José Geraldo de Lima Júnior
I'm a Senior Android Engineer with over 8 years of experience, working across multiple industries (mostly Consumer Electronics and Retail Automation) and with globally recognized clients. I've developed and maintained large-scale Android applications using Kotlin and Java, and have strong expertise in Jetpack Compose, RESTful integrations, and app architecture patterns like MVVM and MVI. I also have experience with fullstack development, cloud, and IoT.
Most recently at Jobsity, I’ve been working in a complex SDK used by hundreds of thousands of users, rebuilt the entire UI SDK, redesigned API integrations to improve performance, and modernized the delivery and release system with Maven. With those changes, I was able to reduce the SDK integration time from weeks to hours, since now the customers have an easy and well-documented way to do it. I've also led teams of up to 9 people, handled architectural decisions, and mentored junior engineers in both Android and cross-platform development. And with the AI evolution, I've been using LLM to assist development in the last year, improving my productivity in 10x. I take pride in delivering quality code fast—something that I think it aligns well with any companies mission.
REVIEWS FROM CLIENTS
· Contributed to the development of a product serving 30,000+ users within a 7-person team, including 1 QA, managing a codebase of ove...
· Contributed to the development of a product serving 30,000+ users within a 7-person team, including 1 QA, managing a codebase of over 70,000 lines and 250 classes.
· [2026] Contributed to the development of a new product initiative consisting in new Android social app to show off our SDK capabilities, from ground zero, using modern technologies like Jetpack Compose, Koin, Material, coroutines, Gson, OkHttp and Retrofit
· [2026] Contributed with internal AI initiatives, training agents to work on an MCP used by the company’s AI Assistant to help developers to integrate our SDK easily or to fix bugs
· Delivered features and bug fixes in 2-week sprints with a personal velocity of 6 items per sprint, ensuring timely and efficient releases.
· Independently developed 5 new features and maintained 5 legacy features, demonstrating expertise in handling complex, legacy codebases.
· Rebuilt the entire UI SDK, introducing new designs and features, and modularized it into an independent component for improved scalability and usability.
· Redesigned and implemented the complete RESTful API integration using Retrofit and OkHttp libraries, enhancing performance and maintainability.
· Contributed on the re-writing from ground zero of a product written in React-Native to native Android serving 5,000+ users within a ...
· Contributed on the re-writing from ground zero of a product written in React-Native to native Android serving 5,000+ users within a 2-person (mobile) team, including 1 iOS engineer
· Delivered features in 2-week sprints with a personal velocity of 6 items per sprint, ensuring timely and efficient releases, with environment-aware builds, documented solutions, and consistent release process.
· Independently developed 4 new features (offline-first support, onboarding, microphone management, and rich text editor) and reimplemented 6 legacy features (voice recording, phone call, etc), demonstrating expertise in handling complex, no-documented codebases.
· Mastered development using AI-first approach, developing skills, rules, and agents to build solutions reliably based on strong and well-defined technical requirements, aiming scalability, performance, and maintainability.
· Contributing to the development of 2 products serving over 1mm users each, within a 10-person team, including 3 QAs, managing a code...
· Contributing to the development of 2 products serving over 1mm users each, within a 10-person team, including 3 QAs, managing a codebase of over 150,000 lines and 420 classes. Delivering features and bug fixes in 2-week sprints with a personal velocity of 6 items per sprint, ensuring timely and efficient releases.
· Building 23 new features and maintaining 5 other legacy features, demonstrating expertise in handling complex, legacy codebases. Creating a new app version from scratch in React Native while maintaining the native Android one, including new screens, integrations and UX flows. Implementing backend APIs, database models and queries, and web frontend to integrate with them, improving scalability, usability, and interoperability.
· Building custom Android image features for POS machines, to connect it to a cloud server where they could be set up and managed remotely. Integrated IoT APIs using MQTT protocols, ensuring efficient and secure communication.