Stephen Maina Email & Phone Number

Austin, Texas, Us

Teaneck, New Jersey, Us

Quality Engineering1. Implementing a new model for organizing resources as Pods – autonomous teams that own theultimate responsibility of delivering a product by shifting from process-driven to a product-driven model.2. Identifying and discussing quality gaps and improvement opportunities in the DevOps pipeline, and formulatingmeasurable goals for quality engineering.3. Designing amaturity model andincentive model for integration with the new CICD platform to attract teams overto the new pipeline and therefore benefit from unified governance and a shared experience.4. Identifying characteristics, sources of data, collection and processing of different metrics to create a holistic pictureof where teams are in the quality journey. DORA metrics was included as well5. Started building up a testing platform to allow teams to experiment with their product migration before switchingover to the new pipelines.

Teaneck, New Jersey, Us

Platform Engineering1. Creating a state-of-the-art, end-to-end, tech-stack-agnostic CICD platform to be deployed across the entireorganization as Discover Financial Services transforms into cloud computing2. Working to automate migration of applications from the existing deployment infrastructure to a new cloudenvironment using an architectural pattern called a migration factory3. Transforming the pipeline architecture to react to events generated by external systems through webhooks whenpipeline stages are completed, as opposed to an imperative pipeline that actively polls these external systems forinformation4. Smoke testing and integration testing migrated products to ensure that they continue to work as expected5. Building supporting infrastructure around the pipeline for collection, analysis and dissemination of specific CI/CDmetrics, for example audit artifacts, DORA metrics (DevOps Research & Assessment)

Chicago, Illinois, Us

1. Developed solution for OAuth2 federated logout across multiple devices/browsers leveraging AWS Cognito, AWS SNS, Socket.io, and Postgres, and all this in a multi-pod Kubernetes deployment2. Rolled out a migration strategy from Java 8 and into Java 11 from an application’s build files and through the deployment pipeline3. Implemented feature toggle functionality to enhance deployments by eliminating the pain-points experienced4. Developed GraphQL Java client which works by discovering the JSON schema of an existing endpoint, transforms this to a GraphQL DSL, generates all domain classes and stubs out client endpoints to the GraphQL schema5. Rolled out an integration strategy with Kafka and developing data lake solution using Kafka connect and leveraging KSQL and GraphQL to handle requests of any form or shape for data existing in various topics6. Rolled out modularization strategy for backend applications to accommodate multi-tenancy requirements and also streamlined the application packaging pipeline to produced customized artifacts based on a specifically targeted client7. Implemented integration strategy to allow 3rd party application users to get automatically federated into an existing application and be able to use it as a different type of tenant8. Working closely with company leadership and across departments to handle cross-cutting concerns and requirements with goal to stay in close alignment and maintain a shared focus9. Elevating my team to stay motivated and sharp through open dialog and fostering creativity through a weekly tech-talk where presenters may prepare and give presentations around any topics they may have interest in

Seattle, Wa, Us

Calculating the "quality score" value for vendors on Expedia websites using Big Data techniques.Massive revenue implications that were dependent on the ranking in Expedia websites' listingRanking was determined by the quality score calculated from a variety of data inputs, including and not limited to: - listing price- listing ratings- customer reviews- listing quality (descriptions provided, accuracy of information, images catalog)- quality score history- listing amenitiesExecution strategy- Spark is able to make use of existing Hadoop HDFS which provided an easy migration path from Hadoop to Spark- Used Spark framework instead of Hadoop framework- Used Spark batch with notebooks (interactive mode) instead of Hadoop mapReduce- Used Object storage (S3) instead of Hadoop HDFS- Used Servlerless functions (lambdas) instead of Hadoop YARN- Used data science libraries like Numpy and Pandas for data cleaning, preparation and analysis- Spark has built-in machine learning capabilities (MLlib) which Hadoop conspicuously lacks- Ability to rerun jobs when a certain threshold of new data arrives or when corrections are made to the data by the data science team

Charlotte, Nc, Us

Converted Java projects to Java 8 and mavenMigrated Java applications out of Weblogic to Spring BootDesigning and implementing React UI admin interface for FX teamsStreamlining React development workflow with Nodejs and middleware for logging and testing

Madison, Wi, Us

Designed and created REST API microservices to drive a Modern JavaScript based UI and replace the existing monolithic legacy web app.Identifying functional boundaries in the existing code base to begin splitting functionality into smaller, self contained services.Migrating massive amounts of SQL from mainframe COBOL to distributed data access microservicesScreen scrapping IMB mainframes for logging output to help with SQL migrationDocumenting new API and developing training material for the massive workforce which would use the new application

Re-writing the backend of one web service for the largest electronics chain in US. Working specifically with RESTFUL web services that can scale upwards, to excess of the 10K requests limit per second. Using unconventional (but perfectly functional) approach to caching and maintaining cache data. Using Java-6 concurrent package to handle the highly multi-threaded scenarios demanded by the business requirements. Leveraging servlet 3.0 and the creative genius of SQL server and Oracle magic.

Creating modern solutions for businesses in the automobile industry. Integrating websites with social media. Pushing backend concerns away from the hosting servers to distributed RESTful web services. Leveraging lightweight servlet containers like Tomcat for the web services and serving JSON and XML content with clean API's. Using JPA, Spring, Hibernate, Lucene and Oracle or the backend. Harnessing javascript and browser capabilities to achieve uniform behavior for 'back button' on every browser while using ajax.

Glen Allen, Va, Us

Worked on a e-commerce project for a major cruise-line, with features like booking/reservations/appointments/excursions/gifts/online payment. Rebuild the application from the ground up using the best technology that met the business requirements. Ajax-ified the new system to move user experience to the next level.

Enhancing the point-of-sales system for store's pharmacy checkout by integrating ID scanning and keeping track of prescribed medication that had the potential for misuse.Replacing existing C-based POS with a Java-Based, NIO, asynchronous system, with a custom layer 7 TCP protocol for enhanced security and addressing specific customer needs.

Master Of Science (Ms), Computer Science

Bachelor Of Science (Bsc), Mechanical Engineering