Jeferson – React, Node.js, Typescript

This is an innovative AI-first platform dedicated to creating custom reinforcement learning (RL) environments for training advanced AI models. The primary users are AI researchers, developers, and teams building next-generation intelligent agents that learn through trial-and-error interactions in simulated settings. Core functionality includes procedurally generating dynamic RL environments (defining states, actions, rewards, and transitions), enabling scalable model training via interaction-based learning, and integrating AI-driven code generation to accelerate development. The project embodies the future of software engineering, where AI handles the majority of code creation under optimized rules and commands, maximizing efficiency and automation while maintaining high standards through human oversight.

• He ensures the quality of AI-generated code deliveries by implementing rigorous end-to-end (E2E) tests, significantly reducing regressions, enhancing overall reliability, and successfully maintaining high delivery standards in a fully AI-generated codebase.
• He continuously improves code quality through in-depth reviews, targeted refactoring guidance, and strict enforcement of best practices within an AI-heavy development workflow.
• He mentors new team members, accelerating their onboarding and ramp-up in a cutting-edge, fast-paced AI-first environment by sharing expertise on optimization rules, command structures, and effective human-AI collaboration techniques.
• He contributes to refining development workflows by focusing on advanced rules and commands that enable maximum optimization, productivity, and scalability in AI-assisted coding—playing a key role in realizing a visionary paradigm where AI handles nearly all code generation, with human emphasis on quality gates, strategic improvements, and positioning the project as a forward-looking example of future software engineering.

Brazilian AI-first technology company specializing in artificial intelligence solutions for customer service. Drawing from over two decades of experience in software development and process automation, the platform transforms business communication by using natural language as the primary bridge between people and systems. Primary users are businesses (from small to enterprise) and their end-customers, who interact via messaging channels (e.g., WhatsApp, web chat) for support, inquiries, and transactions. Core functionality includes intent understanding from natural language inputs, orchestration of action chains (e.g., API calls, data retrieval, responses), reliable message handling to prevent loss, real-time LLM behavior correction, and seamless automation of repetitive service tasks to enable faster, more accurate, and scalable customer interactions.

• He built the entire AWS infrastructure from scratch, designing a resilient, scalable cloud environment that supported the platform's complete growth from MVP to stable production launch without any downtime or data loss, establishing robust foundations for natural language-driven automation in a high-stakes customer service setting.
• He engineered a highly resilient messaging and action orchestration system that eliminated risks of massive message loss during high-volume interactions or transient failures, achieving critical high availability and reliable processing under peak loads for real-time customer service demands.
• He developed the core AI engine end-to-end, which accurately understood user intent from natural language, translated it into executable chains of actions across integrated systems, and guaranteed reliable request execution—enabling seamless translation of user queries into automated workflows and positioning the platform as a transformative tool for Brazilian businesses in customer communication.
• He implemented an innovative real-time penalty and feedback system for the LLM, which enabled rapid detection and correction of incorrect behaviors, dramatically improving response accuracy, reducing errors in live interactions, and significantly enhancing the quality and trustworthiness of AI-generated responses.

Scalable web platform that connects professional and aspiring athletes with clubs, agents, scouts, sponsors, and other professionals in the global sports industry. Its core users are athletes (amateur to pro across various sports), who can showcase their profiles, skills, and performance data, as well as receive assessments and opportunities to advance their careers. The platform enables networking, visibility, and direct connections in the sports ecosystem.

• He migrated the entire codebase from JavaScript to TypeScript, adding static typing that reduced runtime errors by 60% and sped up team onboarding.
• He led the zero-downtime infrastructure migration across AWS accounts, redesigning IAM roles, VPC peering, resource tagging, and implementing AWS CDK for infrastructure as code.
• He designed and deployed a reliable CI/CD pipeline using GitHub Actions to automate builds, tests, and deployments.
• He containerized the full stack with Docker and migrated it to Amazon ECS with Fargate, removing single points of failure.
• He configured auto-scaling based on CPU usage and custom CloudWatch metrics, allowing the system to support 3x more concurrent users without performance degradation or increased costs.
• He contributed to the early planning and design of a new, more modular system architecture to enable easier future scaling and feature expansion.

High-scale, cloud-based creative SaaS platform that empowers marketers, designers, and agencies to create and publish no-code interactive digital experiences (e.g., animated infographics, microsites, landing pages, reports, and immersive content). Primary users are enterprise marketing teams and creative professionals at leading brands, who build engaging, responsive content that drives attention, engagement, and action across devices. Core functionality includes a drag-and-drop studio for real-time collaborative design, animation tools, analytics for engagement metrics, global CDN delivery, and integrations for seamless publishing and e-commerce.

