Software Engineer, Prompt Encoding & Token Systems

Anthropic Limited; San Francisco (CA); Hybrid; USD 320,000 - 405,000; Full time

Job summary

Anthropic Limited is seeking a Software Engineer for Tokens and Prompt Structures to own design and maintenance of encoding libraries used to encode text and multimodal data for Claude. You will shape how a user turn is represented to the model and how tools are invoked.

This role spans pretraining to finetuning and API work, collaborating closely with researchers and engineers to move encoding ideas from experiment to production, ensuring performance and robustness across the stack.

Qualifications

• 5+ years of software engineering experience, including libs or SDKs.
• Familiarity with ML terminology and LLM architectures.
• Experience refactoring large codebases.
• Strong written and verbal communication with researchers and engineers.
• Results-oriented with flexibility and impact mindset.

Responsibilities

• Maintain and improve encoding libraries for Anthropic's Claude ecosystem.
• Run experiments to optimize data feeding into Claude.
• Design data structures and abstractions to shield org from encoding details while enabling power users.
• Adapt libraries to support new research directions and production deployment.
• Optimize encoding performance across dependent systems.

Skills

5+ years software engineering

ML terminology familiarity

Large codebase refactors

Communication skills

Impact-focused

Education

Bachelor's degree or equivalent

Tools

Python

Rust

Job description

Anthropic Limited is seeking a Software Engineer for Tokens and Prompt Structures to own design and maintenance of encoding libraries used to encode text and multimodal data for Claude. You will shape how a user turn is represented to the model and how tools are invoked.

This role spans pretraining to finetuning and API work, collaborating closely with researchers and engineers to move encoding ideas from experiment to production, ensuring performance and robustness across the stack.