Alonso Ayala Ortega, Developer in Málaga, Spain
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Alonso Ayala Ortega

Verified Expert  in Engineering

Full-stack Developer

Málaga, Spain
Toptal Member Since
September 18, 2017

Alonso is a professional software engineer with over 10 years of experience creating highly maintainable software products. He's a seasoned full-stack developer with test automation experience. Thanks to excellent communication skills and a keen eye for specification analysis, Alonso delivers bug-free solutions that 100% meet the client's requirements.


WhereTo, Inc.
Web Services, ECMAScript (ES6), Docker, PostgreSQL, React, Node.js
Java, Spinnaker, Amazon Web Services (AWS), PostgreSQL, Microservices, gRPC
Osprey Underwriters
Docker, MongoDB, React, Node.js




Preferred Environment

Continuous Integration (CI), Behavior-driven Development (BDD), Docker

The most amazing...

...project I've created is a market engine that integrates multiple technologies, including a framework that runs E2E acceptance tests.

Work Experience

Software Engineer

2018 - PRESENT
WhereTo, Inc.
  • Created an E2E testing framework using behavior-driven development.
  • Built a tool to upload multiple users using Node.js streams and functional programming.
  • Developed a vehicle booking module using RESTful services.
  • Led in improving quality by introducing BDD tests and TDD techniques.
  • Built a vehicle searching module by evaluating and parsing XML responses from Travelport.
  • Created a man-in-the-middle tool to mock responses from third-party web services to run stress tests.
  • Improved the traveling tool's seat selection process.
  • Fixed complicated bugs utilizing Node.js and PostgreSQL.
  • Built a tool using React and Mapbox to visualize a nondeterministic functionality of airport geo-location searching that helped reduce availability errors by 68%.
  • Added functionality to modify hotel reservations which reduced the number of support calls by 76%.
Technologies: Web Services, ECMAScript (ES6), Docker, PostgreSQL, React, Node.js

Senior Software Engineer

2021 - 2021
  • Managed multiple microservices using gRPC and proto3.
  • Implemented new features and fixed bugs using Java 8 and Spinnaker.
  • Ramped up quickly in my first week to implement new features.
Technologies: Java, Spinnaker, Amazon Web Services (AWS), PostgreSQL, Microservices, gRPC

Full-stack Software Engineer

2019 - 2021
Osprey Underwriters
  • Created a continuous deployment workflow using Docker, Heroku, and Nginx.
  • Developed an automated framework for E2E testing that ensured that everything kept working well after changes and code refactorings.
  • Created the system's admin portal using React and implementing multi-factor authentication.
  • Converted the starting Node/React project into a production-ready solution using Docker, Heroku, and AWS.
  • Maintained code for the insurance solution using Node, React, and MongoDB.
  • Created a scheduled task for exporting information using Node.js.
  • Dockerized the application services to get a better code development experience.
  • Created responsive home web pages for insurance products using modern CSS.
  • Created an elastic IP proxy with AWS/Nginx to overcome Heroku’s dynamic IP issue.
Technologies: Docker, MongoDB, React, Node.js

Software Engineer

2018 - 2018
Sonar Trading
  • Created a module to connect to a currency trading exchange using concurrent algorithms.
  • Created and improved integration tests, which helped us verify the quality of the application.
Technologies: JUnit, LMAX-Exchange Disruptor, Java 8

Software Engineer

2016 - 2018
Sabre Airline Solutions
  • Created automated acceptance tests using a homegrown API client framework, AssertJ, and Hamcrest.
  • Created a Cucumber/BDD project that helped business analysts create auto-verifiable specifications.
  • Helped the QA team finish their testing plan for some of the released versions of the system.
  • Delivered 100% bug-free solutions for a REST API module that consumes data from internal and external web services and produces information in JSON format aimed at our React web app.
  • Developed full-stack flight reservation solutions.
Technologies: Redux, React, Mockito, JUnit, Spring, Java, RESTful Services, Back-end

Software Engineer

2014 - 2016
  • Supported RESTful web service modules that provided travel solutions for multiple airlines and travel agents around the world.
  • Created automation tests using Selenium WebDriver and improved the automation framework using the page object model.
  • Ensured the quality of SQL migration scripts by making optimizations that made no-downtime system upgrades possible.
  • Applied SOLID principles and XP practices like test-driven development, code reviews, and pair programming in order to create clean code features.
  • Developed front-end solutions using JavaScript, Ember.js, and Handlebars.
  • Supported a connectors module which gathered information from multiple external global distribution systems (GDS).
  • Created optimized SQL scripts to run data migrations using Psql and pgAdmin 3.
Technologies: PostgreSQL, Web Services, JavaScript, Git, Apache Maven, EasyMock, JUnit, Spring, Java, RESTful Services, Selenium WebDriver

