Xavi Moreno, Software Developer in Tarragona, Spain
Xavi Moreno

Software Developer in Tarragona, Spain

Member since March 7, 2017
Xavi is a qualified, seasoned software developer with several years of commercial experience in the private industry and at the university. Not only has he developed several JavaScript front-end applications for both mobile and web platforms, but he has also built their respective back-ends and APIs in JavaScript, Java, and PHP.
Xavi is now available for hire


  • Skyscanner
    JavaScript, TypeScript, AWS, Docker, Kubernetes, Swift, Kotlin, iOS, Android...
  • Book a Birdie (via Toptal)
    React Redux, JavaScript, PHP, Node.js, React Native, ECMAScript (ES6)...
  • Red Sift
    JavaScript, React, Python, Node.js, TypeScript



Tarragona, Spain



Preferred Environment

GitHub, GitLab, WebStorm, IntelliJ, Unix, PyCharm, TypeScript, PostgreSQL

The most amazing...

...thing I've coded is an offline-first mobile app from scratch.


  • Senior Software Engineer

    2021 - PRESENT
    • Participated in features applied on every platform like desktop, mobile, iOS, and Android.
    • Defined back-end scope with scalability in mind and focused on not wasting users' time, suiting to best experience whilst using Skyscanner.
    • Performed forecasting and organizing tasks, defining limitations, identifying limitations, and facilitating meetings to overcome issues.
    • Analyzed, defined, and migrated services to AWS and custom in-house solutions.
    • Developed complete customer-facing end-to-end features that scale to the entire company's userbase.
    Technologies: JavaScript, TypeScript, AWS, Docker, Kubernetes, Swift, Kotlin, iOS, Android, React, Java, Python, Python 3, Axios, Jira, Git, GitHub, MongoDB, PostgreSQL, Firebase
  • Freelance Senior Software Engineer

    2018 - PRESENT
    Book a Birdie (via Toptal)
    • Drove the entire software development lifecycle including testing, CI/CD pipelines from scratch.
    • Directed both mobile apps in React Native and applied best practices, optimizing the code on the go.
    • Gradually updated the API using a self-made versioning system.
    • Applied monitoring and metrics tooling around the mobile apps to have better analytics regarding the app usages.
    • Mentored, onboarded, and managed new developers as they joined the company.
    Technologies: React Redux, JavaScript, PHP, Node.js, React Native, ECMAScript (ES6), TypeScript, WebSockets, Firebase
  • Senior Software Engineer

    2020 - 2021
    Red Sift
    • Developed part of the core machinery for an email security product.
    • Collaborated with the design team, product managers, and stakeholders to create successful products.
    • Orchestrated tasks into small chunks of work in order to distribute work between team members.
    Technologies: JavaScript, React, Python, Node.js, TypeScript
  • Full-stack Software Engineer

    2012 - 2020
    Hidro Tarraco
    • Developed an offline-first application for the commercial team using React Native for the front end and Java (Spring Boot) for the back end.
    • Created a series of APIs to enhance data usage between several independent applications using Java with JPA/Hibernate for data-access-related actions and JWT to secure the services.
    • Developed a centralized storage-management web application with a search engine to query the products available between different companies.
    • Created the commercial application of the company for iOS and Android platforms using React Native (JavaScript) for the front end and Java (Spring Boot) for the back end.
    Technologies: Spring Boot, React Native, React, Java, JavaScript, WebSockets, Firebase
  • Freelance React Native Consultant

    2018 - 2018
    Leap Forward (via Toptal)
    • Wired FCM push notifications.
    • Provided guidance and helped building the core of the APP.
    • Mentored junior developers who were learning React Native and Javascript.
    • Analyzed and gave tips to improve the Redux store.
    Technologies: JavaScript, React Redux, Firebase Cloud Messaging (FCM), React Native, Firebase
  • Freelance React Native Developer

    2017 - 2018
    Lunabyte, Inc. (via Toptal)
    • Created a React Native application from scratch based on raw requisites; for Android and iOS.
    • Developed the API client together with the back-end engineer.
    • Built an engine displaying new sections on demand.
    Technologies: Android, iPhone, Mobile Apps, React Native, JavaScript
  • Freelance React Native Developer

    2017 - 2018
    TaMedHunden (via Toptal)
    • Created an app from scratch.
    • Based the entire new codebase using multi-repositories with code-sharing so that the core methods could be used by any project's branch.
    • Designed the Redux app's structure.
    Technologies: JavaScript, ECMAScript (ES6), Geolocation, Redux, React Native
  • Software Engineer

