Mikel Pascual, Developer in Bristol, United Kingdom
Mikel is available for hire
Hire Mikel

Mikel Pascual

Verified Expert  in Engineering

Software Developer

Bristol, United Kingdom
Toptal Member Since
March 28, 2017

Mikel has over a decade and a half of experience in software development. As a highly skilled full-stack developer, he has worked with multiple startup and high profile companies like Amper, Indra, and Dyson. Being well-versed in a variety of languages—he has over a decade of experience in Java and PHP and over five years of experience with Android—makes him a highly valuable addition to both web-based and mobile-first projects.


Vilua Healthcare
Android, Amazon Web Services (AWS), Go, Flutter, Bamboo, Jira, Microsoft Teams...
Instana, Inc.
Android, Flutter, React Native, Bytecode, iOS, Xcode, Kotlin...
Divvy Engagement
Amazon Web Services (AWS), MySQL, Go, JavaScript, Bitbucket...




Preferred Environment

LAMP, Git, Android Studio, IntelliJ IDEA, Linux, Go

The most amazing...

...thing I've coded is an encrypted video, audio, and messaging communications system—5x more efficient than the unencrypted industry standard.

Work Experience


2021 - 2023
Vilua Healthcare
  • Created a new SDK for health assessment and recommendations.
  • Assisted the existing software development lifecycle and DevOps operation, achieving a significant reduction in maintenance costs and an increase in development agility.
  • Assisted with the creation of a long-term vision for the technical side of the future of the company, leading to a merger and international expansion.
Technologies: Android, Amazon Web Services (AWS), Go, Flutter, Bamboo, Jira, Microsoft Teams, Kotlin, Mobile Development, Native Mobile Apps

Senior Software Engineer

2020 - 2022
Instana, Inc.
  • Built an entire Android monitoring agent with bytecode manipulation, HTTP monitoring, and performance monitoring.
  • Developed a React Native monitoring agent for HTTP monitoring and performance monitoring through the use of a wrapper.
  • Built a Flutter monitoring agent for HTTP monitoring and performance monitoring through the use of a wrapper.
  • Provided technical support for clients during implementation and maintenance stages.
  • Assisted in the knowledge process after the company was acquired and integrated into IBM.
Technologies: Android, Flutter, React Native, Bytecode, iOS, Xcode, Kotlin, Mobile Development, Native Mobile Apps

DevOps Engineer

2019 - 2022
Divvy Engagement
  • Created API integrations with third-party providers with both ColdFusion and Go.
  • Developed multiple public APIs and standalone services.
  • Created and managed an AWS infrastructure for the company.
  • Set up and maintained the CI structure for all components of the system.
  • Migrated a legacy ColdFusion codebase to a new Go- and Vue-based platform.
Technologies: Amazon Web Services (AWS), MySQL, Go, JavaScript, Bitbucket, Microsoft SQL Server, Adobe ColdFusion, Native Mobile Apps

Senior Software Engineer

2019 - 2020
TTP - The Technology Partnership
  • Created an Android app for a drug-delivery system from the ground up.
  • Implemented Bluetooth Low Energy (BLE) integration.
  • Created animations using Lottie, property animations, transitions, and so on.
  • Set up and managed the CI and distribution system.
  • Worked hand-in-hand leading other developers and planning with PMs, POs, and designers.
Technologies: Android, Kotlin, Mobile Development, Native Mobile Apps

Senior Software Engineer

2018 - 2019
Good Energy
  • Collaborated with other developers to rebuild an Android app.
  • Created multiple animations.
  • Took part in daily standups and weekly reviews.
Technologies: Android, Google Play Store, Kotlin, Mobile Development, Native Mobile Apps

Senior Software Engineer

2018 - 2019
  • Mantained and extended two Xamarin apps.
  • Created two native Android apps from the ground up.
  • Created animations using vector drawables, Lottie, property animations, and video surfaces.
  • Managed the CI systems for Android.
  • Implemented video-streaming clients for DRM-protected video streams.
Technologies: Xamarin, Android, iOS, Google Play Store, Xcode, Kotlin, Mobile Development, Native Mobile Apps

