Waldemar D. Email & Phone Number

San Francisco Bay Area

Chicago, Illinois, United States

-Led the team effort in modernizing a decade-old codebase, transitioning from BackboneJS, JQuery, and React with Redux to React with hooks and Apollo Client (GraphQL) in TypeScript. Orchestrated an incremental rewrite that seamlessly integrated existing legacy services and structures. Utilized Apollo Server to consolidate legacy PHP APIs into a unified, typed interface. Employed Prisma, Redis, DynamoDB, and Elasticsearch, introducing GraphQL Subscriptions for real-time updates. Upgraded… Show more -Led the team effort in modernizing a decade-old codebase, transitioning from BackboneJS, JQuery, and React with Redux to React with hooks and Apollo Client (GraphQL) in TypeScript. Orchestrated an incremental rewrite that seamlessly integrated existing legacy services and structures. Utilized Apollo Server to consolidate legacy PHP APIs into a unified, typed interface. Employed Prisma, Redis, DynamoDB, and Elasticsearch, introducing GraphQL Subscriptions for real-time updates. Upgraded infrastructure from EC2 instances to ECR containers on Fargate. This strategic transition significantly empowered junior developers to effectively contribute to new feature development.-Adopted a serverless backend infrastructure utilizing AWS AppSync, enabling the reuse of resolver code in Lambda functions. By leveraging the Serverless Framework and custom plugins, we navigated Lambda size limitations with Layers. This innovative setup facilitated seamless transitions between serverless and containerized backend services, enhancing our resilience to AWS downtime and improving stability during deployments.-Successfully transitioned the email system from Postmark to AWS SES, handling both inbound and outbound communications. This enhancement improved scalability and email management efficiency, reducing operational costs.- Developed standalone mini-applications in Docker containers and established a reusable component framework that adheres to established design principles.- Managed an incremental migration from RabbitMQ to AWS SQS, optimizing message queuing, and enhancing system communication efficiency and reliability.- Contributed to the development of a React Native application utilizing AWS AppSync and DataStore, aimed at ensuring robust data management and synchronization, including ChatGPT and Zoom API integrations.- Collaborated with Customer Support to resolve bugs and implement special customizations based on customer requests. Show less

Chicago, Il

• Developed major software engineering projects for clients, ensuring that system uptime met customer requirements by creating and designing necessary server infrastructure that generated $5M in annual revenue.• Built front-end and back-end architecture, interfacing with team members to plan, execute, and support intricate coding projects and refactor codebases for efficient technology implementation. • Engineered and realized a highly-scalable technology platform to serve ads on… Show more • Developed major software engineering projects for clients, ensuring that system uptime met customer requirements by creating and designing necessary server infrastructure that generated $5M in annual revenue.• Built front-end and back-end architecture, interfacing with team members to plan, execute, and support intricate coding projects and refactor codebases for efficient technology implementation. • Engineered and realized a highly-scalable technology platform to serve ads on websites with heavy traffic volumes, ensuring real-time data processing and reportable database management. • Designed and optimized sharded MySQL Database Schema with Triggers and Views, enabling the efficient display of analytical data for major client projects. Show less

Greater Chicago Area

- Architected and led the initial development of logistics/parking mobile application using serverless/functionless AWS infrastructure. Tech stack used: React Native (Expo, Apollo/GraphQL, Flow), AWS Amplify (AppSync, Cognito, Lambda, Postgres), CICD (Gitlab with custom Amplify build scripts). Mentored a group of 4 offshore team members.- Architected and developed a mobile application on existing back-end infrastructure by introducing GraphQL middleware on Azure Function. The main feature… Show more - Architected and led the initial development of logistics/parking mobile application using serverless/functionless AWS infrastructure. Tech stack used: React Native (Expo, Apollo/GraphQL, Flow), AWS Amplify (AppSync, Cognito, Lambda, Postgres), CICD (Gitlab with custom Amplify build scripts). Mentored a group of 4 offshore team members.- Architected and developed a mobile application on existing back-end infrastructure by introducing GraphQL middleware on Azure Function. The main feature of the app was offline functionality, which was written by customizing apollo client links and optimistic responses. Greenfield project, written using React Native with Typescript.- Feature heavy work on a Fintech application written on serverless architecture (Lambda, Federated Cognito, WebSockets over API Gateway). I initiated the transition of custom visualizations from monolithic D3 to React oriented D3 for reusability and testability. Lead an effort to transition from Redux store oriented implementation to cleaner view centered design with React Hooks and Apollo client. Wrote custom WebSocket transport layer for Apollo client to fit existing BE, and also to support any additional data sources to encapsulate data transport layer away from application business logic and view. Show less

San Francisco, California, United States

• Designed and developed foundational front-end architecture to convert the product into a scalable, single-page JavaScript application while supporting overall product development in an Agile Scrum environment. • Designed and implemented RESTful API and back-end worker queuing system to ensure optimal performance of the application. • Spearheaded a server transition, overseeing the establishment of Automatic Server Configuration using AWS Elastic Beanstalk to strengthen and upgrade… Show more • Designed and developed foundational front-end architecture to convert the product into a scalable, single-page JavaScript application while supporting overall product development in an Agile Scrum environment. • Designed and implemented RESTful API and back-end worker queuing system to ensure optimal performance of the application. • Spearheaded a server transition, overseeing the establishment of Automatic Server Configuration using AWS Elastic Beanstalk to strengthen and upgrade system architecture. • Overhauled and modernized technical processes by consistently conducting integration testing to streamline processes and incorporate new programming languages, thereby ensuring technological integrity.• Established and implemented company-wide performance metrics in coordination with outside consultants to drive sustainable growth.• Interfaced with employees, preparing them for development positions by training, mentoring, and leading them through critical company initiatives and projects. Show less