Senior Multilingual Data Engineer - Scale Language Models

Reflection; San Francisco (CA); On-site; USD 140,000 - 210,000; Full time

Benefits offered by this job

Top-tier compensation and equity

Stock options for all contributors

Comprehensive health, dental, vision,

Meals provided in office

22 weeks parental leave

Unlimited PTO in US / 30 days in UK

Visa sponsorship

Team off-sites and celebrations

Job summary

Reflection in San Francisco seeks a research-focused engineer to design and operate large-scale multilingual data pipelines, sourcing, cleaning, deduplication, language identification, and script normalization across languages.

You will define quality bars for multilingual corpora, run experiments to scale language models, lead small projects, and collaborate with teams to improve multilingual capability while keeping ownership in a fast-moving environment.

Qualifications

• Strong software engineering fundamentals and experience processing large web-scale datasets.
• Experience building large-scale data pipelines for language models or NLP projects across multiple languages.
• Fluency or working proficiency in at least one language other than English; curiosity about language differences.

Responsibilities

• Design and operate large-scale multilingual data pipelines including sourcing, cleaning, deduplication, language identification and script normalization.
• Define and enforce quality bars for multilingual corpora focusing on translation quality, cultural fidelity, toxicity, and contamination checks.
• Design and run experiments to scale large language models and improve multilingual data efficiency.
• Lead small research projects independently and collaborate on broader initiatives.
• Build evaluation sets and diagnostics to expose model behavior gaps by language or domain and address them with data.
• Collaborate with pre-training, mid-training, and post-training teams to land measurable improvements in multilingual capability.

Skills

Software engineering

Distributed systems

Data pipelines

Multilingual NLP

Measurement mindset

Education

MS/PhD in CS/ML

Tools

Python

NLP toolchains

Cloud platforms

Job description

Reflection in San Francisco seeks a research-focused engineer to design and operate large-scale multilingual data pipelines, sourcing, cleaning, deduplication, language identification, and script normalization across languages.

You will define quality bars for multilingual corpora, run experiments to scale language models, lead small projects, and collaborate with teams to improve multilingual capability while keeping ownership in a fast-moving environment.