# Juan Hernandez > Senior Software Engineer @ OfferUp Location: Miami, Florida, United States Profile: https://flows.cv/juanhernandez Experienced Client Developer with more than seven years of experience working in the computer software industry. Skilled in the Web platform with React and in the mobile platform with React Native and Android. ## Work Experience ### Senior Software Development Engineer @ OfferUp Jan 2021 – Present | Miami/Fort Lauderdale Area OfferUp App: • Engaged in the release processes and contributed to the automation of weekly releases to the stores, enabling us to iterate faster on experiments and new features we were launching. • Contributed to the OfferUp Jobs initiative by delivering features using 100% test-covered components from our built-in-house library, launching before expected and with an insignificant amount of bugs. • Fixed critical bugs affecting Android users' experience and causing a lot of bad reviews in the Google Play store and amount of ANRs. • Collaborated on the initiative to start using the built-in-house library components in our React Native apps to have a consistent style across the different areas of our apps. ### Software Development Engineer @ OfferUp Jan 2019 – Jan 2021 | Miami/Fort Lauderdale Area OfferUp For Business: • Quickly adapted to technology use changes in the company and started developing Web apps using React. • Built a Web portal from scratch for merchants to create their profile in OfferUp and integrate their multi-channel listers (like ChannelAdvisor) to increase B2C transactions in the app. • Added unit and integration tests to the Web portal from the beginning reaching more than 80% code coverage which allowed us to deliver on time with a small number of bugs. • Lead the QA engineers to write integration tests using Cypress to have our UI test covered as well and avoid undesired changes in our UI when making changes in the base code. • Integrated Stripe React SDK to capture financial information from merchants. • Integrated Google Recaptcha in the authentication flow to avoid scams and bots flooding our server. • Used the same Merchant Portal codebase to transition to Local Ads Portal, making the business pivot smooth, and launching the new Portal quickly. OfferUp Web App: • Re-built the OfferUp Web App from scratch using components from a library built in-house based on Material UI to give the offerup.com site a new and fresh look to boost engagement and use of the Web app. • Contributed to the built-in-house component library with payment components, authentication forms, and others, to allow the use of these across our client apps including the OfferUp For Business Web app. • Wrote unit and integration tests for the component library and the Web App to match the 100% coverage threshold established and to allow us to ship regression-protected and bug-free features. • Worked in strong collaboration with the Product and Design team, making contributions to improve the user experience and our onboarding flows. ### Android Developer @ Applicaster Jan 2018 – Jan 2019 | Miami/Fort Lauderdale Area • Developed and maintained several media stream services apps for clients like Televisa, TYC, HITN, TvGo, Olympic Channel, and others. • Built authentication libraries (using AWS Cognito, Adobe Primetime Authentication, and others) and analytics libraries (using Chartbeat, Clevertap, and others), enabling integration into existing and future apps. • Worked in a fast-paced environment where deadlines were attached to international events like the Copa America Tournament, strengthening my ability to find and fix bugs in a short time slot. • Attended the Google I/O 2019 conference and share with our Android development team the latest news and experiences taken in the event. • Lead the initiative in our LATAM team to start adopting Kotlin in our codebase to stay up to date with the Android latest technologies. ### Creative Director and Lead Android Developer @ Viera Academy Jan 2016 – Jan 2017 | Miami/Fort Lauderdale Area Designed, coded, and built an Android app to help students connect and book on-demand Viera Academy Certified Tutors. • Designed the entire app using Sketch and Invision following the guidelines of material design. • Implemented push notifications and customer engagement systems using the Google Firebase platform. • Optimized application performance by using the Model View Presenter (MVP) architectural pattern in the development of the app. • Collaborated with the team to design and develop RESTful APIs. • Integrated Retrofit library as an HTTP client to improve communication with Backend APIs. • Designed payment solution by integrating Stripe software SDK. ### Co-founder and Lead Android Developer @ Ke hay pa hoy? Jan 2015 – Jan 2016 | Cuba Co-founder and Lead Android Developer of Ke Hay Pa’ Hoy? one of the most prominent startups from Cuba in 2016. The app was a cultural event guide happening in La Habana, Cuba. • Developed Android Mobile Application. Applied innovative solutions in mobile app development for the entertainment and internet services industries in Cuba. • Created an internet business that won multiple entrepreneurship awards like 10x10kCuba Competition and Top 10 Cuban Mobile Apps. • Became one of the primary means of communication for the International Book Fair of Havana in 2016 • Collaborated in a partnership with Netflix for technical support during the celebration of the Netflix QBR event in April 2016 in Havana, Cuba. • Evangelizer of the Cuban entrepreneurial sector at the US Department of the Treasury, US Department of Commerce, and US Department of State. Promoting debate with part of the Cuban Working Group of the Congress of the United States to support the economic engagement between Cuba and the USA. ### Android developer and UI/UX Designer @ AT3W Lightning Protection Jan 2016 – Jan 2016 | Cuba Designed and built an Android app to facilitate the revision process of lightning systems. Reported directly to the Company CEO and CTO about Android Product Development Status. • Independently created, and designed from scratch a mobile application. • Designed a mobile application oriented for tablets using Photoshop. • Designed and implemented solutions for data persistence in the app, to allow workers to use the app in wireless dead zones. ### Automation Engineer @ Integrated Technological Research Complex Jan 2014 – Jan 2016 | La Habana, Cuba ## Education ### Bachelor of Engineering - BE in Automation Engineer Technology/Technician Universidad Tecnológica de La Habana "José Antonio Echeverría"​, CUJAE Jan 2009 – Jan 2014 ### Bachillerato IPVCE V.I. Lenin Jan 2005 – Jan 2008 ## Contact & Social - LinkedIn: https://linkedin.com/in/jalejandrohperez --- Source: https://flows.cv/juanhernandez JSON Resume: https://flows.cv/juanhernandez/resume.json Last updated: 2026-03-22