Software Engineer

2013 - 2014
  • Troubleshot tricky defects found in Oracle ADF and Oracle JDBC frameworks.
  • Helped the QA team run functional tests using Oracle Application Testing Suite (OATS).
  • Supported a tax collection system using Oracle ADF BC, ADF Faces, and Java Swing.
  • Solved critical bugs in Java and PL/SQL code using JDeveloper and SQL Developer.
  • Verified Java and PL/SQL code and Oracle database schemas to apply possible optimizations.
  • Made several performance improvements to stored procedures applying optimizations to PL/SQL code and Oracle database tables.
Technologies: PL/SQL, Oracle ADF, Oracle, Oracle Database, Java

Software Developer

2010 - 2013
Union de Credito Progreso S.A. de C.V.
  • Created a mobile banking Android app that consumed web services from the core banking module.
  • Made optimizations to T-SQL cursors that reduced its processing time up to 70%.
  • Created T-SQL scripts to automate account charges using SQL Server scheduled tasks.
  • Supported an online banking application developed in ASP.NET and SQL Server 2005.
  • Implemented multi-factor user authentication to our web banking application using RSA SecurID hardware tokens.
Technologies: Microsoft SQL Server, .NET, Android

SCyA - KanBan and BTO Manufacturing System

SCyA (Connectivity and Administration System) is a modular solution that allows manufacturing plants to connect their processes in a simple way, combining the KanBan methodology with BTO, which allows only the correct replacement of what is consumed.

And in the administration part, it allows you to monitor the production and traceability of your product in real-time, as well as downtime tracking.

Minisuper is a disruptive technology solution focused on making efficient purchases of basic foods like tortillas, fruits, canned goods, soft drinks, etc.

With our mobile app, consumers order a product whose order is assigned to the best ranking deliverer based on their proximity, reputation, and offered price.

Minisuper charges an access fee to deliverers, which is calculated based on their weekly sales.

ES6 | React | React Native | Koa | Knex | Docker | Socket.IO | Cucumber BDD.

BBO and Trading Simulator
BBO app (Best Bid and Offer) that connects to an exchange provider using its REST API and web socket endpoints.

It retrieves BTC trades and current orders in real time showing the best bids and best asks in the UI.

It also simulates trade orders based on a "contrarian" algorithm which creates trades based on BTC price downticks and upticks.

Java FX8 | Concurrent programming | WebSockets | REST API
2018 - 2020

Master's Degree in Applied Computer Science

University of West Georgia - Carrollton, GA

2006 - 2010

Bachelor of Science Degree in Computer Engineering

Instituto Tecnologico de Delicias - Chihuahua, Mexico


AWS Certified Developer Associate

Amazon Web Services


Node.js, React, Socket.IO, Selenium WebDriver, EasyMock, LMAX-Exchange Disruptor, Protobuf


Cucumber, Git, IntelliJ IDEA, Mocha, Apache Maven, Docker Compose, Gradle, Amazon Elastic Container Registry (ECR), Amazon Elastic Container Service (Amazon ECS), Knex.js


JUnit, Redux, Mockito, Spring, Spring Security, Jest, Next.js, .NET, Oracle ADF, AWS Serverless Application Model (AWS SAM), gRPC


HTML, CSS, ECMAScript (ES6), Java, JavaScript, SQL, HTML5, TypeScript, Java 8, Python, Ruby, Java 9


Functional Programming, Test-driven Development (TDD), Behavior-driven Development (BDD), Microservices Architecture, Continuous Integration (CI), Microservices


JSON, Redis, MySQL, PostGIS, PostgreSQL, Oracle PL/SQL, MongoDB, Microsoft SQL Server, PL/SQL, Amazon DynamoDB, Amazon S3 (AWS S3)


Linux, Oracle Database, Oracle, Docker, AWS Lambda, AWS Elastic Beanstalk, Android, Amazon Web Services (AWS), Spinnaker


Web Services, QA Automation, RESTful Web Services, APIs, MERN Stack, Back-end, Spring Cloud, Front-end, RESTful Services, Amazon API Gateway

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