Jens Grassel
Software Architecture, Backend Development
Experience
May 2023 - Present
2 years 3 monthsSoftware Architecture, Backend Development
Shijou GmbH
- Marketplace Solution / eCommerce Retail
- Scala, Python, http4s, next.js, Elasticsearch, Postgresql, AWS
Sep 2022 - May 2023
9 monthsBackend Development
Toll Collect
- Mobility sector
- Analysis and processing of sensor data as well as quality assurance of the algorithms used within a cluster solution based on Spark, Kafka, Cassandra, and PostgreSQL, implemented in Scala and Java.
- Scala, Java, Spark, Kafka, Cassandra, PostgreSQL, Docker, Scrum, Jira, Confluence
Oct 2021 - Aug 2022
11 monthsBackend Development
Fashion Digital GmbH & Co. KG – P&C
- Backend development with Scala and Akka for the Product Data team in the E-Commerce division, further development of the platform with Kotlin, Cloud Bigtable.
- Scala, Akka, Kafka, Java, AWS Cloud, Kubernetes, Docker, Scrum, Jira, Confluence, GitHub, Kotlin, Cloud Bigtable, GCP
May 2021 - Sep 2021
5 monthsBackend Development
EWE AG
- Porting existing REST services and AWS Lambdas into a new AWS infrastructure as well as designing and implementing new services.
- Python, Flask, RabbitMQ, DocumentDB, AWS, Microservices, REST-API, Docker, Kubernetes, CI/CD, GitLab, Scrum
May 2020 - Apr 2021
1 yearIoT – Research Project
- Scala, htttp4s
- Internet of Things and integrative organizational design: impact on organization and employees
May 2020 - Apr 2021
1 yearMarketplace Solution / eCommerce Retail
Shijou GmbH
- Scala, Python, http4s, next.js, Elasticsearch, Postgresql, AWS
May 2020 - Apr 2021
1 yearProduct Development Sellerforge SaaS
Wegtam GmbH
- Scala, Python, http4s, Postgresql, Stripe
Jan 2020 - Apr 2020
4 months Switzerland
Project Planning, System Architecture, Backend Development
carIT AG
- Analysis and code auditing of a car auction platform based on Java and Spring.
- Initialization and planning of a fundamental modernization and consolidation of numerous detached sub-platforms.
- Concept development for refactoring the entire IT infrastructure including hosting.
- Java, Jenkins, MySQL
Mar 2018 - Dec 2020
1 year 10 monthsBackend Development
Parfümerie Douglas GmbH
- Maintenance and further development of the online shop based on the Play Framework and Hybris.
- Introduction of functional programming in Scala for the backend teams.
- Development of new services for data integration tasks.
- Scala, Akka, Python, Playframework, Docker
- Hybris E-Commerce platform in Java
- Data aggregation, data analysis and data provisioning
Oct 2017 - May 2018
8 monthsDevelopment of a Big Data Environment
Centogene AG
- Design and development of a big data environment for processing large volumes of laboratory measurement data for analysis and identification of biomarkers.
- Integration of raw data into processing pipelines via Flink, Cassandra, Kafka.
- Python, Scala, Akka, AWS, MySQL, Apache Zeppelin, Apache Flink, Kafka and Cassandra
May 2017 - Dec 2017
8 monthsBackend Development
Recogizer Group
- Development of new and extension of existing microservices in the field of IoT data as a foundational platform for ML systems.
- Python, Scala, Elixir, Akka, Docker, CI/CD pipelines
Sep 2016 - Mar 2017
7 monthsBackend Development
Free2Move (Carjump)
- Analysis and further development of an existing service architecture as well as supporting new developers in onboarding.
- Design and implementation of new services based on given problem statements.
- Scala, Python, Playframework, Google Cloud, data aggregation and data analysis
Mar 2015 - Sep 2016
1 year 7 monthsBackend Development
The Zene AG
- Development of services and search indexes to provide web search and image search for a website and an app via REST API.
- Scala, Java, Elasticsearch
Jan 2014 - Jun 2015
1 year 6 monthsProduct Development
Wegtam GmbH
- Tensei-Data
- Scala, Akka, Playframework
- Tool for data aggregation and data analysis
- Wegtam Search Agent
- Java, Elasticsearch
- Enterprise search solution
Jun 2012 - Present
13 years 2 monthsCTO / Founder
Wegtam GmbH
- Tensei-Data – Data integration
- Wegtam Search Agent - Enterprise Search
- Core technologies: Scala, Akka, Play, Elasticsearch
Feb 2011 - Oct 2013
2 years 9 monthsTechnical Director
Telematika GmbH
- Programming, development, CRM, DMS, ERP, CMS, e-learning
Sep 2008 - Jun 2010
1 year 10 monthsProject Management
nexico Consulting GmbH
- Leadership, programming, data mining, BI, development
Nov 2006 - Jun 2010
3 years 8 monthsFreelancer in the field of Internet services and software development
- Programming, development, web applications, consulting
Mar 2001 - Mar 2005
4 years 1 monthTrainee
Vinci Energies - Controlmatic GmbH
- Automation technology, programming, development
Languages
English
Advanced
German
Advanced
Russian
Advanced
Spanish
Advanced
Education
Sep 2002 - Aug 2007
University of Applied Sciences Wismar / University of Rostock
Diploma, Business Informatics · Rostock, Germany
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