Research Engineer - Machine Learning, RL Velocity
About the job
- Strong software engineering fundamentals and a track record of building performant, reliable systems.
- Experience with machine learning infrastructure, distributed systems, or research tooling.
- Comfort operating across the stack, from low-level performance work to reinforcement learning algorithms.
- Build and improve the reinforcement learning training infrastructure that researchers depend on day-to-day.
- Identify and remove bottlenecks across the reinforcement learning stack by debugging, profiling, and rearchitecting where needed.
- Partner with researchers and adjacent engineering teams, including inference and sandboxing, to understand pain points and ship tooling that makes them faster.
- Own the reliability and performance of research runs end-to-end.
- Contribute to design decisions that shape how Anthropic does reinforcement learning at scale.
- Experience with large-scale distributed training, including reinforcement learning, pre-training, or post-training.
- Familiarity with JAX, PyTorch, or similar machine learning frameworks.
- A track record of operating at the edge of research and infrastructure in a fast-moving environment.
About the company
Anthropic builds the Claude family of AI models and sells them to businesses, software developers, and consumers, with research on making AI safe and understandable at the center of its work. In 2024 it introduced the Model Context Protocol, an open standard for connecting AI assistants to outside apps and data that OpenAI and Google adopted the next year. People use the Claude app to write and analyze files, programmers hand coding tasks to Claude Code, and companies build Claude into their own products through its API. Anthropic earns money from subscriptions, business plans, and usage-based API fees. Siblings Dario and Daniela Amodei founded Anthropic in 2021 with other former OpenAI employees, and it is based in San Francisco.
Company Size
5,001-10,000
Company Stage
N/A
Total Funding
$224.8B
Headquarters
San Francisco, California
Founded
2021
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Simplify's Take
What believers are saying
- Sales are multiplying: Anthropic's yearly revenue pace topped $65 billion in July 2026, over sevenfold since December 2025.
- IPO plans advanced: October 2026 reports describe investor meetings and a mid-November listing target; staff shares face lockups.
- Lower office minimum: 627 of 646 Anthropic job posts in October 2026 require at least 25% office time.
What critics are saying
- Job security rides on growth: Anthropic's IPO prospectus lists $518 billion in cloud and computing bills due in coming years.
- Defense work stays off-limits: in September 2026, appeals judges voted 2-1 to let the Pentagon keep blacklisting Anthropic.
- Growth is priced in: Anthropic's valuation reached $965 billion in May 2026, up from $380 billion in February.
What makes Anthropic unique
- Investors don't control its board alone: Anthropic's independent Long-Term Benefit Trust elects a growing number of directors.
- It isn't tied to one chipmaker: Claude runs on Nvidia GPUs plus custom AI chips designed by Google and Amazon.
- It holds back its riskiest model: Claude Mythos 5.1, launched September 2026, goes only to vetted cyberdefenders and life scientists.
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Benefits
Flexible Work Hours
Paid Vacation
Parental Leave
Hybrid Work Options
Company Equity
Growth & Insights and Company News
6 month growth
↑ 0%1 year growth
↑ 3%2 year growth
↓ -3%OpenAI and Anthropic are hiring former Trump administration officials for senior roles as AI companies strengthen ties with Washington. Anthropic has appointed at least two ex-Trump officials this year, including Chris Liddell to its board and Sihao Huang as head of frontier compute strategy. OpenAI has hired at least three, including Thomas Lind for cyber and strategic risk, and Dean Ball as head of strategic futures. The moves come as frontier AI is increasingly viewed as a national security issue, with companies seeking to build relationships amid growing regulatory calls. Trump has called AI safety concerns a "hoax" whilst also suggesting law enforcement could "rein in" AI. Both companies are currently hiring for multiple political engagement roles as they prepare for potential public listings.
Chip and cloud stocks edged higher in overnight trading after OpenAI's revenue disclosure sparked a sharp selloff on Thursday. Nvidia rose 0.5%, whilst Oracle and CoreWeave gained 0.7% and 0.3% respectively. The iShares semiconductor ETF added 0.03% after sliding 3.4% in the regular session. OpenAI reported roughly $50 billion in annualised revenue at the end of September, lower than the previously reported $70 billion figure. Analysts said the discrepancy stemmed from different accounting methods when comparing OpenAI's revenue with competitor Anthropic's. The Futurum Group CEO Daniel Newman called the broader market reaction "overblown", noting OpenAI could still reach $70 billion to $90 billion in revenue by year-end. In a Stocktwits poll, 48% of retail investors said they plan to buy AI-linked stocks following the dip.
American tech companies are expanding data centre operations in Australia, but face growing opposition from residents and farmers. Local communities near Melbourne are protesting planned facilities, citing concerns over noise, energy consumption, and water usage. Investment in Australian data centres could exceed $100 billion by 2030, according to the Commonwealth Bank of Australia, with Microsoft and Amazon already committing funding. Companies are attracted by Australia's geographic location, renewable energy access, and democratic stability. However, the expansion faces obstacles. New regulations on water efficiency and power supply take effect next year. Australia's strict copyright protections pose challenges for AI companies seeking regulatory certainty. Recent revelations that an OpenAI agent accessed Australian government websites without authorisation have intensified scrutiny. Experts question whether AI companies should receive special treatment regarding accountability.
Anthropic has launched its Cyber Mission programme to help patch software vulnerabilities exposed by its own AI tools. The company acknowledges that attackers currently have the advantage, but predicts defenders will gain the upper hand within two years. The initiative focuses on two areas: a Critical Infrastructure Defense Program, partnering with firms like CrowdStrike and Palo Alto Networks to protect utilities from AI-discovered vulnerabilities, and OSS Scanner, offering free security scans to established open-source projects. According to Anthropic, AI models now find over 85% of vulnerabilities, up from 20% at the start of 2025. The programme follows recent incidents where AI agents broke into at least 20 organisations, including HuggingFace, raising concerns about AI-enabled cyberattacks.
Anthropic has launched a cyber programme targeting critical infrastructure and introduced OSS Scanner, a free opt-in service for open-source projects that handles vulnerability reports. The AI-generated reports come without human review and may contain inaccuracies. Earlier this week, Anthropic integrated Project Glasswing into its Cyber Verification Program, expanding model access for eligible defenders. Google noted that automated security findings can create additional triage work for maintainers. The Open Source Security Foundation warned that AI-generated disclosures risk adding low-quality noise. The launch reflects a broader trend of vendors marketing AI-enabled cyber defence tools to critical infrastructure operators.