Ioana Dinu
Architect of Java Microservices
Experience
Jan 2022 - Jun 2023
6 monthsArchitect of Java Microservices
Cariad Volkswagen
- The client, an automotive company, had serious problems with the software architecture leading to customer dissatisfaction and decreased sales. They decided to upgrade the infrastructure to top-notch technologies.
- Conducted a thorough analysis of a 32-microservices architecture, culminating in formulating a comprehensive roadmap for transitioning to Java 17 and Spring Boot.
- Elevated on-time delivery rates by a substantial 70% through implementing advanced Java Technology. This involved generating precise stock projections and delivery timelines, contributing to improved customer satisfaction.
- Secured an impressive profit surge of 70 million by architecting a dependable, high-performance microservice.
- This microservice was crafted with a test-driven approach, achieving an impressive 85% test coverage ensuring reliability and functionality.
- Skills: AWS, Java 17, Spring REST, Hibernate, JPA, Spring Boot, Spring Batch, BDD Mockito, Swagger3, Jira, Confluence, Docker, Webflux, Datadog, Spring Security with JWT Tokens.
Oct 2021 - Jan 2023
1 year 4 months Netherlands
Senior Java Software Engineer
IBM Netherlands
- The client, a prominent retail corporation, aimed to enhance customer interaction and drive revenue growth. Consequently, they created a novel application that delivers real-time stock updates and suggests alternatives for out-of-stock items.
- Achieved a remarkable 90% reduction in instances of undelivered goods, which were initially believed to be in stock.
- Elevated on-time delivery rates by a substantial 70% through implementing advanced Java Technology. This involved generating precise stock projections and delivery timelines, contributing to improved customer satisfaction.
- Secured an impressive profit surge of 70 million by architecting a dependable, high-performance microservice. This microservice was crafted with a test-driven approach, achieving an impressive 85% test coverage, ensuring reliability and functionality.
- Skills: AWS, Java 17, Spring REST, Hibernate, JPA, Spring Boot, Spring Batch, BDD Mockito, Swagger3, Jira, Confluence, Docker, Webflux, Datadog, Spring Security with JWT Tokens.
Jun 2021 - Nov 2021
6 monthsSenior Java Software Engineer
Uniqa Software Services
- The insurance company client faced challenges in attracting and retaining long-term customers while increasing revenue due to an outdated architecture and flawed code within their Uniqa Loyalty Program application. These issues led to its underperformance, numerous defects, and difficulties in maintenance.
- Achieved a 50% reduction in deployment, updating, and maintenance time by spearheading a comprehensive architectural migration from Java EE 6 to the contemporary Java 11, Spring Boot and OpenApi CodeGen framework.
- Significantly improved application performance, achieving a 10x enhancement through a strategic redesign of the database structure and utilising Hibernate and Spring JPA.
- Ensured the retention of over 2 million contracts by addressing subpar code causing critical bugs. This was accomplished by initiating a refactoring process and executing a test-driven design architectural migration that achieved an impressive 85% code coverage.
- Skills: Java 11, Spring REST Hibernate, JPA, Spring Boot, DDD, BDD, Junit5, SQL, Swagger3, Jira, Confluence, Jenkins, OpenShift.
Dec 2019 - May 2021
1 year 6 monthsSenior Java Software Engineer
ServUsTech
- The client, Colt Technology - a world-class global network and voice provider, failed to increase revenue and provide contentment to existing clients due to accumulated technical debt due to a bad architectural design.
- Unlocked the potential of an extra $700m in sales in Q1 of ’21 by leading a full architectural revamping process, thus enabling 1-2 day delivery time for new feature requests (instead of weeks) while keeping infrastructure costs to a minimum.
- Increased app performance by having 4x faster API calls while using 25% less memory and 30% fewer database calls.
- Internet speed skyrocketed from 100GB/s to 400 GB/s.
- Ensured 100% stability in migration and zero major incidents by implementing a test-driven development approach, achieving over 80% code coverage.
- Skills: Java 8, Spring JPA, Spring Boot, Elastic Search, DDD, BDD Mockito, Junit5, Kafka, Oracle Sql NoSQL, Swagger3, Feign clients, SOAP, Microservices, Linux systems, Jenkins, Rancher CI/CD.
Jan 2019 - Dec 2020
1 yearLead Senior Java Engineer
ServUsTech
- The client, Suzuki - a Japanese automobile manufacturer, was struggling to reduce the employees' workload and win precious time due to the lack of an automated system for managing documents for their internal car parts orders.
- Saved over 2000 hours of work weekly by using this new, highly over Oracle DB to query the DB directly and quickly data access.
- Skills: JavaScript, HTML, Java 8, Spring JPA, Apache Camel, Oracle.
