Sebastian W.
Backend Engineer
Experience
Jun 2023 - Feb 2024
9 monthsBackend Engineer
DB AG
- Part of the development and maintenance of a NodeJS-based backend application delivering Key Performance Indicator (KPI) information to clients
- Extracted KPIs from the database, refined and aggregated them within the system
- Enabled authenticated frontend applications to request data via REST and display responses through intuitive diagrams and charts
- Established a robust unit- and integration-tests pipeline for the system
- Conducted strategic refactoring to enhance testability and simplify the system in adherence to the KISS principle
- Implemented new features in an agile environment
- Technology Stack: NodeJS, PostgreSQL, Test Driven Development, Unit-Testing (Jest), GitLab CI/CD, Git, Redis, REST-API (Fastify), SSO, JWT validation
Sep 2021 - Mar 2023
1 year 7 monthsFullstack Engineer, Requirements Engineer
MHP
- Developed and maintained a Vehicle Information System importing streaming vehicle data via Kafka
- Refined data via business logic to avoid persisting unnecessary data and forwarded datasets to a third-party application
- Managed the integration of vehicle image generation by a third-party application and storage of generated images back into the system
- Replaced a long polling solution with a streaming integration from Kafka, addressing challenges of faster data consumption and slower image processing to prevent flooding the third-party application
- Technology Stack: Java 8/11, Spring, REST-API, SQL, Kafka, caching mechanisms, GitLab CI/CD, unit-testing, Splunk monitoring and dashboards, Test Driven Development
Jan 2021 - Sep 2021
9 monthsBackend Engineer of the rule engine micro-service
MHP
- Developed an Online Car Configurator allowing users to customize vehicles via a web frontend with a real-time visualization engine
- Designed and implemented microservices in NodeJS/TypeScript based on NestJS framework
- Designed and developed a rule engine to determine the validity of user-selected options using rules written in Boolean algebra provided by a third-party application
- Imported third-party application rules into the rule engine to resolve user requests and validate configurations
- Technology Stack: NodeJS, TypeScript, Google Cloud Functions, NestJS, microservices, REST-API, SQL, unit-testing, Terraform, Test Driven Development
Jan 2020 - Present
5 years 9 monthsSoftware Architect and Backend Engineer
CGIBackgrounds
- Developed a website and backend service to manage HDRi backgrounds, enabling users to browse, purchase, and download assets
- Built a cloud-native AWS platform using Lambda functions for all functionality
- Implemented an import pipeline to move and rename files, extract keywords from EXIF/IPTC metadata, generate thumbnails, and create entries in DynamoDB
- Implemented subscription handling via Stripe API and consumed events to handle error cases
- Technology Stack: AWS, NodeJS, TypeScript, Serverless, AWS-CDK, Terraform, GraphQL, REST-API, Angular, RxJS, unit-testing, Test Driven Development
Aug 2019 - Dec 2019
5 monthsConsultant and Business Process Model Developer
MHP
- Conducted business process analysis to detect missing information in tooling and interdepartmental communications
- Described business processes using BPM diagrams
- Technology Stack: Enterprise Architect, BPM
Jul 2016 - Jun 2019
3 yearsSoftware Architect of the application, Developer of the rendering micro-service
Mackevision
- Architected and developed a cloud-native platform to generate high-quality 2D imagery from pre-generated 3D assets via VRay rendering engine in AWS
- Provided users with real-time previews streamed via WebSockets
- Implemented application load balancers and EC2 instances with on-demand scaling to handle varying user load
- Managed a queue for batched high-quality image rendering by dynamic EC2 instances
- Technology Stack: UML, sequence diagrams, component diagrams, REST-API, NodeJS, Java, Spring Boot, Hibernate, TypeScript, NestJS, JWT, Angular, RxJS, Terraform, Test Driven Development
Nov 2015 - Jun 2016
8 monthsBackend Developer
hydra newmedia GmbH
- Developed REST microservices in NodeJS for a vehicle inventory system displaying vehicle counts and metadata for site administrators
- Integrated external APIs and implemented webhooks for external consumers
- Technology Stack: REST-API, NodeJS, TypeScript, JWT, Test Driven Development, MongoDB, ElasticSearch, Swagger/OpenAPI
Oct 2013 - Oct 2015
2 years 1 monthWeb Developer
Synergetic Agency AG
- Developed and maintained PHP-based e-commerce applications
- Built a product information management (PIM) system in C# with REST-APIs and an AngularJS frontend
- Developed a newsletter layout tool with NodeJS and Electron, enabling users to create newsletters via drag-and-drop UI components
- Technology Stack: REST-API, NodeJS, Test Driven Development, Electron, AngularJS, Magento, WebAPI, MySQL, MSSQL
Languages
German
NativeEnglish
IntermediateCertifications & licenses
CPSA-F iSAQB® Certified Professional for Software Architecture – Foundation
iSAQB
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