Cosmin-marian A.
Java Developer
Experience
May 2022 - Present
3 years 8 monthsJava Developer
Grubhub
- Successfully built a critical payment service responsible for over 30% of the checkout traffic, collaborating with 10+ external teams/systems. This service reduced fraudulent loopholes, removed unnecessary failure points, and lowered the workload on other services.
- Built a centralized partnership microservice for managing ongoing partnerships without engineering team intervention.
- Leveraged software engineering expertise to design and develop high-impact features for diverse partnerships, driving substantial growth in subscriber acquisition and retention rates.
- Implemented cost-saving measures by conducting efficiency tests and optimizing services, resulting in significant reductions in overall service costs while maintaining high performance and reliability.
- Maintained, scaled, and optimized the cost efficiency of specific EC2 instances by conducting load tests, identifying resource utilization patterns, and applying performance enhancements to ensure optimal scalability and cost savings.
- Developed and used Docker images to effectively test microservices, ensuring seamless deployment and consistent testing environments across different platforms and configurations.
- Technologies: Java 11/17, Guice, Apache Cassandra, AWS, Jenkins, Spinnaker, Docker, Gatling, Kafka.
Sep 2020 - May 2022
1 year 9 monthsJava Developer
Playtika
- Contributed to one of the teams that developed multiple features for the World Series of Poker, a game with over 10 million players and 500k+ daily active users.
- Maintained and added new features to an existing monolith legacy system without affecting game performance or quality.
- Migrated existing functionalities to microservices without business downtime. Developed multiple concurrent microservices to handle periodic in-game events that awarded players rewards based on a progression system. This reduced production release time for new events by 50%.
- Developed a new mini game as a concurrent microservice to increase player retention. The mini game used a flexible solution for different behaviors based on customizable configurations that could be updated without downtime via a web interface.
- Conducted comprehensive performance testing with Gatling to assess the scalability and responsiveness of each service under various load conditions. Executed detailed functional testing with WireMock to ensure reliability and correctness, validating multiple scenarios and edge cases.
- For each new microservice, collaborated with the Business Department to understand product requirements and identify critical components for a fast, reliable, and revenue-generating solution.
- Worked with Software Architects to create generic approaches for new microservices.
- Technologies: Google Guice, Java 11, Spring Boot, Spring Cloud, Spring WebFlux, Aerospike, Kafka, AWS, Redis, ELK, WireMock, Gatling.
Jul 2018 - Sep 2020
2 years 3 monthsJava Developer
Sparktech
- Extended AI project: Developed a web application to manage and interpret different Machine Learning experiments and provide accuracy results based on input data.
- Extended AI project: Created a job manager using a messaging queue (Google Pub/Sub) for interaction between the core application and the Machine Learning component.
- Extended AI project: Used Google Cloud tools such as Cloud Storage and various SQL instances for data storage.
- Extended AI project: Used GraphQL as an alternative to REST API for better handling of objects in the front-end component.
- Extended AI project: Contributed to all phases of the Software Development Life Cycle following Agile methodology, including bug fixing and issue investigation.
- Extended AI project: Participated in code reviews.
- Extended AI project technologies: Java 11, Spring Boot, Hibernate, Maven, PostgreSQL, Google GCP, Google Pub/Sub, GraphQL.
- Data governance application project: Worked on a data ingestion application composed of multiple Java modules, each handling different file transfer methods (FTP, SFTP, HDFS).
- Data governance application project: Implemented features to store various reports as metadata in Apache Atlas and Elasticsearch.
- Data governance application project: Collaborated with the Big Data department to create pipelines with Apache Airflow using the Java modules.
- Data governance application project technologies: Java 8, Spring Boot, Hibernate, Maven, PostgreSQL, Elasticsearch.
- Automotive application project: Worked on a complex web application for a large automotive company. The app stores millions of labeled data points about car issues that can be grouped, cataloged, and filtered.
- Automotive application project: Worked in an Agile format, interacting with product owners in the Scrum process.
- Automotive application project technologies: Java 8, Spring Boot, Hibernate, Maven, OracleDB, Apache Solr.
- RESTful Web Server in Spring project: Developed an application for extracting specific data from candidates’ CVs using Machine Learning algorithms to provide a score that assists recruiters in choosing the best candidate.
- RESTful Web Server in Spring project technologies: Spring Boot, Kafka, Livy, HBase.
Jul 2017 - Oct 2017
4 monthsJava Developer Intern
Ymens Teamnet
- Developed various mini-projects during Java and AngularJS trainings.
- Implemented, tested, and documented an authentication component for a fitness web application.
- Created different graphics with the D3 library for user statistics visualization.
Summary
Enthusiastic Java developer with a strong desire to continue growing in a professional environment. I enjoy working in a challenging environment where I can gain new skills and deliver great results.
Languages
Romanian
NativeEnglish
AdvancedFrench
ElementaryEducation
Oct 2018 - Jul 2020
Faculty of Mathematics and Computer Science Bucharest
Software Engineering · Bucharest, Romania
Oct 2015 - Jul 2018
Faculty of Mathematics and Computer Science Bucharest
Computer Science · Bucharest, Romania
Certifications & licenses
Adobe Java Dev Bootcamp
Adobe
Public Speaking Training
ASMI
Fundraising Training
ASMI
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