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  <jobs>
    <job>
      <externalid>faffcca4-e94</externalid>
      <Title>Research Engineer, Cybersecurity Reinforcement Learning</Title>
      <Description><![CDATA[<p>About the role</p>
<p>We&#39;re hiring for the Cybersecurity RL team within Horizons. As a Research Engineer, you&#39;ll help to safely advance the capabilities of our models in secure coding, vulnerability remediation, and other areas of defensive cybersecurity.</p>
<p>This role blends research and engineering, requiring you to both develop novel approaches and realize them in code. Your work will include designing and implementing RL environments, conducting experiments and evaluations, delivering your work into production training runs, and collaborating with other researchers, engineers, and cybersecurity specialists across and outside Anthropic.</p>
<p>The role requires domain expertise in cybersecurity paired with interest or experience in training safe AI models. For example, you might be a white hat hacker who&#39;s curious about how LLMs could augment or transform your work, a security engineer interested in how AI could help harden systems at scale, or a detection and response professional wondering how models could enhance defensive workflows.</p>
<p>Responsibilities</p>
<ul>
<li>Design and implement RL environments for secure coding and vulnerability remediation</li>
<li>Conduct experiments and evaluations to assess the effectiveness of our models</li>
<li>Deliver your work into production training runs to advance the capabilities of our models</li>
<li>Collaborate with other researchers, engineers, and cybersecurity specialists across and outside Anthropic</li>
</ul>
<p>Requirements</p>
<ul>
<li>Experience in cybersecurity research</li>
<li>Experience with machine learning</li>
<li>Strong software engineering skills</li>
<li>Ability to balance research exploration with engineering implementation</li>
<li>Passion for AI&#39;s potential and commitment to developing safe and beneficial systems</li>
</ul>
<p>Strong candidates may also have:</p>
<ul>
<li>Professional experience in security engineering, fuzzing, detection and response, or other applied defensive work</li>
<li>Experience participating in or building CTF competitions and cyber ranges</li>
<li>Academic research experience in cybersecurity</li>
<li>Familiarity with RL techniques and environments</li>
<li>Familiarity with LLM training methodologies</li>
</ul>
<p>Logistics</p>
<ul>
<li>Minimum education: Bachelor’s degree or an equivalent combination of education, training, and/or experience</li>
<li>Required field of study: A field relevant to the role as demonstrated through coursework, training, or professional experience</li>
<li>Minimum years of experience: Years of experience required will correlate with the internal job level requirements for the position</li>
<li>Location-based hybrid policy: Currently, we expect all staff to be in one of our offices at least 25% of the time. However, some roles may require more time in our offices.</li>
<li>Visa sponsorship: We do sponsor visas! However, we aren&#39;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.</li>
</ul>
<p>We encourage you to apply even if you do not believe you meet every single qualification. Not all strong candidates will meet every single qualification as listed. Research shows that people who identify as being from underrepresented groups are more prone to experiencing imposter syndrome and doubting the strength of their candidacy, so we urge you not to exclude yourself prematurely and to submit an application if you&#39;re interested in this work.</p>
<p>Your safety matters to us. To protect yourself from potential scams, remember that Anthropic recruiters only contact you from @anthropic.com email addresses. In some cases, we may partner with vetted recruiting agencies who will identify themselves as working on behalf of Anthropic. Be cautious of emails from other domains. Legitimate Anthropic recruiters will never ask for money, fees, or banking information before your first day. If you&#39;re ever unsure about a communication, don&#39;t click any links,visit anthropic.com/careers directly for confirmed position openings.</p>
<p>How we&#39;re different</p>
<p>We believe that the highest-impact AI research will be big science. At Anthropic we work as a single cohesive team on just a few large-scale research efforts. And we value impact , advancing our long-term goals of steerable, trustworthy AI , rather than work on smaller and more specific puzzles. We view AI research as an empirical science, which has as much in common with physics and biology as with traditional efforts in computer science. We&#39;re an extremely collaborative group, and we host frequent research discussions to ensure that we are pursuing the highest-impact work at any given time. As such, we greatly value communication skills.</p>
<p>The easiest way to understand our research directions is to read our recent research. This research continues many of the directions our team worked on prior to Anthropic, including: GPT-3, Circuit-Based Interpretability, Multimodal Neurons, Scaling Laws, AI &amp; Compute, Concrete Problems in AI Safety, and Learning from Human Preferences.</p>
<p>Come work with us!</p>
<p>Anthropic is a public benefit corporation headquartered in San Francisco. We offer competitive compensation and benefits, optional equity donation matching, generous vacation and parental leave, flexible working hours, and a lovely office space in which to collaborate with colleagues.</p>
<p style="margin-top:24px;font-size:13px;color:#666;">XML job scraping automation by <a href="https://yubhub.co">YubHub</a></p>]]></Description>
      <Jobtype>full-time</Jobtype>
      <Experiencelevel>mid</Experiencelevel>
      <Workarrangement>hybrid</Workarrangement>
      <Salaryrange>$300,000-$405,000 USD</Salaryrange>
      <Skills>cybersecurity research, machine learning, software engineering, research exploration, engineering implementation, security engineering, fuzzing, detection and response, RL techniques, LLM training methodologies</Skills>
      <Category>Engineering</Category>
      <Industry>Technology</Industry>
      <Employername>Anthropic</Employername>
