Alexandros Nafas
Verified Expert in Engineering
Software Developer
With over ten years of experience in software engineering working with numerous major clients in various industries, including logistics, tourism, and adtech, Alex has the skills to deliver complete solutions to difficult problems. He enjoys working on various tasks, from the front end to the back end, data engineering, and infrastructure. However, Alex is most intrigued by figuring out what the client really wants and how he can deliver something of value to them.
Portfolio
Experience
Availability
Preferred Environment
GitLab, Jira, Git, Slack, WebStorm, IntelliJ IDEA, MacOS, Linux
The most amazing...
...project I've led was building a data pipeline that analyzed traffic quality and blocked fraudulent sources in real-time, resulting in a 30% reduction in fraud.
Work Experience
Senior Java Developer
Mambu
- Worked as part of a team to develop a new financial product for Islamic profit sharing.
- Designed and implemented various system components, including the API, the computation pipeline, and data ingestion.
- Collaborated with the product owners and clients to identify and fix bugs.
Tech Lead
Syngenta - Digital Product Engineering
- Took over a project of 13 microservices from the previous team and was responsible for discovering the architecture.
- Supported a team of front-end engineers, requesting bug fixes and new features being implemented.
- Mentored new engineers coming into the project and guided their implementations. Handled the final code approval.
- Defined a CI/CD across four environments involving Jenkins, AWS CodeBuild, and GitHub Actions.
- Worked on migrating data from the legacy platform into the new one, which involved understanding the business model and making the necessary transformations.
- Built a small data pipeline, which pulled data out of the application and ingested it into a data lake used to power reporting tools.
Principal Software Engineer
Priceline
- Implemented new integrations with Booking.com updated APIs.
- Containerized and migrated apps from on-prem servers to GKE.
- Replaced calls to the legacy Oracle database with Netflix Hollow in-memory cache solution.
- Migrated CI/CD processes from Bamboo to GitHub Actions.
Technical Lead
Glispa Global Group
- Served as a technical lead on the Glispa Performance Network, one of the top advertising affiliate networks with numerous partner integrations, earning more than a million dollars in revenue per month.
- Worked as a front-end developer building external analytics dashboards and maintaining the company's main internal platform in Angular.
- Acted as a data engineer, automating event data ingestion from Kafka, using Python and Scala Spark to process events and present results to dashboards built with Angular and Turnilo.
- Led a big project of building a data pipeline that analyzed traffic quality and blocked fraudulent sources in real-time. The result was a 30% reduction in fraud as well as freeing up the account managers who had to do this task manually before.
- Used Kubernetes and GitLab CI for automating the deployment of all microservices.
- Worked as a scrum master and helped clarify processes and ease the transition of the Athens department from being a startup to being part of a large organization with multiple departments and stakeholders around the world.
Senior Full-stack Engineer
Avocarrot (Glispa Global Group)
- Maintained and implemented new features on Avocarrot, a leading ad exchange network with hundreds of clients and systems handling thousands of requests per second.
- Worked as a full-stack engineer, implementing web applications with Node.js and Java on the back end and Angular and Ember.js on the front end.
- Served as a data engineer and built ETL processes in Python and Scala, powering internal and external reporting and billing.
- Contributed to the Dockerization and migration of the whole stack of more than 20 microservices to Kubernetes.
Full-stack Engineer | Technical Lead
Project Beagle (FTI group)
- Led a team of highly skilled engineers to build an automated bed bank for one of the largest tour operators in the world.
- Served as a core member in the team that implemented the high throughput and low latency search engine built with microservices in Java Spring and Scala for hotel room availability and prices.
- Wrote and optimized SQL queries to achieve lower latency.
- Built new products in AngularJS and Angular 2 as a front-end engineer.
- Served as a scrum master, helping the team overcome obstacles and facilitating the Scrum methodology throughout the company.
- Acted as a product owner and communicated with business clients, clarifying requirements to be implemented before handing them over to the development team.
- Wrote many end-to-end tests, helping to automate the process of testing and reduce the possibility of releasing bugs to production.
- Helped the company embrace a DevOps mindset, transitioning from a fixed-release cycle to continuous deployment so that features could get shipped to production faster.
SAP Developer
Step One Consulting SA
- Worked on the end-to-end material management and warehouse management implementations for large Greek and international companies.
- Connected two SAP systems from different companies to achieve electronic invoicing (e-invoicing).
- Designed and implemented a mobile sales app for sales representatives to be able to complete orders remotely.
Experience
Updoc Health-tracking App for Android and iOS
[Open-source Contribution] Apache Airflow
https://github.com/apache/airflow/pull/7127[Open-source Contribution] Kafka Connect
https://github.com/confluentinc/kafka-connect-hdfs/pull/283Education
Master's Degree in Computer Science and Engineering
University of Patras - Patras, Greece
Bachelor's Degree in Computer Engineering and Informatics
University of Patras - Patras, Greece
Certifications
Functional Programming Principles in Scala
Coursera
Machine Learning
Coursera
Skills
Libraries/APIs
REST APIs, Node.js, OpenAPI, React, NgRx, PostgREST
Tools
Git, GitHub, Apache Druid, Cloud Dataflow, SonarQube, Apache, Apache Beam, Ansible, IntelliJ IDEA, WebStorm, Slack, Jira, GitLab, RabbitMQ, BigQuery, Apache Airflow, GitLab CI/CD, Confluence, Google Kubernetes Engine (GKE), Amazon EKS, Jenkins, AWS CodeBuild, Kafka Streams, Amazon Simple Queue Service (SQS), Amazon Simple Notification Service (Amazon SNS)
Frameworks
Spring, Angular, JUnit, Mockito, Vert.x, Hibernate, Ionic, Spark, Apache Spark, Spring Boot, Hadoop, Ember.js, Akka, Jest
Languages
Java, SQL, Java 11, Bash Script, JavaScript, TypeScript, Scala, HTML, ABAP, Python, PHP, CSS
Paradigms
Scrum, Continuous Delivery (CD), Unit Testing, Agile, Microservices, REST, DevOps, Continuous Integration (CI), Continuous Deployment, ETL
Platforms
Docker, Apache Kafka, Firebase, Kubernetes, Linux, Amazon Web Services (AWS), Google Cloud Platform (GCP), Ubuntu, Oracle, MacOS, Oracle Database, AWS Lambda, Azure
Storage
MySQL, PostgreSQL, Relational Databases, Druid.io, MongoDB, NoSQL, Data Pipelines, Cassandra, Google Bigtable, BigTable, HBase, Amazon DynamoDB, Redis
Industry Expertise
Healthcare
Other
Google BigQuery, Back-end, Full-stack, APIs, Software Development, Integration Testing, Architecture, Data Engineering, CI/CD Pipelines, Metabase, Monitoring, Systems Monitoring, Hospitality, Data Architecture, Big Data, Data Warehousing, Cloud Architecture, GitOps, DevOps Engineer, Infrastructure as Code (IaC), Distributed Systems, Apache Cassandra, SAP, API Connectors, Lambda Functions, Stream Processing, Real-time Streaming
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