About

Pedro H. S. Santos

Ponte de Lima, Portugal | pedro357bm@gmail.com | LinkedIn

Work Experience

WhyHow AI — Tech Lead (Remote, 11 mo)

A Legal Tech company driven by AI that detects early signals to support legal cases.

• Led the adoption of LLM-powered development workflows, introducing code agents that reduced MVP development time by ~40% and enabled rapid experimentation across multiple product initiatives.
• Owned end-to-end delivery of AI-driven products, from ideation to production, shipping multiple MVPs and establishing a data-driven experimentation culture.
• Designed and implemented RAG-based pipelines to process and analyze large-scale legal datasets (100k+ documents/month), generating automated reports that reduced manual analysis time and improved consistency.
• Built a robust LLM evaluation framework (G-Eval, LLM-as-a-judge) using Chain-of-Thought prompting, increasing output reliability and enabling systematic model iteration.
• Reduced LLM operational costs by ~30-40% through usage monitoring, prompt optimization, and intelligent request routing.
• Architected cloud infrastructure using Terraform (IaC) across AWS and Google Cloud, reducing environment provisioning time from hours to minutes.
• Contributed to a production-grade serverless architecture (AWS Lambda, Fargate, SQS) handling asynchronous workloads at scale.
• Designed high-throughput data ingestion systems (queue-based + multi-threaded scraping), enabling reliable collection and processing of large external datasets.
• Improved CI/CD pipelines, reducing deployment time from ~30 minutes to <5 minutes.
• Partnered directly with stakeholders and founders to translate ambiguous business ideas into testable MVPs, defining success metrics that drove key product pivots.

Lemon.io — Senior Software Engineer, Contractor (Remote, 2023-2025)

Lemon.io gave me the opportunity to work closely with small and medium-sized start-ups to help them improve their products and processes.

Tech Drug — Pharmacy Drug Development with AI

• Contributed across backend and frontend systems, rapidly building full product context and accelerating delivery of cross-functional features.
• Maintained and evolved a core RAG-based workflow responsible for generating clinical study reports, improving output consistency and system reliability.
• Owned the “AI Suggestions” feature end-to-end, designing evaluation pipelines to assess and enhance generated clinical studies.
• Designed improvements to retrieval and ranking strategies within RAG pipelines, increasing relevance of generated outputs and reducing noise.
• Collaborated with the Data Engineering team, integrating Snowflake datasets to power new AI-driven features.
• Developed and maintained backend services using Django and GraphQL, improving API performance, schema design, and maintainability.
• Strengthened integration and end-to-end testing strategies, reducing regressions and increasing confidence in production releases.

TrueLogic — Senior Software Engineer, Contractor (Remote, 2022-2023)

Worked as a contractor to help start-ups build and validate new products quickly, reducing time-to-market.

Big American News Website

• Led the backend modernization initiative, migrating a legacy Django monolith to a high-performance Go-based architecture for a high-traffic news platform.
• Designed and implemented a Go-based core API supporting millions of monthly users with improved latency and throughput.
• Built a high-performance reverse proxy service in Go to manage URL migrations and redirects, ensuring SEO preservation during large-scale content restructuring.
• Engineered systems to handle high-traffic workloads (tens of millions of monthly visits), optimizing routing, caching strategies, and request handling.
• Collaborated with cross-functional teams to redesign backend services powering content publishing and newsletter workflows.
• Implemented robust redirect and routing logic to handle evolving content URLs at scale, minimizing broken links and preserving traffic continuity.

Navegg — Tech Lead (Remote, 2019-2022)

The Latin American market leader in big data, DMP solutions, and analytics for retargeting, lookalike, BI, and programmatic media strategies.

Tech Lead

• Led a team of 4 engineers in the design and development of a large-scale Customer Data Platform (CDP), processing behavioral data and enabling audience segmentation for programmatic advertising at scale.
• Architected the migration from a monolithic system to a microservices architecture, defining service boundaries and enabling independent scaling.
• Designed and implemented event-driven microservices using Apache Kafka, supporting high-throughput data ingestion and real-time processing of user events.
• Built and scaled systems handling millions of daily tracking events (tag manager infrastructure), ensuring low-latency ingestion and reliable downstream processing.
• Designed a high-performance REST API for a tag management system, optimizing query performance under high concurrency (~1M+ monthly requests).
• Engineered distributed data pipelines for real-time audience segmentation and analytics.
• Worked extensively with NoSQL databases, optimizing data modeling, indexing strategies, and query performance for large-scale datasets.
• Delivered infrastructure cost analysis and optimization strategies, enabling safe system scaling while reducing cloud spend.
• Mentored engineers on microservices architecture, event-driven systems, and data engineering principles.

Senior Full-stack Developer

• Mentored junior developers to ensure quality and compliance across teams.
• Conducted dailies, planning, and retros.
• Planned features and products with PMs and stakeholders.

Full-stack Developer

• Developed internal packages shared among microservices written in Go and Python (RabbitMQ, PostgreSQL, Kafka connectors).
• Guided the development cycle, reviewed PRs, and mentored junior developers.
• Developed apps with React.js and TypeScript.
• Worked on the backend to implement and maintain features across products.

Before 2019

Worked for many companies since 2016, when I got my first job as a full-stack junior developer.

Education

UFF University — Rio de Janeiro, Brazil

BS, Computer Science (GPA: 6.1/10) — Graduated 2019

FullCycle — Remote, Brazil

MBA in Solutions Architecture — In Progress

Skills

Python Go TypeScript React FastAPI Django GraphQL PostgreSQL MongoDB DynamoDB Redis Apache Kafka RabbitMQ AWS Google Cloud S3 SQS Lambda API Gateway Fargate ECS Kubernetes Docker Terraform GitHub Actions CI/CD Snowflake Datadog New Relic Langfuse LangChain RAG LLM Evaluation Prompt Engineering OpenAI Reducto Sentry Grafana Linux

Certificates

• Containers Fundamentals (LFS253) — Linux Foundation, 2024
• Linux for Cloud Technicians Essentials (LFS203) — Linux Foundation, 2024