Anthropic · 18 hours ago
Software Engineer, Encoding Libraries
San Francisco, CA
Full-time
Hybrid
Senior Level
$300K/yr - $405K/yr
5+ years expAnthropic is a public benefit corporation focused on creating reliable and interpretable AI systems. They are seeking a Software Engineer for their Encodings Infrastructure team to maintain and improve libraries used for encoding text and multimodal data, ensuring intuitive APIs and high performance while collaborating closely with researchers and engineers.
Artificial Intelligence (AI)Foundational AIGenerative AIInformation TechnologyMachine Learning
Responsibilities
Maintain and improve the encoding libraries used by engineers and researchers across Anthropic, with a focus on clean, user-friendly APIs
Design data structures and abstractions that shield most of the organization from the details of how encoded data works while enabling “power users”
Adapt the encoding libraries to support new research directions as they emerge, and make sure that we can ship these research ideas to production
Optimize encoding performance across the systems that depend on these libraries
Work across Anthropic's codebase to improve how encoded and unencoded data is handled
Qualification
Required
5+ years of software engineering experience, with meaningful time spent maintaining libraries, SDKs, or developer-facing APIs
Familiarity with ML terminology and LLM architecture — you don't need to be an ML expert, but enough understanding to work effectively alongside researchers
Experience carrying out complex refactors in large codebases
Strong communication skills and enjoy working closely with researchers and engineers to understand what they need
Results-oriented, with a bias towards flexibility and impact
Pick up slack, even if it goes outside your job description
Care about the societal impacts of your work
At least a Bachelor's degree in a related field or equivalent experience
Preferred
Tokenizers or other text/data encoding systems
Maintaining a widely-used library over a long period of time
Performance optimization
Python and/or Rust
Reinforcement learning or model training infrastructure
Benefits
Optional equity donation matching
Generous vacation and parental leave
Flexible working hours
Company
Anthropic
Anthropic is an AI research company that focuses on the safety and alignment of AI systems with human values.
501-1000 employees
H1B Sponsorship
Anthropic has a track record of offering H1B sponsorships. Please note that this does not
guarantee sponsorship for this specific role. Below presents additional info for your
reference. (Data Powered by US Department of Labor)
Distribution of Different Job Fields Receiving Sponsorship
Represents job field similar to this job
Trends of Total Sponsorships
2025 (105)
2024 (13)
2023 (3)
2022 (4)
2021 (1)
Funding
Current Stage
Late StageTotal Funding
$33.74BKey Investors
Fidelity,ICONIQ Capital,Lightspeed Venture PartnersLightspeed Venture PartnersGoogle
2025-09-02Series F· $13B
2025-05-16Debt Financing· $2.5B
2025-03-03Series E· $3.5B
Leadership Team
Dario Amodei
Co-Founder and CEO
Daniela Amodei
President and co-founder
Recent News
2026-02-06
2026-02-06
2026-02-06
Company data provided by crunchbase