Doug Sparling
Verified Expert in Engineering
Platform Developer
Montreal, QC, Canada
Toptal member since January 26, 2015
Doug is driven by a need to improve himself, his colleagues, and the products they build. He has experience with many web, back-end, and mobile platforms, most prominently those that are Java-based, such as JVM or Android. Doug's comfortable working at multiple levels at once, from twiddling bits on the wire or providing technical guidance to teams and C-suites alike.
Portfolio
Experience
Availability
Preferred Environment
Linux, Git, Sublime Text, Android Studio, IntelliJ IDEA
The most amazing...
...service I've created is a stateful, real-time, highly-available distributed system deployed to Kubernetes, handling 20+ thousand simultaneous user connections.
Work Experience
Technical Lead for Android, Back End, and DevOps
OnyxCorp
- Joined as the sole developer, reporting directly to the CTO and inheriting a suite of secure communication and productivity apps that were in rough shape. Prepared server and client apps for production readiness and successfully launched that year.
- Implemented TCP socket servers with Golang for custom binary messaging protocols, tuned for high-latency, low-bandwidth networks. These servers maintain complex client state and scale horizontally to support tens of thousands of concurrent users.
- Containerized Golang and Node.js services and migrated to a distributed data storage to maintain high availability, and for ease of scaling, deployment, and monitoring.
- Implemented DevOps practices across Golang projects to run integration tests, build docker images, and publish automatically to Kubernetes via Argo CD.
- Implemented encryption for mobile data at rest and in motion using secure local storage for Android, and end-to-end encryption with forwarding secrecy across multiple products, including key management, APIs, and protocols.
- Created a Dropwizard-based SMTP gateway to seamlessly encrypt and decrypt PGP email for inter-operation with external email clients.
- Implemented a C++ Envoy plugin for L4 sticky load balancing based on the content of custom protocol messages.
- Helped design and patent a system of key splitting that developed into a major product feature. Implemented the client and server for this system and documented it for inclusion in future products.
- Published internal specs, blog articles, and hosted webinars to coordinate implementation efforts across teams and disseminate knowledge.
Consultant
Cyberdeck Consulting Corp (Self-employed)
- Served as a ghostwriter to small companies and provided content to help drive traffic to their site via SEO.
- Developed small proof-of-concept prototypes for clients, including telephony integration, content management, and geofenced advertising.
- Subcontracted for a research agency to develop interactive reports for their clients.
Consultant
Manitoba Telecom Services (via Protegra)
- Built an Android app for a local telecom to show customers their data usage, bills, and notifications, to enable bill payments, and more.
- Implemented several asynchronous REST calls using Retrofit, including multi-level caching of results, an offline mode, and sophisticated error handling.
- Used Node.js to mock client web services for testing purposes.
- Wrote a detailed developers guide for hand-off to the application maintenance team.
- Executed and wrote test cases for a variety of Android phones and coordinated fixes with QA.
Consultant
Manitoba Blue Cross (via Protegra)
- Mentored many new staff on the effective use of Hibernate, Spring, and Java.
- Designed and implemented rich JavaScript-driven interfaces with the help of analysts for editing and viewing complex insurance information.
- Helped design and develop a JSON REST web service to provide data from an ODS.
- Built batch processes to perform billing, exporting to legacy systems, and letter printing.
- Aided in the creation and extension of common utility libraries for internal use by dozens of projects and developers.
- Created and delivered presentations on functional programming, best practices, design patterns, and test-driven development.
Programmer, Analyst
Winnipeg Transit
- Added new features to a Swing application to allow transit controllers to monitor real-time locations of GPS-enabled buses, create and view incident reports, and communicate with bus operators.
- Designed, implemented, and supported an Oracle-based ODS containing transit service information, supplemented by an in-memory store of real-time data.
- Architected and helped with the implementation of a Rails-based website redesign to deliver real-time service information to customers.
- Helped create an integration REST web service using Java and Cocoon. Developed a Ruby gem for consuming the service from internal Rails apps.
- Introduced continuous integration with Jenkins, artifact management with Nexus, simplified building and deployment with Maven, and version control with Git.
- Pushed for the introduction of Ruby on Rails to the organization and succeeded. Trained existing Java developers for the transition.
Experience
Winnipeg Transit Website
https://winnipegtransit.comMTS MyAccount Android App
https://play.google.com/store/apps/details?id=ca.mts.myaccount&hl=enXTAMTMPL Open-source Project
https://github.com/OnyxCorpInt/xtamtmplEducation
Bachelor's Degree in Computer Science, Philosophy
University of Manitoba - Winnipeg, Canada
Skills
Libraries/APIs
RxJava, Node.js, Q Promises, Apache Lucene, Retrofit, jQuery, REST APIs, React, Cocoon, Underscore.js, JMS, Reactive Extensions
Tools
Subversion (SVN), Git, IntelliJ IDEA, Sublime Text, RxAndroid, Bamboo, Mocha, Jenkins, Apache Maven, Gradle, Android Studio, Android Jetpack, GIS, Jira, Ansible, Gulp, Apache Ant, Jetty, Apache
Languages
C#, Go, Java, Ruby, Kotlin, JavaScript, CoffeeScript, HTML, SQL, Haml, CSS, Scala, SCSS, PHP
Frameworks
Android SDK, Hibernate, Dropwizard, Rx, Dagger, Ruby on Rails (RoR), Express.js, Spring MVC, Jakarta Server Pages (JSP), Apache Struts, Spring, gRPC, Swing
Paradigms
Testing, Unit Testing, Test-driven Development (TDD), Concurrent Programming, DevOps, Continuous Delivery (CD), Socket Programming, Continuous Integration (CI), Functional Programming, Agile Software Development, REST, Database Design, RESTful Development
Platforms
Jakarta EE, Kubernetes, Linux, Android, Docker, WordPress, Oracle, Heroku, Windows
Storage
FoundationDB, MySQL, PostgreSQL
Other
Protocol Design, Protocol Buffers, Web Development, TCP/IP, Data Encryption, SMTP, Applied Cryptography, APIs, Containers, SSL, Transmission Control Protocol (TCP), API Design, Writing & Editing, Analysis, Prototyping, Geofencing, Middleware, Content Management Systems (CMS)
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
Choose your talent
Start your risk-free talent trial
Top talent is in high demand.
Start hiring