Christopher is available for hire

Christopher Brown

Verified Expert in Engineering

Back-end Developer

London, United Kingdom

Toptal member since December 27, 2021

Expertise

Back-end Developers Java Spring Boot Dashboard AWS Git Linux SQL Spring Apache Kafka MySQL REST API Kotlin Selenium Web Scraping

Bio

Christopher is a highly skilled back-end software engineer with more than eight years of expertise in Kotlin and Java. He specializes in developing robust, scalable applications and APIs and has a proven track record across diverse industries, including telecom, banking, commodities, crypto, and gaming. Driven by a passion for creating reliable, high-performance systems, Christopher is committed to advancing innovation and achieving business success.

Portfolio

10x Banking

Kotlin, Amazon S3 (AWS S3), Amazon Athena, Apache Kafka, Kafka Connect...

Vonage

Java, Apache Kafka, Filebeat, Python, Docker, Nomad, MySQL, Architecture...

Blockchain.com

Kotlin, Java, Nomad, PostgreSQL, Docker, Protobuf, Apache Kafka, Cryptocurrency...

Experience

Software Engineering - 5 years
Java - 5 years
Amazon Web Services (AWS) - 5 years
Linux - 4 years
Cryptocurrency - 3 years
Apache Kafka - 3 years
Python - 2 years
Kotlin - 2 years

Availability

Full-time

Preferred Environment

IntelliJ IDEA, MacOS, Linux, Java, Kotlin

The most amazing...

...feature I've implemented was a cryptocurrency airdrop gifting over $15 million worth of tokens to 300,000 people worldwide, subject to KYC criteria.

Work Experience

Software Engineer

2022 - 2023

10x Banking

Developed an SQL query API data lake access gateway, facilitating interface compatibility with Amazon Athena, Apache Pinot, and Aurora using Kotlin, which streamlined data queries and improved accessibility for analytics and reporting.
Created a bulk operations application employing reactive Java with Spring Boot, enhancing the efficiency and scalability of data processing tasks within the organization.
Made significant contributions to the data lake infrastructure, including integrations with Kafka Connect, Amazon S3, Amazon Athena, Apache Airflow, and Aurora, strengthening the organization's data processing and management capabilities.
Focused heavily on PostgreSQL performance optimization, implementing strategies that significantly improved database efficiency and query speeds, enhancing overall system performance.

Technologies: Kotlin, Amazon S3 (AWS S3), Amazon Athena, Apache Kafka, Kafka Connect, Amazon Web Services (AWS), Terraform

Java Engineer

2020 - 2021

Vonage

Designed and delivered multiple product features using Kotlin, working directly with telecom providers. I have been a key contributor in aggregating next-generation 5G APIs.
Automated Gradle Catalogue upgrade for dependencies.
Implemented a shared cache and callback scheduling service with Hazel cast.

Technologies: Java, Apache Kafka, Filebeat, Python, Docker, Nomad, MySQL, Architecture, Microservices, Spring Boot, REST APIs, Jenkins, Software Development, Spring, Git, SQL, Back-end, Dashboards, API Integration, Automated Testing, REST Assured, Selenium, Kotlin, Kubernetes, Amazon Web Services (AWS), Terraform

Platform Engineer

2019 - 2020

Blockchain.com

Contributed to a leading consumer crypto platform, specializing in crypto exchange services, by inheriting and enhancing the Mercury events service, achieving one hundred times improvement in read and write performance.
Utilized a robust tech stack including PostgreSQL, Kafka, Kotlin, and Java to deliver high-performance features end-to-end, crossing over into other services such as real-time candles, airdrop center, and order history CSV.
Delivered the Block Stack airdrop, distributing $70 million worth of crypto tokens to verified customers, showcasing an exceptional ability to execute large-scale financial transactions securely and efficiently.
Increased the write and read performance of the crypto exchange event service by over one hundred times, significantly improving the system's efficiency and user satisfaction by enabling faster transaction processing.
Implemented an order history feature in CSV format for the crypto exchange, providing users with a comprehensive and downloadable transaction history, enhancing transparency and trust in the platform.
Executed a massive crypto airdrop, successfully registering 300,000 individuals to receive verified cryptocurrency directly into their wallets, demonstrating effective project management and execution capabilities.
Added real-time candlestick charts to the crypto exchange's price charts, improving the trading experience by providing users with dynamic and detailed market analysis tools.

