Who Are We? Welltech is a global wellness technology company with Ukrainian roots. Our mission is to build and scale wellness apps globally through state-of-the-art, tech-driven performance marketing. We are one of the most established players in the wellness app space, and we are accelerating. Over 25.5 million people across the world use our apps — Muscle Booster, Yoga-Go, and WalkFit — to build healthier habits, move more, and feel better every day. Every subscription represents a real person making a real change in their life, and we take that seriously. With 500+ people across hubs in Cyprus, Ukraine, Poland, Spain, and the UK, we combine the scale of a market leader and the drive of a team that's just getting started. What We're Looking For As a Senior Data Engineer, you will play a crucial role in building and maintaining the foundation of our data ecosystem. You’ll work alongside data engineers, analysts, and product teams to create robust, scalable, and high-performance data pipelines and models. Your work will directly impact how we deliver insights, power product features, and enable data-driven decision-making across the company. This role is perfect for someone who combines deep technical skills with a proactive mindset and thrives on solving complex data challenges in a collaborative environment. Challenges You’ll Meet: * Pipeline Development and Optimization: Build and maintain reliable, scalable ETL/ELT pipelines using modern tools and best practices, ensuring efficient data flow for analytics and insights. * Data Modeling and Transformation: Design and implement effective data models that support business needs, enabling high-quality reporting and downstream analytics. * Collaboration Across Teams: Work closely with data analysts, product managers, and other engineers to understand data requirements and deliver solutions that meet the needs of the business. * Ensuring Data Quality: Develop and apply data quality checks, validation frameworks, and monitoring to ensure the consistency, accuracy, and reliability of data. * Performance and Efficiency: Identify and address performance issues in pipelines, queries, and data storage. Suggest and implement optimizations that enhance speed and reliability. * Security and Compliance: Follow data security best practices and ensure pipelines are built to meet data privacy and compliance standards. * Innovation and Continuous Improvement: Test new tools and approaches by building Proof of Concepts (PoCs) and conducting performance benchmarks to find the best solutions. * Automation and CI/CD Practices: Contribute to the development of robust CI/CD pipelines (GitLab CI or similar) for data workflows, supporting automated testing and deployment. Required skills: * 4+ years of experience in data engineering or backend development, with a strong focus on building production-grade data pipelines. * 2-3+ years of experience working with AWS services (Administration of Redshift is a must), * Solid experience working with AWS services (Spectrum, S3, RDS, Glue, Lambda, Kinesis, SQS). * Proficient in Python and SQL for data transformation and automation. * Experience with dbt for data modeling and transformation. * Good understanding of streaming architectures and micro-batching for real-time data needs. * Experience with CI/CD pipelines for data workflows (preferably GitLab CI). * Familiarity with event schema validation tools/ solutions (Snowplow, Schema Registry). * Excellent communication and collaboration skills. Strong problem-solving skills—able to dig into data issues, propose solutions, and deliver clean, reliable outcomes. * A growth mindset—enthusiastic about learning new tools, sharing knowledge, and improving team practices. Tech Stack You’ll Work With: * Cloud: AWS (Redshift, Spectrum, S3, RDS, Lambda, Kinesis, SQS, Glue, MWAA) * Languages: Python, SQL * Orchestration: Airflow (MWAA) * Modeling: dbt * CI/CD: GitLab CI (including GitLab administration) * Monitoring: Datadog, Grafana, Graylog * Event validation process: Iglu schema registry * APIs & Integrations: REST, OAuth, webhook ingestion * Infra-as-code (optional): Terraform Bonus Points / Nice to Have: * Experience with additional AWS services: EMR, EKS, Athena, EC2. * Hands-on knowledge of alternative data warehouses like Snowflake or others. * Experience with PySpark for big data processing. * Familiarity with event data collection tools (Snowplow, Rudderstack, etc.). * Interest in or exposure to customer data platforms (CDPs) and real-time data workflows. Candidate journey: ⭕️ Recruiter call ➔ ⭕️ Technical call with the hiring manager ➔ ⭕️ Meet the future stakeholders Check out some of our products Muscle Booster — https://musclebooster.fitness/ Yoga-Go — https://yoga-go.io/ WalkFit -http://walkfit.pro