Full-Time

Machine Learning Systems Engineer

Encodings and Tokenization

Posted on 7/2/2025

Anthropic

Anthropic

5,001-10,000 employees

Develops reliable, interpretable AI systems

Compensation Overview

$320k - $405k/yr

+ Equity + Benefits + Incentive Compensation

H1B Sponsorship Available

San Francisco, CA, USA

In Person

Currently, we expect all staff to be in one of our offices at least 25% of the time.

Category
AI & Machine Learning (1)
Required Skills
Python
Machine Learning
Data Analysis
Requirements
  • Have significant software engineering experience with demonstrated machine learning expertise
  • Are comfortable navigating ambiguity and developing solutions in rapidly evolving research environments
  • Can work independently while maintaining strong collaboration with cross-functional teams
  • Are results-oriented, with a bias towards flexibility and impact
  • Have experience with machine learning systems, data pipelines, or ML infrastructure
  • Are proficient in Python and familiar with modern ML development practices
  • Have strong analytical skills and can evaluate the impact of engineering changes on research outcomes
  • Pick up slack, even if it goes outside your job description
  • Enjoy pair programming (we love to pair!)
  • Care about the societal impacts of your work and are committed to developing AI responsibly
Responsibilities
  • Design, develop, and maintain tokenization systems used across Pretraining and Finetuning workflows
  • Optimize encoding techniques to improve model training efficiency and performance
  • Collaborate closely with research teams to understand their evolving needs around data representation
  • Build infrastructure that enables researchers to experiment with novel tokenization approaches
  • Implement systems for monitoring and debugging tokenization-related issues in the model training pipeline
  • Create robust testing frameworks to validate tokenization systems across diverse languages and data types
  • Identify and address bottlenecks in data processing pipelines related to tokenization
  • Document systems thoroughly and communicate technical decisions clearly to stakeholders across teams
Desired Qualifications
  • Working with machine learning data processing pipelines
  • Building or optimizing data encodings for ML applications
  • Implementing or working with BPE, WordPiece, or other tokenization algorithms
  • Performance optimization of ML data processing systems
  • Multi-language tokenization challenges and solutions
  • Research environments where engineering directly enables scientific progress
  • Distributed systems and parallel computing for ML workflows
  • Large language models or other transformer-based architectures (not required)

Anthropic focuses on AI research to build reliable, interpretable, and steerable AI systems. Its main product, Claude, is an AI assistant designed to handle tasks at any scale for clients across industries, delivered through deployment and licensing along with specialized AI R&D services. Claude works by combining natural language processing, human feedback, reinforcement learning, and interpretability techniques to produce a capable, controllable AI assistant that can assist with a wide range of tasks. The company differentiates itself from competitors by prioritizing safety, transparency, and controllability—emphasizing reliability, interpretability of model behavior, and user-controlled steerability in its AI systems. Anthropic’s goal is to make AI systems that people can trust and efficiently use to improve operations and decision-making across sectors.

Company Size

5,001-10,000

Company Stage

Late Stage VC

Total Funding

$77.3B

Headquarters

San Francisco, California

Founded

2021

Simplify Jobs

Simplify's Take

What believers are saying

  • Anthropic signed $1.8B seven-year cloud deal with Akamai in 2026.
  • Anthropic accesses 220,000 Nvidia GPUs via SpaceX Colossus lease.
  • Anthropic fields $1tn valuation offers amid $40B annualized revenue.

What critics are saying

  • Litigation erupts in 3-6 months from voiding Forge and Hiive trades.
  • SpaceX reclaims GPUs in 12-24 months if Claude harms humanity.
  • South Korea and Singapore regulators ban Claude in 6-12 months.

What makes Anthropic unique

  • Anthropic pioneered constitutional AI to train Claude models on ethical principles.
  • Anthropic operates as public benefit corporation prioritizing AI safety and reliability.
  • Anthropic founded in 2021 by ex-OpenAI leaders Dario and Daniela Amodei.

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Benefits

Flexible Work Hours

Paid Vacation

Parental Leave

Hybrid Work Options

Company Equity

Growth & Insights and Company News

Headcount

6 month growth

-3%

1 year growth

-3%

2 year growth

1%
Ars Technica
Apr 21st, 2026
Mozilla: Anthropic's Mythos AI model finds 271 zero-day bugs in Firefox 150

Mozilla has discovered 271 security vulnerabilities in Firefox 150 using early access to Anthropic's Mythos Preview AI model. The findings represent a significant increase from the 22 bugs detected by Anthropic's Opus 4.6 model in Firefox 148 last month. Firefox CTO Bobby Holley said Mythos is "every bit as capable" as the world's best security researchers, whilst eliminating the need to "concentrate many months of costly human effort to find a single bug". He believes AI tools like Mythos tilt the cybersecurity balance towards defenders by making vulnerability discovery cheaper. Anthropic released Mythos Preview to a limited group of industry partners earlier this month. Mozilla CTO Raffi Krikorian argues such tools are particularly crucial for open source projects, which often rely on insufficient volunteer maintenance for security.

Bloomberg L.P.
Apr 21st, 2026
Anthropic's Mythos AI sparks fear and hope over cybersecurity threats to global finance

Anthropic's new AI model Mythos has sparked concern amongst policymakers at International Monetary Fund meetings over its potential to accelerate sophisticated cyberattacks on the global financial system. However, its developers argue the technology could provide banks with their strongest defence yet. What distinguishes Mythos is its ability to chain multiple security weaknesses into coordinated attacks, effectively automating complex cyber intrusions. This capability could significantly expand the pool of potential attackers in the near term. The model's creators emphasise a longer-term benefit: the same technology could enable banks to detect and patch vulnerabilities faster than ever, potentially shifting the balance towards defenders if widely adopted. The dual-use nature of Mythos has created both panic and optimism in boardrooms and governments regarding global financial system security.

Bloomberg L.P.
Apr 17th, 2026
Indian fintechs push Anthropic for early access to 'dangerous' Mythos AI model

Indian fintech companies including One97 Communications, Razorpay Software and Pine Labs are pushing Anthropic for early access to Mythos, the AI model that has raised global concerns about cyberattack risks. The firms want to test Mythos on their own systems to detect vulnerabilities following Anthropic's announcement of a limited rollout. The San Francisco-based AI developer considers the model too dangerous for wider release but major Indian financial technology companies are seeking early access to assess potential security threats to their platforms.

Bloomberg L.P.
Apr 16th, 2026
US government prepares to give federal agencies access to Anthropic's Mythos AI model

The US government is preparing to provide major federal agencies with access to Anthropic's new AI model, Mythos, according to a memo reviewed by Bloomberg News. Gregory Barbaccia, federal chief information officer at the White House Office of Management and Budget, informed Cabinet department officials on Tuesday that OMB is establishing protections to enable agencies to use the closely guarded AI tool. The move comes amid concerns that the powerful model could significantly increase cybersecurity risks. OMB is working to set up appropriate safeguards before rolling out access to the system across government departments.

Bloomberg L.P.
Apr 16th, 2026
Anthropic's Mythos AI model raises cybersecurity alarms for banks and governments

Anthropic's new Mythos AI model is causing concern among banks, tech giants and governments over its potential implications for cybersecurity and the internet's future. The model has prompted a scramble amongst major institutions to understand its capabilities and risks. Details about the specific features raising alarms were not disclosed in the source material.

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