At Stack Builders, we're looking for an AI Data Annotator to support the creation of high-quality datasets that power real-world AI systems.
This role is an entry point into AI and machine learning workflows, where you will build foundational skills in data quality, annotation, and structured processes that support production-grade systems. As part of our broader AI delivery pipeline, your work contributes to systems that continuously improve over time, not just one-time outputs.
You will work in a structured, collaborative, in-office environment alongside engineers and technical leads to produce accurate, consistent, and production-ready data used in computer vision, sports analytics, and robotics applications. Over time, this role can grow into opportunities in data quality, operations, and more advanced AI-related positions.
This is an entry-level, on-site role based in our Quito office.
IMPORTANT:
- To be considered for this position, please attach your CV in English.
- By applying to the job, you confirm you have read and accept our Ecuador Privacy Notice (also available at the bottom of this post). This is mandatory to be considered for our vacancy.
What You’ll Do
- Perform data annotation and labeling across images, video, and structured datasets
- Label objects, events, and behaviors using clearly defined guidelines
- Review and validate annotations to ensure accuracy, consistency, and completeness
- Follow structured workflows designed for high-quality AI training data
- Identify edge cases, ambiguous scenarios, and data inconsistencies
- Escalate unclear cases and contribute to improving annotation guidelines
- Collaborate with engineers and team leads to continuously improve dataset quality
- Improve annotation speed and accuracy over time through feedback and repetition
Projects You May Work On
Computer Vision
- Object detection and tracking
- Video annotation and event labeling
- Dataset preparation for model training and evaluation
Sports Analytics
- Athlete tracking and motion labeling
- Event detection (jumps, plays, movements)
- Performance analysis datasets
Robotics & Sensor Systems
- Scene and environment labeling
- Multi-frame and multi-sensor annotation
- Safety-critical dataset validation
Requirements
- A Professional level of English is required (B2)
- Bachelor’s degree in Computer Science, Information Technology, Mathematics, or a similar field
- Strong attention to detail and consistency
- Ability to follow structured instructions and guidelines precisely
- Reliable, organized work habits
- Willingness to learn and improve through feedback
- Comfortable working with computers and web-based tools
- Ability to work on-site in the Stack Builders Quito office
Nice to Have (Not Required)
- Interest in AI, machine learning, or data systems
- Experience with data entry, QA, or annotation tools
- Familiarity with images, video, or digital media
What Success Looks Like
- Create a substantial amount of annotations daily
- High accuracy and consistency in labeled data
- Strong attention to edge cases and ambiguity
- Measurable improvement in speed and quality over time
- Clear communication when something is unclear
- Contributions to datasets that engineers can confidently use in production systems
What You’ll Gain
- Hands-on experience with AI and machine learning workflows
- Exposure to real-world applications in computer vision, sports, and robotics
- Experience working alongside engineers and technical teams
- A strong foundation for future roles in data, QA, or AI-related fields
Why This Role Matters
AI systems are only as good as the data they learn from.
Your work directly impacts how models perform in real-world environments by ensuring the data is accurate, consistent, and reliable. This role is a key part of building AI systems that improve over time, not just once.
Benefits
- A certified Great Place to Work culture!
- A strong learning culture with regular 1:1 sessions with your manager, and training.
- Quarterly Employee Assessments Cycles to keep track of your career advancement and skill development.
- Top-tier private health and dental insurance.
- Mental health assistance bonus (subject to policy and after trial period).
- 7 days of annual vacation, paid time off for sick days, and parental and family leave.
- Quarterly virtual and in-person team-building activities, birthday and holiday celebrations, and other special events.
- Exciting and impactful projects from different industries leveraging various tools and technologies.
- A Welcome Package on your first day with a Stack Builders laptop and additional equipment.
--
More than our EEO statement, this is what makes us a Great Place to Work:
Stack Builders is proud to be an equal opportunity employer. We are committed to creating a safe and inclusive work environment and don’t tolerate discrimination or harassment during the hiring process or time of employment.
All team members and candidates are assessed and appreciated for their attitude, qualifications, and potential - regardless of race, religion, color, nationality, sexual orientation, gender expression or identity, age, disability, marital status, pregnancy, and other characteristics protected by law.
You can learn more about us by visiting our website, or taking a look at our community content.
--
Aviso de Privacidad Stack Builders Ecuador:
Al postular a nuestras vacantes en Ecuador, usted confirma que ha leído y acepta nuestro Aviso de Privacidad de Ecuador.
CLÁUSULA INFORMATIVA PARA TRATAMIENTO DE DATOS DE CANDIDATOS
1. Datos del responsable del tratamiento:
- SBIE CONSULTORÍA DE SOFTWARE CIA. LTDA (en adelante STACK BUILDERS)
- Dirección: Av. Amazonas E3-39 y Av. Naciones Unidas, Edif. La Previsora, piso 10, ofic. 1002, Quito
- RUC: 1792443253001
- Teléfono: 02-401-6115
- Correo electrónico: dataprivacy@stackbuilders.com
2. Finalidades:
En STACK BUILDERS tratamos la información que nos facilita con el fin de analizarla para el cargo pretendido y mantenerle informado de las distintas vacantes a un puesto de trabajo que se produzcan en nuestra organización.
3. Conservación:
Los datos proporcionados se conservarán hasta la adjudicación de un puesto de trabajo o hasta que usted ejerza su derecho de supresión o eliminación.
4. Cesiones:
Los datos no se cederán a terceros salvo en los casos en que exista una obligación legal.
5. Ejercicio de derechos:
Usted tiene derecho a obtener información sobre si en STACK BUILDERS estamos tratando sus datos personales, por lo que puede ejercer sus derechos de acceso, actualización, rectificación, eliminación, portabilidad de datos, oposición y limitación a su tratamiento ante STACK BUILDERS, a la dirección de domicilio señalada al inicio, o en la dirección de correo electrónico dataprivacy@stackbuilders.com , adjuntando copia de su documento de identificación.
Si considera que su requerimiento no ha sido satisfecho, podrá presentar una reclamación ante la autoridad de control de protección de datos.