Zefr is the leading global technology company enabling responsible marketing in walled garden social environments. Our solutions let brands manage where their advertising shows up on YouTube, Meta, TikTok, and Snap, in line with industry-standard frameworks. Through patented AI technology, Zefr gives brands and agencies more accurate and transparent tools for social walled gardens. We're headquartered in Los Angeles, with additional locations across the globe.
What you'll do:Every AI system that can tell a cooking video from a combat video learned it from a person who made that call first. That person is you.
We're hiring a Multilingual Data Annotation Specialist to label video, image, and metadata content across YouTube, TikTok, Meta, and Snap, and to bring cultural fluency to calls that a model can't make on its own. A clip that reads as harmless in one market reads very differently in another. Catching that difference is the whole job.
Your labels become the ground truth our machine learning systems train on and get measured against. When you get a hard call right, the system gets better at it. When the guidelines don't cover the case in front of you, you're the one who tells us the guidelines need to change.
This role suits someone who finds ambiguity interesting rather than frustrating, who'd rather ask a sharp question than guess, and who takes real satisfaction in precision.
Here's what you'll get to do:Label social media content against Zefr's contextual category guidelines using our in-house tooling.
Make daily judgment calls on video, image, and metadata — including content where cultural and linguistic context changes the answer.
Apply labeling frameworks, then help us sharpen them when you find the gaps.
Spot emerging trends and edge cases early, and raise them before they become systemic mislabels.
Run root cause analysis on quality misses and turn what you find into process changes.
Perform lingual quality assurance across multiple project pipelines.
You'll also build a working understanding of machine learning and computer vision, and of exactly how annotation quality shows up in model performance.
What we're looking for:Language:Oral, written, and cultural fluency in Spanish and English is required.
Strong cultural fluency and a feel for context across varied content types.
Regular user of TikTok, YouTube, Facebook, Instagram, and Snapchat. You should know these platforms as a native, not a visitor.
Exceptional attention to detail, sustained across repetitive work.
Clear written communication, especially when explaining ambiguity, inconsistency, or definitional drift.
Comfort applying style guides and holding consistency across formats.
Comfortable using AI tools such as Claude, Gemini, or ChatGPT.
Proficiency in Google Workspace.
Background in annotation, content moderation, labeling, quality assurance, or policy enforcement.
SQL familiarity.
Additional languages — Portuguese, Mandarin, Turkish, Tagalog, or others — are a plus.
Comfortable reviewing sensitive content, including political topics, religious perspectives, violence, and adult material.
Reliable and coachable. You take feedback well and apply it quickly.
Analytical, with structured problem-solving instincts.
Steady in a fast-paced environment with shifting priorities.
Effective both on a team and on your own.
Sound judgment with confidential and proprietary information.
Able to work a hybrid schedule, 2–3 days per week in our Marina del Rey office.
This role involves regular exposure to sensitive content, including political and religious material, violence, and adult content. It's a real part of the work, and we'd rather you know that now than find out later. We provide guidelines, support, and a team that talks openly about the hard cases.
Benefits (for US based employees):Flexible PTO
Medical, dental, and vision insurance with FSA options
Company-paid life insurance
Paid parental leave
401(k) with company match
Professional development opportunities
10+ paid holidays off
Flexible hybrid work schedules
"Summer Fridays" (shorter work days on select Fridays during the summertime)
In-office lunches and lots of free food
Optional in-person and virtual events (we like to celebrate!)
The anticipated salary for this position is $72,400. Individual pay is determined by factors such as job-related skills, experience, and relevant education or training. If your compensation expectations fall outside of this figure, it may still be worth having a conversation.
Zefr is an equal opportunity employer that embraces diversity and inclusion in the workplace. We are committed to building a team that represents a variety of backgrounds, skills, and perspectives because we know this only makes us better. We strongly encourage women, persons of color, LGBTQIA+ individuals, persons with disabilities, members of ethnic minorities, foreign-born residents, and veterans to apply even if you do not meet 100% of the qualifications.
Skills Required
- Oral, written, and cultural fluency in Spanish and English
- Strong cultural fluency and contextual judgment across varied content types
- Regular usage and familiarity with TikTok, YouTube, Facebook, Instagram, and Snapchat
- Exceptional attention to detail during repetitive work
- Clear written communication when explaining ambiguity, inconsistency, or definitional drift
- Ability to apply style guides consistently across formats
- Comfort using AI tools such as Claude, Gemini, or ChatGPT
- Proficiency in Google Workspace
- Comfort reviewing sensitive content, including political, religious, violent, and adult material
- Reliability, coachability, analytical problem-solving, adaptability, teamwork, and independent work capability
- Sound judgment with confidential and proprietary information
- Ability to work a hybrid schedule two to three days per week in the Marina del Rey office
- Background in annotation, content moderation, labeling, quality assurance, or policy enforcement
- SQL familiarity
- Additional language proficiency, such as Portuguese, Mandarin, Turkish, or Tagalog
What We Do
Zefr is the leading data and technology company that enables responsible marketing for brands, agencies and platforms. The company leverages a patented AI and machine learning engine, called Cognition AI, to offer brands and agencies more accurate and transparent activation and measurement solutions on scaled video platforms.
Why Work With Us
As employees work to bring responsible marketing to the digital advertising ecosystem, we work to improve the lives of our employees both at work and at home. We are committed to building a team that represents a variety of different backgrounds, skills, and perspectives because we know this only makes us better.
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