpful, honest, and harmless.

Anthropic

Safeguards Labs is a new team at Anthropic focused on AI safety, operating at the intersection of research and engineering. The team's mission is to investigate novel safety methods to protect users and the AI system itself. We prototype new approaches to safe models, usage safeguards, and production safety, pressure-testing ideas through offline analysis and subsets of traffic before they are implemented in production systems. This role involves defining and executing the Labs research agenda, scoping projects, running experiments end-to-end, and deciding on the viability of research ideas. The team is structured with a high ratio of researchers to software engineers, offering substantial autonomy and influence over the team's direction.

Anthropic

Anthropic is seeking a Research Engineer to join its Pre-training team, focusing on developing the next generation of large language models. This role operates at the intersection of cutting-edge research and practical engineering, contributing to the creation of safe, steerable, and trustworthy AI systems. The team is dedicated to ensuring that transformative AI systems are aligned with human interests and societal benefit.

Anthropic

Anthropic is seeking passionate Research Scientists and Engineers to join our growing Pre-training team in Zurich. This role is at the intersection of cutting-edge research and practical engineering, contributing to the development of safe, steerable, and trustworthy AI systems. You will be involved in developing the next generation of large language models, with a primary focus on multimodal capabilities, enabling LLMs to understand and interact with modalities beyond text.

Anthropic

Anthropic's production models undergo sophisticated post-training processes to enhance their capabilities, alignment, and safety. As a Research Engineer on our Post-Training team, you'll train our base models through the complete post-training stack to deliver the production Claude models that users interact with. You'll work at the intersection of cutting-edge research and production engineering, implementing, scaling, and improving post-training techniques like Constitutional AI, RLHF, and other alignment methodologies. Your work will directly impact the quality, safety, and capabilities of our production models. Note: For this role, we conduct all interviews in Python. This role may require responding to incidents on short-notice, including on weekends.

Anthropic

Anthropic's production models undergo sophisticated post-training processes to enhance their capabilities, alignment, and safety. As a Research Engineer on our Post-Training team, you'll train our base models through the complete post-training stack to deliver the production Claude models that users interact with. You'll work at the intersection of cutting-edge research and production engineering, implementing, scaling, and improving post-training techniques like Constitutional AI, RLHF, and other alignment methodologies. Your work will directly impact the quality, safety, and capabilities of our production models. For this role, interviews are conducted in Python, and the position may require responding to incidents on short notice, including weekends.

Anthropic

As a Research Engineer within Reinforcement Learning, you will collaborate with a diverse group of researchers and engineers to advance the capabilities and safety of large language models. This role blends research and engineering responsibilities, requiring you to both implement novel approaches and contribute to the research direction. You'll work on fundamental research in reinforcement learning, creating 'agentic' models via tool use for open-ended tasks such as computer use and autonomous software generation, improving reasoning abilities in areas such as mathematics, and developing prototypes for internal use, productivity, and evaluation.

Anthropic

As a Full-Stack Software Engineer in Reinforcement Learning (RL), you will be instrumental in building the platforms, tools, and interfaces essential for environment creation, data collection, and training observability. Your work will directly impact the quality of data used to train Anthropic's next-generation AI models. You will own product surfaces from end-to-end, encompassing backend services, APIs, and web UIs used by researchers, external vendors, and data labelers. The role emphasizes shipping polished, reliable products quickly, even when faced with ambiguous, high-stakes problems. This team operates at a rapid pace, focusing on judgment and taste to meet researcher needs, iterating on data collection strategies to distill expert knowledge into models within short feedback loops.