Senior Software Engineer

2017 - 2018
  • Solved existing bugs to increase the app's stability from slightly over 80% to over 99'9%.
  • Created an error-reporting system to keep the app's stability under control.
  • Installed an issue-reporting system to enable the user to generate image-assisted reports.
  • Built-up a chat system for over a million daily users.
  • Implemented all-around fixes to achieve the Editor's Choice award in December 2017.
  • Implemented and maintained Realm database, including migrations.
Technologies: Kotlin, RxJava, Android, Google Play Store, Mobile Development, Native Mobile Apps

Full-stack Developer

2017 - 2018
  • Set up a CI system based on Jenkins.
  • Migrated the following: a website to a private server running LAMP and LEMP and a pure PHP back end to Lumen/Laravel.
  • Created a REST API around an existing database.
  • Improved the performance of an existing MySQL database.
Technologies: MySQL, Go, REST, PHP, Laravel, DigitalOcean, Linux

Senior Android Developer

2016 - 2018
  • Rewrote the platform's Android app.
  • Implemented Dwolla and PayPal payment gateways.
  • Integrated health-tracking platforms like GoogleFit, Fitbit and Validic.
  • Added Amazon Cognito authentication.
  • Implemented the Amazon Gateway mobile SDK.
  • Integrated the Amazon SNS notification system.
  • Fixed bugs and maintained an iOS app.
Technologies: RxJava, Android, iOS, Google Play Store, Xcode, Mobile Development, Native Mobile Apps

Senior Software Engineer

2016 - 2017
  • Performed maintenance and stability tasks on an existing Android app.
  • Created a new Android app with a cross-platform core developed in C++.
  • Built up a CD system based on Stash and Bamboo.
  • Implemented a continuous code-quality tracking system for Android (Java) and iOS (Objective-C and Swift) based on SonarQube.
  • Integrated IoT systems.
  • Debugged network and protocol issues of hardware devices.
  • Designed architecture new mobile apps to support a multisite development structure of tens of developers.
  • Created the architecture design of a multiplatform continuous translation infrastructure for mobile systems.
Technologies: SonarQube, Bamboo, Java, Android, Google Play Store, Mobile Development, Native Mobile Apps

Senior Software Developer

2015 - 2016
EveryLife Technologies
  • Added multiple custom UI elements to an existing Android app.
  • Performed maintenance and stability tasks on existing Android and iOS apps.
  • Created a new cross-platform app using Xamarin and MVVM.
Technologies: Xamarin, iOS, Android, Java, Google Play Store, Xcode, Mobile Development, Native Mobile Apps

Senior Software Engineer

2012 - 2015
  • Created a database system, Android app, and iOS app for a cross-platform encrypted video and audio communication system.
  • Designed and implemented the full-stack of a cross-platform messaging system.
  • Installed an Android-based remote health-monitoring system prototype for British Telecom.
  • Set up a CI system based on Jenkins for Android and iOS.
  • Implemented mobile and web payment systems.
Technologies: PostgreSQL, SQLite, XMPP, JNI, C++, LDAP, iOS, Android, Java, Google Play Store, Xcode, Mobile Development, Native Mobile Apps

Contract Software Engineer

2009 - 2009
  • Implemented a fine-management system for an undisclosable (NDA-bound) police department.
Technologies: Apache, Oracle Database, Java

Software Engineer

2006 - 2008
  • Worked as a system administrator in Windows and Linux environments (active directory, license servers, mail servers, backup servers, networks, and more).
  • Managed the entirety of multiple customized development workflows for CAD software systems such as AutoCAD and M10.
  • Acted in the capacity of a software consultant specializing in Autodesk products.
  • Worked as an AutoCAD electrical instructor.
Technologies: MySQL, Microsoft SQL Server, Java, AutoLISP, Windows, Linux

Software Developer

2002 - 2005
Freelance Work
  • Developed a web application for the management of students' grades for a music school.
  • Built a CMR for a nonprofit organization.
  • Created an ERP for an electrical-component distribution company.
  • Set up a multiple network environment for multiple local small-and-medium-size companies.
  • Developed multiple web pages for small-and-medium-sized companies.
Technologies: Microsoft SQL Server, Oracle Database, MySQL, PHP, CSS, HTML, Google Play Store


With more than 15 million downloads in the Play Store, Cookpad is the world's biggest recipe-sharing community.