• He boosted product performance, maintainability, and feature velocity by migrating legacy Backbone.js modules to modern React components, enhancing reliability and enabling faster development cycles across the platform.
• He significantly improved platform accessibility for enterprise clients by implementing comprehensive keyboard navigation and resolving screen-reader compatibility issues in auto-generated interactive content.
• He accelerated backend modernization as a core contributor to the NestJS microservices architecture, replacing outdated legacy services with scalable, message-driven APIs that supported higher loads and better separation of concerns.
• He raised engineering quality standards by enforcing ~100% API documentation coverage through TypeScript decorators combined with custom ESLint rules, ensuring consistent, self-documenting codebases.
• He reduced defects and increased release confidence by systematically introducing automated unit, integration, and end-to-end (E2E) tests across critical paths.
• He mentored engineers and elevated team productivity through detailed code reviews, architectural guidance, and establishment of contribution standards in a collaborative environment.
• He cut cloud and local development costs substantially by replacing VMWare-based environments with standardized Docker containers, streamlining developer setups and reducing infrastructure spend.
• He shortened deployment cycles by optimizing Jenkins pipelines and container build processes in the monorepo, improving overall delivery speed.
• He enabled scalable global content delivery by contributing to the migration from Fastly to Cloudflare CDN, including automated service configuration via Terraform for dynamic routing and policies.
• He maintained and optimized VCL logic for advanced caching, dynamic backend routing, and performance tuning to deliver faster site experiences.
• He validated horizontal scalability of the legacy ShareJS real-time collaboration layer through a successful proof-of-concept, providing critical guidance for future architectural decisions.

An early large-scale conversational AI tutoring platform powered by IBM Watson, designed for EdTech and corporate learning environments. Primary users included students, learners, educators, and corporate training programs. Core functionality centered on dialog-based interactions using natural language processing to deliver personalized, adaptive tutoring experiences that boosted engagement, learning personalization, and efficiency in educational and training scenarios.

• He contributed to one of the company's first large-scale AI initiatives by developing features for an IBM Watson-powered dialog-based tutoring system, boosting student engagement, personalization, and product differentiation through conversational AI interactions.
• As part of the CI/CD team, he prepared the infrastructure structure and pipelines to reliably run and deploy the tutoring system on AWS, enabling scalable cloud operations and consistent releases for the AI-driven EdTech product.
• He achieved substantial reductions in infrastructure costs through resource consolidation and shared-instance models.

An enterprise HR platform was a legacy system built on Adobe Flex, serving large organizations, HR teams, and enterprise environments for managing core HR processes such as employee lifecycle, onboarding, performance management, and compliance workflows. The project focused on modernizing this legacy application into a contemporary web-based architecture to achieve superior performance, maintainability, scalability, and long-term viability in high-volume enterprise HR settings.

• He led a critical application modernization effort by migrating legacy HR platform from Adobe Flex to AngularJS, significantly improving maintainability, performance, development velocity, and long-term supportability for enterprise HR processes.
• He supported architecture decisions, code quality, and maintainability through in-depth performance reviews, design guidance, and implementation of best-practice patterns that enhanced readability and reduced technical debt.
• He improved software reliability, reducing costs, and streamlining development, adding a solid test strategy.

Leading Brazilian digital entertainment and gaming company that published and operated high-traffic online games (including MMORPGs like Ragnarok Online), managed e-commerce for digital goods, community forums, and supporting web platforms serving millions of users across LATAM. Primary users were gamers, community members, content teams, and internal operations staff. Core functionality included scalable web/e-commerce frontends, content management systems (CMS), real-time game integrations, billing/payment gateways, large-file delivery, behavioral tracking for marketing insights, and robust infrastructure for performance under heavy load.

• He led the development of core web and e-commerce platforms, delivering new features and modernizing legacy systems with PHP, .NET Framework, AngularJS, and Yii frameworks, which greatly improved stability, user experience, and scalability for millions of daily active users.
• He designed and built scalable CMS and internal tools that dramatically reduced manual workload for content teams and accelerated time-to-publish for game updates, promotions, and community content.
• He enhanced system performance and reliability by optimizing Nginx/Varnish configurations, implementing advanced cache strategies, and tuning backend services across multiple high-traffic applications.
• He modernized authentication flows by integrating secure ASP.NET MVC token-based services with PHP applications, boosting overall security, seamless cross-product login experiences, and user trust.
• He reduced operational overhead by developing custom dashboards, monitoring tools, and incident-response integrations that provided real-time visibility into system health and significantly sped up troubleshooting and recovery.
• He streamlined development workflows by implementing continuous integration with Jenkins and enabling blue-green deployments, allowing safer, faster, and more frequent releases with minimal risk.
• He executed critical migrations, including shifting the community forum from C# to vBulletin and upgrading multiple legacy systems, all completed with minimal downtime and no major disruptions to users.
• He built data and behavioral tracking APIs that empowered marketing and product teams to collect actionable insights, optimize campaigns, and drive better user retention and monetization.
• He elevated developer productivity and code quality by mentoring team members on SOLID principles, best practices, and test-driven development, fostering a stronger engineering culture.
• He supported mission-critical systems such as billing, payment gateways, and large-file delivery tools, ensuring high performance, reliability, and uptime during peak high-volume operations.