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Zadat Olayinka, Software Developer in Liverpool, United Kingdom
Zadat Olayinka

Software Developer in Liverpool, United Kingdom

Member since August 16, 2022
Zadat is a diligent software engineer with over four years of professional experience building and deploying high-quality solutions for fintech, education, gaming, ticketing, and eCommerce. He has overseen projects from inception to client release and worked on hybrid mobile applications, API/microservices, SDKs/plugins, and web applications. Zadat understands the importance of quality code and excellent communication, which have been the core of his achievements over the years.
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Portfolio

  • DDM Health
    JavaScript, PHP, Laravel, Vue, Redis, MongoDB, Full-stack, REST, APIs, Nuxt.js
  • HackerBay
    JavaScript, Express.js, Ruby, Go, Java, PHP, Python, Neo4j, MongoDB, React...
  • ARM Pensions
    JavaScript, PHP, Laravel, Lumen, Ionic, Cordova, Capacitor, Algorithms...

Experience

Location

Liverpool, United Kingdom

Availability

Part-time

Preferred Environment

MacOS, Linux, Visual Studio Code, Vim Text Editor, Slack

The most amazing...

...project I've built was a hybrid mobile application for managing pensions and investments used by over 100,000 clients to date.

Employment

  • Full-stack Engineer

    2022 - PRESENT
    DDM Health
    • Fixed existing bugs with features currently in production and reduced the request time of API requests by 60%.
    • Integrated the back and front end with Stripe, increasing sales by 25%.
    • Developed a care network management for new users and an integration with Slack, with over 400 users onboarded.
    • Designed a discount and reward system and integrated it with required departments and Stripe for a seamless process.
    Technologies: JavaScript, PHP, Laravel, Vue, Redis, MongoDB, Full-stack, REST, APIs, Nuxt.js

  • Full-stack Engineer

    2020 - 2021
    HackerBay
    • Built an application monitoring system with 10,000+ clients, monitoring server time up, application error logs, error tracking with a stack trace, and root cause analysis.
    • Developed SDKs installable by third-party clients to interact with a server-side API in six languages.
    • Analyzed and classified data using Neo4j and graphical representation with D3.js.
    • Developed an AI email Chrome extension used in predicting email content.
    • Revamped a client's portfolio project using Gatsby.
    • Built a set of reusable website components in standardized styles to allow for reusability.
    • Improved test coverage to 75% for all existing features on microservices.
    • Developed an error tracking and application logging feature on the API and web app.
    • Worked on improving the API documentation to ease clarity for consumption by other developers.
    • Developed GitLab scripts for each microservice to manage the building, testing, and deployment to staging and production on GCP.
    Technologies: JavaScript, Express.js, Ruby, Go, Java, PHP, Python, Neo4j, MongoDB, React, Redux, Mocha, Chai, JUnit, PHPUnit, Data Structures, Algorithms, Node.js, Amazon Web Services (AWS), Google Cloud Platform (GCP), Full-stack, Amazon Cognito, REST, APIs, Contentful, Next.js

  • Full-stack Engineer

    2019 - 2021
    ARM Pensions
    • Developed a hybrid pension and investment management mobile application with 100,000+ users on Android and iOS platforms.
    • Developed a script for processing based64 files to binary files, which increased TAT by about 90% for processing application information on Microsoft Navision.
    • Integrated with Paystack to allow users to buy into different investments and bonds.
    • Built a Toolkit API used by staff to manage clients' data, monitor clients' activity, give insight into how to manage their pension, etc.
    • Developed multiple microservices to integrate with an external payment system for managing payroll.
    • Built a hybrid onboarding application used by sales agents in onboarding new clients to the pension system.
    • Converted mockups into the company website using Vue, Nuxt.js, and Tailwind CSS. Also, I built in new features and managed the web application.
    • Built an embassy request and statement request service.
    • Developed an employer portal used by employers to manage their staff's pension remittance, among others.
    • Developed a geolocator used by clients and staff agents to map the nearest clients trying to open a pension account with the agent in the area.
    Technologies: JavaScript, PHP, Laravel, Lumen, Ionic, Cordova, Capacitor, Algorithms, Express.js, React, Mocha, Chai, PHPUnit, Node.js, SQL, Heroku, Next.js, Vue, Full-stack, REST, APIs, Contentful, Nuxt.js