The Android version stays at the forefront of state-of-the-art apps, using all the latest technologies and frameworks. It was chosen as the Play Store's Editor's Choice in December 2017, Cafe Bazaar's Best New App in February 2018, among others.

WarnerBros WBTVD

DRM-protected video streaming app built from the ground up, using Kotlin, ExoPlayer, Retrofit, Lottie, and other technologies.

This app is used by WarnerBros as an internal video distribution system as well as to promote their shows during the "show-selling" season.

Enigmedia Secure Communications

A cross-platform system for encrypted video, audio, and text communications.

I had the chance to develop the Android and iOS apps for the system as well as the full-stack development of the messaging system and various parts of the core back end.

Dyson Link

Dyson Link allows the owners of various Dyson products to obtain additional capabilities through the extended report and control facilities offered by the app.

I greatly improved the critical areas of the app's Android version such as the initial setup of the Dyson products so that they can work while connected to the internet.

Feedback on the app drastically improved after my work on it, giving me the subsequent opportunity to design and implement the next generation of the app (to be released later in 2017).

Reached over 200,000 Android users.

WarnerBros FYC

DRM-protected video streaming app built from the ground up, using Kotlin, ExoPlayer, Retrofit, Lottie, dynamic layout rendering, and other technologies.

Used by WarnerBros for digital distribution of screeners.


This is a reactive application using Amazon Cognito and a multitude of AWS services, RxJava, and animation frameworks. It allows users to query multiple food databases, manage their daily activities, monitor their steps, connect a Fitbit device, link their PayPal and Dwolla accounts, and more.


openPASS is a cross-platform app built using Xamarin. Connected to a comprehensive health-care related information database, it allows a family member to be up-to-date with the latest information about their loved ones.

I had the great opportunity to develop the core and Android-specific parts of the system as well as closely working with the head designer to achieve the best possible UX for our users.

Good Energy

This app helps customers understand what types of energy were used to fulfill their needs, get notifications about their coming statements, handle payments, understand their energy bill, learn about other Good Energy products, and more.
2015 - 2017

Master of Science Degree in Information Technologies

University of Liverpool - Liverpool, UK

1999 - 2006

Bachelor's Degree in Telecommunications Engineering

Escuela Técnica Superior de Ingeniería de Bilbao - Bilbao, Spain


Google Cloud Certified Associate Cloud Engineer



RxJava 2, RxJava, NDK


PhpStorm, SonarQube, Android Studio, Bamboo, Stash, Git, Calabash, IntelliJ IDEA, Xcode, Apache, Bitbucket, Subversion (SVN), Jenkins, Adobe Photoshop, Adobe ColdFusion, Jira, Microsoft Teams


Kotlin, Java, SQL, Go, AutoLISP, Swift, HTML, CSS, JavaScript, C#, PHP, C++, Bash, Bytecode


Mobile Development, Model View ViewModel (MVVM), Model View Presenter (MVP), REST, Behavior-driven Development (BDD), Scrum, Agile, Test-driven Development (TDD)


Firebase, Android, Amazon Web Services (AWS), Xamarin, Linux, LAMP, Oracle Database, Windows, DigitalOcean, iOS


SQLite, JSON, MariaDB, MySQL, Google Cloud, Realm, Microsoft SQL Server, MongoDB, PostgreSQL


Dagger 2, Laravel, JUnit, JNI, Espresso, Symfony, Flutter, React Native


Google Play Store, Native Mobile Apps, Internet of Things (IoT), Coroutines, LDAP, XMPP, Video Streaming, Videos, EventBus, SOAP

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.


Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring