Retell AI

Senior Language Engineer

San Francisco Bay Area · Senior

Sponsorship not specified$200k-$290kDetected 14 days ago

Machine LearningData EngineeringNLPNegotiationLogisticsResearch

About the role

You will play a critical role in driving modeling innovation, working closely with researchers, ML engineers, and product managers to ensure our AI systems sound natural, humanlike, and aligned with human preferences.

Define requirements and own the end-to-end pipeline for creating high-quality datasets for voice agent use cases, across both text and audio modalities.
Coordinate and manage a human annotation workforce: author guidelines, define quality targets, and QA annotator output.
Partner with researchers and engineers to drive each modeling iteration.
You will own the full data stack, from data creation, scraping, and synthesis, to managing an annotation workforce, to data cleaning, processing, evaluation, and analysis, applying sharp linguistic judgment throughout.
Let's build the future together.

2+ years of experience in computational linguistics, language data processing, or a similar field, including hands-on work with large-scale text and audio datasets.
Thousands of companies now utilize Retell's AI voice agents to handle sales, support, and logistics calls that once required large teams of human agents.

Native-level command of English, with the confidence to make opinionated linguistic calls about what sounds natural in voice agent conversations.
A strong applied ML background in language or audio modeling - ideally having contributed to the data pipelines behind a well-known audio or language model.
A PhD in Computational Linguistics or an equivalent field with computational emphasis.
Experience managing human annotation and evaluation teams.

100% coverage for medical, dental, and vision insurance
$200/month wellness reimbursement (gym, fitness classes, etc.)
$300/month commuter reimbursement (gas, Caltrain, etc.)
$75/month phone bill reimbursement
$50/month internet reimbursement
Our vision for 2026 is to build a modern CX platform where entire contact centers are powered by AI.
Equity Provided
Small teams, >$1M revenue/employee, and significant equity.
Build data processing and cleaning pipelines that align datasets to production needs, balancing coverage across use cases, languages, and domains.

Retell AI is open to sponsoring work authorization for qualified candidates, including H1B/H-1B, TN, L-1, E-3, F-1 (OPT/CPT).

This listing is sourced directly from Retell AI's careers page and normalized into a canonical job model.