      <Employerlogo>https://logos.yubhub.co/anthropic.com.png</Employerlogo>
      <Employerdescription>Anthropic is a public benefit corporation that creates reliable, interpretable, and steerable AI systems.</Employerdescription>
      <Employerwebsite>https://www.anthropic.com/</Employerwebsite>
      <Compensationcurrency></Compensationcurrency>
      <Compensationmin></Compensationmin>
      <Compensationmax></Compensationmax>
      <Applyto>https://job-boards.greenhouse.io/anthropic/jobs/5025624008</Applyto>
      <Location>San Francisco, CA | New York City, NY</Location>
      <Country></Country>
      <Postedate>2026-04-18</Postedate>
    </job>
    <job>
      <externalid>540ce49c-271</externalid>
      <Title>Member of Technical Staff - Multimodal Understanding</Title>
      <Description><![CDATA[<p><strong>About the Role</strong></p>
<p>You will join the multimodal team to push toward superhuman multimodal intelligence. Advance understanding and generation across modalities,image, video, audio, and text,spanning the full stack: data curation/acquisition, tokenizer training, large-scale pre-training, post-training/alignment, infrastructure/scaling, evaluation, tooling/demos, and end-to-end product experiences.</p>
<p>Collaborate cross-functionally with pre-training, post-training, reasoning, data, applied, and product teams to deliver frontier capabilities in multimodal reasoning, world modeling, tool use, agentic behaviors, and interactive human-AI collaboration. Contribute to building models that can see, hear, reason about, and interact with the world in real time at unprecedented levels.</p>
<p><strong>Responsibilities</strong></p>
<ul>
<li>Design, build, and optimize large-scale distributed systems for multimodal pre-training, post-training, inference, data processing, and tokenization at web/petabyte scale.</li>
<li>Develop high-throughput pipelines for data acquisition, preprocessing, filtering, generation, decoding, loading, crawling, visualization, and management (images, videos, audio + text).</li>
<li>Advance multimodal capabilities including spatial-temporal compression, cross-modal alignment, world modeling, reasoning, emergent abilities, audio/image/video understanding &amp; generation, real-time video processing, and noisy data handling.</li>
<li>Drive data quality and studies: curation (human/synthetic), filtering techniques, analysis, and scalable pipelines to support trillion-parameter models.</li>
<li>Create evaluation frameworks, internal benchmarks, reward models, and metrics that capture real-world usage, failure modes, interactive dynamics, and human-AI synergy.</li>
<li>Innovate on algorithms, modeling approaches, hardware/software/algorithm co-design, and scaling paradigms for state-of-the-art performance.</li>
<li>Build research tooling, user-friendly interfaces, prototypes/demos, full-stack applications, and enable rapid iteration based on feedback.</li>
<li>Work across the stack (pre-training → SFT/RL/post-training) to enable reasoning, tool calling, agentic behaviors, orchestration, and seamless real-time interactions.</li>
</ul>
<p><strong>Basic Qualifications</strong></p>
<ul>
<li>Hands-on experience with multimodal pre-training, post-training, or fine-tuning (vision, audio, video, or cross-modal).</li>
<li>Expert-level proficiency in Python (core language), with strong experience in at least one of: JAX / PyTorch / XLA.</li>
<li>Proven track record building or optimizing large-scale distributed ML systems (training/inference optimization, GPU utilization, multi-GPU/TPU setups, hardware co-design).</li>
<li>Deep experience designing and running data pipelines at scale: curation, filtering, generation, quality studies, especially for noisy/real-world multimodal data.</li>
<li>Strong fundamentals in evaluation design, benchmarks, reward modeling, or RL techniques (particularly for interactive/agentic behaviors).</li>
<li>Proactive self-starter who thrives in high-intensity environments and is passionate about pushing multimodal AI frontiers.</li>
<li>Willingness to own end-to-end initiatives and do whatever it takes to deliver breakthrough user experiences.</li>
</ul>
<p><strong>Preferred Skills and Experience</strong></p>
<ul>
<li>Experience leading major improvements in model capabilities through better data, modeling, algorithms, or scaling.</li>
<li>Familiarity with state-of-the-art in multimodal LLMs, scaling laws, tokenizers, compression techniques, reasoning, or agentic systems.</li>
<li>Proficiency in Rust and/or C++ for performance-critical components.</li>
<li>Hands-on work with large-scale orchestration tools such as Spark, Ray, or Kubernetes.</li>
<li>Background building full-stack tooling: performant interfaces, real-time research demos/apps, or end-to-end product ownership.</li>
<li>Passion for end-to-end user experience in interactive, real-time multimodal AI systems.</li>
</ul>
<p style="margin-top:24px;font-size:13px;color:#666;">XML job scraping automation by <a href="https://yubhub.co">YubHub</a></p>]]></Description>
      <Jobtype>full-time</Jobtype>
      <Experiencelevel>staff</Experiencelevel>
      <Workarrangement>onsite</Workarrangement>
      <Salaryrange>$180,000 - $440,000 USD</Salaryrange>
      <Skills>Multimodal pre-training, Post-training, Fine-tuning, Python, JAX, PyTorch, XLA, Large-scale distributed ML systems, Data pipelines, Evaluation design, Benchmarks, Reward modeling, RL techniques, State-of-the-art in multimodal LLMs, Scaling laws, Tokenizers, Compression techniques, Reasoning, Agentic systems, Rust, C++, Spark, Ray, Kubernetes, Full-stack tooling</Skills>
      <Category>Engineering</Category>
      <Industry>Technology</Industry>
      <Employername>xAI</Employername>
      <Employerlogo>https://logos.yubhub.co/xai.com.png</Employerlogo>
      <Employerdescription>xAI creates AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge.</Employerdescription>
      <Employerwebsite>https://www.xai.com</Employerwebsite>
      <Compensationcurrency></Compensationcurrency>
      <Compensationmin></Compensationmin>
      <Compensationmax></Compensationmax>
      <Applyto>https://job-boards.greenhouse.io/xai/jobs/5111374007</Applyto>
      <Location>Palo Alto, CA</Location>
      <Country></Country>
      <Postedate>2026-04-18</Postedate>
    </job>
  </jobs>
</source>