Senior Fullstack Engineer

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Senior Full-Stack Engineer

Location: Remote from Colombia

.Monks Technology Services, part of Media.Monks and S4 Capital, is a global consulting firm mastering AI-powered transformations for the Fortune 100. We combine long-term strategic thinking, deep enterprise experience, and a human-centered approach to help clients transform business processes and dominate their industries.

About the Role

As a Senior Full-Stack Engineer, you’ll build an in-house platform that helps battery engineers ingest, explore, and act on test data. The platform transforms raw equipment output into a consistent data model, supports qualification decisions through interactive charts and dashboards, and provides an AI assistant grounded in the same data. You’ll own features end to end-from the first stakeholder conversation through data models, APIs, and user interfaces-with substantial autonomy. As the platform replaces tools engineers rely on daily, you’ll help earn their trust through accuracy, traceability, and a thoughtful rollout.

Responsibilities

• Design and build Python backend services, REST APIs, data access layers, and background jobs for ingestion and long-running computations.
• Develop robust parsers that transform vendor files, CSVs, and binary exports into validated records, handling inconsistent headers, changing units, and malformed inputs with clear rejection reasons.
• Implement traceable data transformations for capacity, efficiency, resistance, and cycle aggregates, ensuring consistent results across pipelines and on-demand calculations.
• Build React and TypeScript interfaces with interactive charts for large time-series datasets, including millions of points, cross-cell and cross-test overlays, and detail-preserving zoom.
• Integrate an AI assistant using LLM APIs, tool calling, and retrieval over platform data and documentation, with citations and evaluations that identify incorrect answers.
• Work directly with test engineers, lab supervisors, and upstream data owners to clarify needs, scope deliverables, and explain technical trade-offs.
• Own technical decisions across the data model, API, and user experience, delivering features from discovery through production with minimal oversight.
• Implement production observability using structured logging and request correlation, and support reliable delivery through Docker and GitLab CI.
• Maintain rigorous tests, strict typing, small reviewable changes, and accurate documentation while avoiding premature abstraction.
• Support an incremental transition from existing tools without disrupting engineers’ daily workflows.
• Other duties as assigned

About You

Qualifications & Skills

• 6+ years of experience building production software, with substantial experience across both backend and frontend development.
• Strong Python backend skills, including REST API design, asynchronous services, background processing, authentication, authorization, and performance tuning under real load.
• Experience with relational data modeling, fluent SQL, and schema migrations in live systems.
• Hands-on Python data processing experience with pandas, Polars, or NumPy.
• Strong modern TypeScript and React skills.
• Experience shipping interactive data visualizations to real users, ideally with large or time-series datasets.
• Experience building parsers and transformation pipelines for messy real-world data, including vendor formats, schema drift, partial files, and unit handling.
• At least one LLM integration shipped in a product, including prompt design, tool or function calling, retrieval, and a method for evaluating output quality.
• A track record of leading requirements conversations with non-engineers and translating them into scoped deliverables, supported by concrete examples.
• Demonstrated autonomy through projects you have scoped, built, and shipped with minimal oversight.
• Strong communication skills and English proficiency at B2 level or above.

Preferred Qualifications

• Experience with FastAPI, Pydantic v2, SQLAlchemy 2.x, and asynchronous Python at scale.
• Familiarity with a Python 3.12 toolchain using pytest, uv, Ruff, and mypy in strict mode.
• Background in battery technology, hardware testing, lab information management, or manufacturing data.
• Experience optimizing time-series workflows through downsampling, columnar formats such as Parquet or Arrow, or GPU-accelerated or canvas rendering.
• Experience with production RAG or agent systems, including evaluation and guardrails.
• Experience working with scientific or engineering data where derived metrics inform consequential decisions.
• Experience replacing a legacy system through incremental adoption rather than a hard cutover.

.Monks Technology Services does not discriminate on the basis of race, sex, color, religion, age, national origin, marital status, disability, veteran status, genetic information, sexual orientation, gender identity or any other reason prohibited by law in provision of employment opportunities and benefits.

At .Monks Technology Services, we believe in fostering an environment where a diversity of perspectives can thrive. We proactively work to design hiring processes that promote equity and inclusion while mitigating bias. We celebrate diversity and are committed to building a team that reflects the communities we serve. We welcome and encourage qualified applicants, from all backgrounds, who are excited to contribute to our mission.

Unsure if your skills meet all of our requirements?

Apply anyway! We would love to learn more about you and find out about how your skills could add value. At .Monks Technology Services we value open communication and feedback. We believe that diversity of identity, perspective, and experience makes us stronger; we would love to hear your perspective too!

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About Monks

Monks is the global, digital-first, data-driven, unitary operating brand of S4Capital plc, where our culture centers on how we show up for the work and for one another. That begins with the commitment to strive for mastery-taking deep pride in our craft and creating work that sets the bar. In everyday execution, we drive momentum by choosing bold action rather than waiting for certainty. Above all, our teams are stronger together, bringing diverse perspectives into a unified team that communicates with clarity, trust, and mutual respect.

This commitment to craft and innovation translates directly into widespread industry acclaim: Monks was named a Contender in The Forrester Wave™: Global Marketing Services and a leader in the 2026 Gartner® Magic Quadrant™ for Global Digital Marketing Agencies. It ranks among Cannes Lions' Top 10 Creative Companies (2022-25) and remains the only partner featured in AdExchanger’s Programmatic Power Players list every year (2020-24). Named Adweek’s first AI Agency of the Year (2023) and The One Show’s inaugural AI Pioneer Organization (2025), Monks was also awarded Business Intelligence Group’s 2026 Excellence in Artificial Intelligence Award in the Human-Machine Interaction Team category. Additionally, Monks.Flow earned AI-based Marketing Solution of the Year at the 2026 AI Breakthrough Awards and a 2026 Global Generative AI Award in the Agentic Marketing Innovation category. Finally, Monks achieved a record-breaking number of FWAs and continues to hold the most of any partner.

We are an equal-opportunity employer committed to building a respectful and empowering work environment for all people to freely express themselves amongst colleagues who embrace diversity in all respects. Including fresh voices and unique points of view in all aspects of our business not only creates an environment where we can all grow and thrive but also increases our potential to produce work that better represents-and resonates with-the world around us.