  • Full-stack Developer

    2019 - 2020
    Touchcore Technologies
    • Built an internal VISA management application for an agency using Laravel and React.
    • Built a diagram ordering system for architectures using Laravel and React.
    • Integrated the existing application with Interswitch third-party APIs to process fee collection smoothly and seamlessly.
    • Developed API microservices for event and ticket management using Lumen.
    • Managed multiple site deployments to cPanel. Troubleshot in production.
    Technologies: PHP, JavaScript, PHPUnit, Mocha, Chai, Full-stack, Tailwind CSS, Laravel, Lumen, CSS, React, cPanel, Web Hosting & Domain Setup, MySQL, Heroku, Apache, REST, APIs

  • Software Engineer

    2018 - 2019
    Shopping Internet Services
    • Developed REST APIs using the TTD approach focused on correctness, authentication, authorization, scalability, and efficiency.
    • Worked in a team that delivered a field agent mobile application for bringing in new clients.
    • Increased test coverage on existing microservices by 40%.
    • Implemented features on the microservices built on the Spring Boot framework.
    Technologies: Java, Hibernate, Angular, Ionic, OAuth 2, Spring Boot, JUnit, JavaScript, Mocha, CircleCI, Amazon Web Services (AWS), Google Cloud Platform (GCP), Heroku, cPanel, REST, APIs

Experience

  • ARM Engage
    https://play.google.com/store/apps/details?id=com.arm.engage

    ARM Engage is an Android and iOS application used for both investing and managing pensions. I built the UI from wireframes delivered to me and also built the APIs being used by the mobile application. I integrated the app with Firebase to manage crash analytics, push notifications, etc. It has over 100k users as of now and has a very impressive rating on both the Android and iOS stores.

  • Granula

    Granula is a custom survey system where users can create custom questions with custom options, and users can also answer these surveys for a particular incentive.

    FEATURES
    • Users can create custom surveys.
    • Users can create custom questions and options for each question.
    • Users pay a particular fee to have access to the system.
    • Respondents are vetted to be on the system.
    • They are invited to respond to surveys that fit them.
    • Respondent gets incentives in terms of airtime and cash for these surveys.
    • Users get quality data that can be exported for further analysis.

  • WhotApp

    WhotApp gives users the access to bet on the Whot playing card while they compete against one another

    FEATURES:
    • Users can create an account with their social OAuth.
    • Users can fund their accounts using paystack.
    • Users can send invites to any other user to compete.
    • Users play against each other in real time.
    • Winner takes it all.

  • Ticketing App
    https://api.ticketpro.tcore.xyz/

    A ticket management API used for creating and managing events, guests and invitations, and payment collection and refunds.

    FEATURES
    • Users are able to create accounts and create events.
    • Different subscriptions decide what features users have access to.
    • Events can be customized to users' perfection.
    • Invitations can be sent out to the public.
    • Tickets can be purchased and sales managed on behalf of the event organizer.
    • Organizers have access to both funds and guests.

  • ChipTranz

    ChipTranz is a mobile application used by users to save money, it provides a seamless interaction, and it has processed over 5 million nairas over time. I integrated with an existing API for this project

    FEATURES
    • Users have access to creating saving plans.
    • Users can integrate with payment systems like Paystack for reoccurring savings.
    • Users can manage their savings.
    • Users can make a withdrawal.
    • Push notifications are also managed for users.

Skills

  • Languages

    JavaScript, PHP, Java, TypeScript, Ruby, Go, Python, CSS, SQL, HTML, ECMAScript (ES6), HTML5

  • Frameworks

    Express.js, Redux, JUnit, PHPUnit, Laravel, Lumen, Ionic, Tailwind CSS, Angular, OAuth 2, Next.js, Spring, Hadoop, Swagger, Hibernate, Spring Boot, Nuxt.js

  • Libraries/APIs

    React, Chai, Node.js, Vue, Stripe API

  • Tools

    Mocha, Vim Text Editor, Slack, CircleCI, Apache, Firebase Analytics, Amazon Cognito

  • Paradigms

    REST, Agile Software Development, API Architecture

  • Platforms

    MacOS, Linux, Contentful, Apache Pig, Visual Studio Code, Amazon Web Services (AWS), Google Cloud Platform (GCP), Heroku, cPanel, Firebase, Docker

  • Other

    Full-stack, APIs, Back-end, Back-end Development, Data Structures, Algorithms, Cordova, Capacitor, Software Design, System Design, Architecture, Machine Learning, Metaheuristics, Big Data, Web Hosting & Domain Setup, Hybrid Apps, ES6 Promises, Push Notifications

  • Storage

    MongoDB, Redis, Neo4j, MySQL

Education

  • Master's Degree in Computer Science
    2021 - 2022
    Liverpool Hope University - Liverpool, England
  • Bachelor's Degree in Computer Science
    2014 - 2018
    University of Ibadan - Ibadan, Nigeria

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