Technologies: Kotlin, Java, Nomad, PostgreSQL, Docker, Protobuf, Apache Kafka, Cryptocurrency, Amazon Web Services (AWS), IntelliJ IDEA, Linux, Microservices Architecture, REST APIs, Software Development, Git, Back-end, Dashboards, API Integration, Terraform

Software Engineer

2018 - 2019

Bosonic (formerly OTCXN)

Contributed significantly to the development of OTC and exchange trading platforms, utilizing TIBCO, FIXML, and Java to enhance trading efficiency and reliability.
Developed and maintained an automated test suite, enabling concurrent test runs across multiple FIX gateway sessions to ensure platform integrity and performance.
Innovated a "Robo-trader" solution to automate order placement in test environments, providing realistic trading conditions for testing and client demonstrations.
Designed a multithreaded integration test framework that supports WebSocket, FIX connections, and REST interfaces, streamlining the testing process for various trading platform functionalities.
Implemented a liquidity provision strategy through the Robo-trader, improving the representation of market conditions in our test environments and enhancing the demonstration experience for potential clients.
Played a pivotal role in team expansion and talent acquisition, interviewing and onboarding new engineers as the second hire in the Belfast office, contributing to the team's growth and development.

Technologies: Java, Apache Kafka, TIBCO, Software Development, Spring, Git, MySQL, Back-end, Dashboards, Selenium, API Integration, Web Scraping, Amazon Web Services (AWS)

Junior Software Engineer

2017 - 2019

CME Group

Designed and maintained comprehensive automated test suites, utilizing tools such as SOAP UI, REST Assured with behavior-driven development (BDD), and Selenium with BDD to test web services and graphical user interfaces thoroughly.
Developed a sophisticated Selenium WebDriver automation suite in Java, specifically for GUI integration tests, facilitating effective user interaction testing, including clicking and dragging components.
Created a REST Assured integration test suite for REST endpoints in Java, ensuring the robustness and reliability of web service interactions within the STP application.
Built a FIXML integration test suite using Cucumber and Java, enhancing the application's compatibility and integration capabilities with financial information exchange protocols.
Innovated in GUI testing by employing Selenium and BDD methodologies to automate complex user interaction scenarios, significantly reducing manual testing efforts and improving test accuracy.

Technologies: Java, Software Development, Spring, Git, MySQL, Back-end, Selenium

Experience

Telegram Price Alert Bot

https://t.me/pX_page_bot

I'm building a Kotlin application that gathers prices from different sources and aggregates them to my Reference price. I have exposed a Telegram bot using Kotlin to allow users to configure and receive price alerts.

Education

2014 - 2018

Bachelor's Degree in Computer Science

Queen's University Belfast - Belfast, Northern Ireland, UK

Skills

Libraries/APIs

REST APIs, ReactiveX, Protobuf

Tools

IntelliJ IDEA, Git, Jenkins, REST Assured, Amazon Athena, Kafka Connect, Terraform

Languages

Java, Kotlin, Java 8, SQL, Python, C#, C++

Frameworks

Spring Boot, Spring, Selenium, Unity

Platforms

Linux, Apache Kafka, Amazon Web Services (AWS), MacOS, Docker, Android, Kubernetes

Storage

MySQL, PostgreSQL, Amazon S3 (AWS S3)

Paradigms

Microservices Architecture, Microservices, Unit Testing, Automated Testing

Other

Back-end, Software Engineering, Cryptocurrency, API Integration, Dashboards, Filebeat, TIBCO, Nomad, Architecture, Software Development, Trading, Web Scraping, Telegram Bots, Bots, APIs, Crypto

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