    2015 - 2018
    University Rovira i Virgili
    • Wrote a large number of various formulas to query the existent data against some predefined filters using PrimeFaces and Spring for both the front-end and back-end sides.
    • Created a collaborative filtering module with Apache Spark.
    • Developed an information gathering module to transform the obtained data into statistical information using Java.
    • Built the environment and handled the implementation of dockers for some of the software implementations of the university.
    Technologies: PrimeFaces, Spring Boot, Java, WebSockets
  • JavaScript Engineer

    2017 - 2017
    • Created some parts of the public-facing front-end of a commercial web page.
    • Contributed to the build of some graphQL queries.
    • Created internal applications for logged-in users.
    Technologies: Node.js, GraphQL, Apollo, ECMAScript (ES6), JavaScript, Redux, React
  • Freelance React Native Consultant

    2017 - 2017
    Loqus (via Toptal)
    • Created a reusable React Native boilerplate to be used as the base for future projects.
    • Bridged some native components and SDK to be used as React Native packages.
    • Provided a Realm environment for offline-first and encrypted storage system.
    Technologies: Swift, Java, Android, React Native, JavaScript
  • Freelance Full-stack Software Engineer

    2017 - 2017
    ImpartialAI (via Toptal)
    • Built a system that analyzes a given document using AI techniques and finds related documents.
    • Implemented a Socket.IO communication system to submit and retrieve live data.
    • Created a Flask web server to provide both static files and API access.
    • Provided a filtering and parameterization system to tune up the data and get a proper config to set as defaults and provide more reliable data.
    • Created a single web app to interact with the back-end and display the filters and parameters to be configured and show the related documents along with the scores we did use to sort them out.
    • Stored both the analyzed and retrieved information onto a Google spreadsheet for the final user to get a better understanding.
    Technologies: JavaScript, jQuery, Socket.IO, Flask, Python
  • Freelance Senior JavaScript Engineer

    2017 - 2017
    Apoyo al estudio (via Toptal)
    • Created an MVP's front-end for educational institutions to provide a better way to teach the students and to give advice to teachers when planning the course.
    • Built the core of a single-page application using React, Redux, and a React router as the base.
    • Provided a role-based authorization mechanism using JWT and back-end defined roles.
    • Implemented a system that restores the entire store and routing state based on some local-stored keys.
    Technologies: Webpack, Babel, SCSS, Axios, React Router, React Redux, React, JavaScript


  • Book a Birdie

    A beauty-as-a-service platform: it's like Uber for beauty services like haircuts, massages, and more.

    I drove both customers' and professionals' applications and helped giving tech advice to the different stakeholders.

  • Hidro Tarraco Mobile App

    A commercial application for the company that enables users to obtain information about the stores, read, store the information locally in catalogs, and then keep in touch with the company.

  • TaMedHunden App

    I created the TaMedHunden app from scratch with a given back-end. The design originated from a mix of mockups that the project manager and I built. It was built for iOS and Android devices.

  • Gnick Knows App

    I developed an app from scratch that's pending to be published. It consists of a series of business events around the US. I implemented and bridged the Estimote beacons to detect whether or not a user has an event closer to them and if there is one the app sends them a message.


  • Languages

    JavaScript, JavaScript 6, CSS, HTML, Python, Java 8, SQL, CSS3, Java, HTML5, TypeScript, SCSS, Swift, ECMAScript (ES6), PHP, GraphQL, Kotlin, Python 3
  • Frameworks

    Redux, React Native, Flask, JavaServer Pages (JSP)
  • Libraries/APIs

    React, React Redux, Node.js, React Router, Socket.IO, jQuery
  • Tools

    WebStorm, Git, IntelliJ, GitHub, Babel, Firebase Cloud Messaging (FCM), Fastlane, PyCharm, Webpack, Jira
  • Paradigms

    Object-oriented Programming (OOP), Functional Programming
  • Storage

    MySQL, Spring Data JPA, MongoDB, PostgreSQL
  • Other

    Axios, Sagas, Repository Pattern, Geolocation, Mobile Apps, iPhone, Apollo, GitHub Actions, AWS, WebSockets
  • Platforms

    Unix, Android, Docker, Kubernetes, iOS, Firebase


  • Bachelor's Degree in Computer Engineering
    2012 - 2016
    Rovira i Virgili University - Tarragona, Spain
  • Certificate of Higher Education in Software Development
    2010 - 2012
    Vidal i Barraquer Institute - Tarragona, Spain

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