Apr 2018 - Apr 2019
1 year 1 monthSenior Java Software Engineer
ServUsTech
- The client, Medtronic - a global leader in medical technology, had a high debt after a massive investment in a real-time patient monitoring app that could not produce any income due to bugs causing crashes and inefficient code.
- Designed an application with three times faster response time, by discovering and fixing bugs, adding key database retrieval optimizations, reducing cyclomatic complexity, and designing efficient caching that resulted in a significant impact on the increased 2019 revenue with 11.7%, resulting in total revenue of $2.391 billion for this year.
- Skills: Java 8, Hibernate, ActiveMq, JPA, MySql, Thymeleaf, Spring MVC, Spring, SCRUM, Tomcat, Git.
Jan 2016 - Mar 2018
1 year 3 monthsSenior Java Software Engineer
ServUsTech
- The client, Motus App - providing reimbursement costs for miles driven by employees for work purposes, was on the verge of losing clients because of the high response time of their mobile and desktop APIs.
- Assured that 100% of the clients’ contracts with the company were secured long term by engineering from scratch a lightweight, 3 times faster response time mobile application that queries only the necessary data that was further mapped and returned using Rest APIs.
- Skills: Java 8, Thrift, Postgress, Spring, Hibernate, Spring JPA, Tomcat, Microservices, Rest, Agile lean, Spring Security, JWT Tokens, Active Mq, Kaftka Streams.
Jan 2015 - Dec 2016
1 yearLead Java Software Engineer
QuercusApp
- The client as the owner of a real-time office feedback app, did not manage to acquire customers due to slow and unstable application, crashing under 100 concurrent users.
- Drastically increased performance 10 times by redesigning the full application with modern technologies and a stable database design.
- Achieved startling stability and scalability in record time, handling 10k concurrent sessions effortlessly by building and leading a fast-paced team of 5 people into fully redesigning the architecture from the ground up to meet business requirements having separate environments for dev & demo deployments.
- Ensured a successful KPMG acquisition by being a key player in the sales process, holding technical presentations and contributing to marketing discussions.
- Skills: Java 8, Spring Boot, MySql, Spring with RESTful Apis, Hibernate, JPA & Security, Maven, Spring Security.
May 2015 - Dec 2015
8 monthsSenior Java Software Engineer
Betfair
- The client, an online betting company, failed to grow their user's platform and maximize their income by providing new features due to existing bugs in production on their financial transactions and regulators' microservices.
- Drastically improved the microservices performance by 25% and increased the income by 10% by putting all efforts into upgrading the JMS messaging system to a strong Kafka system interconnecting the Funds with the Regulator's microservices, and designing new performant features.
- Skills: Java 8, Kafka Streams, Postgress, Spring, Hibernate, Spring JPA, Tomcat, Microservices, Rest, Agile lean, Chef, Jenkin, CI/CD.
Jul 2013 - Apr 2014
10 monthsSenior Java Software Engineer
Betfair
- The client, an online betting company, failed to grow their user's platform and maximize their income by providing new features due to existing bugs in production on their financial transactions and regulators' microservices.
- Drastically improved the microservices performance by 25% and increased the income by 10% by putting all efforts into upgrading the JMS messaging system to a strong Kafka system interconnecting the Funds with the Regulator's microservices, and designing new performant features.
- Skills: Java 8, Kafka Streams, Postgress, Spring, Hibernate, Spring JPA, Tomcat, Microservices, Rest, Agile lean, Chef, Jenkin, CI/CD.
Jun 2012 - Jun 2013
1 year 1 monthJava Software Engineer
LiveRail
- The online advertising company's client, now part of Facebook, struggled to accelerate its income growth due to a lack of critical reports on viewers' profiles for ad targeting and the real-time number of delivered ads.
- Drastically increased the company’s income from $40M to $100M annually by designing a highly efficient algorithm to collect and aggregate the needed data, leading to a successful release in 2013.
- The major increase resulted in selling the company to Facebook with $500M in 2014.
- Skills: Java, threading, java nio, Netty, TCP, UDP, HTTP, SVN, Java Sax Parser, Spring Security, JWT Tokens, Kafka Streams.
Summary
I am an enthusiastic Java Architect and Contractor with 10+ years of professional experience. As a contractor, I approach projects with an entrepreneurial mindset and a solid determination to tackle software-related business challenges, like scalability, performance, and enterprise-level organization. One of the standout accomplishments in my career was the development of a Java application, a solo endeavour, which contributed to Colt Technology's revenue by a staggering $700M. My characteristic patience and effective communication skills enable me to foster collaboration and bring out the best in my team members.
Languages
Romanian
Native
English
Advanced
Education
Oct 2012 - Jun 2014
Babes-Bolyai University
Masters in Distributed Systems · Distributed Systems · Cluj-Napoca, Romania
Oct 2009 - Jun 2012
Babes-Bolyai University
Bachelors of Computer Science · Computer Science · Cluj-Napoca, Romania
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