Japanese Language QA Lead — Contract

Cartesia; United States; Remote; USD 34,000 - 48,000; Full time

Benefits offered by this job

Health Insurance

Equity package

401(k)

Commuter Allowance

Flexible PTO

Meals & Snacks

Parental Leave

Job summary

Cartesia seeks a native-level Japanese language lead to own end-to-end language QA, data auditing, and project coordination for voice AI. You will work independently across multiple workstreams to ensure high-quality linguistic guidance and accurate annotations, influencing product performance.

The role is a 1099 contractor engagement with Roughly 40 hours per week, requiring availability during US Pacific hours for team syncs. In-office policy includes teams in SF, London, and Bangalore.

Qualifications

• Native-level proficiency in Japanese as spoken in Japan.
• Experience with data annotation, transcription, or language quality assurance.
• Strong foundation in linguistics or a related field, with the ability to apply concepts like phonetics, prosody, and intonation when evaluating speech and writing annotation guidelines.
• Strong written English proficiency. All guidelines, feedback, reports, and team communication are in English.
• Ability to write clear, structured instructions and deliver specific, actionable feedback to annotators.
• Comfortable working with data and metrics such as inter-rater agreement scores, audit spreadsheets, and structured feedback templates.
• Self-directed and able to manage feedback cycles, QA reviews, and data projects without close oversight.

Responsibilities

• Own language end-to-end tasks including auditing data and monitoring product performance.
• Coordinate with managers on project deliverables and timelines.
• Prepare written quality assessments with examples and recommendations.
• Listen to audio/TTS output and provide pronunciation and naturalness assessments.
• Develop onboarding materials and run calibration meetings with annotators.
• Write QA reports on annotation quality and calibration outcomes.
• Review production audio and flag quality issues; investigate language-specific customer feedback.

Skills

Native-level Japanese

Data annotation experience

Linguistics background

English proficiency

Instructional feedback writing

Data metrics & QA

Self-directed work

Education

Linguistics or Related Field

Job description

Cartesia seeks a native-level Japanese language lead to own end-to-end language QA, data auditing, and project coordination for voice AI. You will work independently across multiple workstreams to ensure high-quality linguistic guidance and accurate annotations, influencing product performance.

The role is a 1099 contractor engagement with Roughly 40 hours per week, requiring availability during US Pacific hours for team syncs. In-office policy includes teams in SF, London, and Bangalore.