Eldar Jahijagić

Working as Principal Software Engineer

Technical Lead, Senior Software Engineer
Unifonic · Dubai, UAE · Nov 2021 - Jan 2022
Led a company-wide initiative, deploying the entire platform and all its services, systems, and components on a dedicated Oracle in-country cloud
achieving a cloud-agnostic platform. Deploying systems to Oracle in KSA, and AWS in Bahrain.
Collaborating and leading multiple teams, planning with engineering, product, and compliance departments, and analyzing data compliance (GDPR)
Designed systems for Replication, Failover, Load Balancing, and Disaster Recovery, and successfully deploying the entire platform in a multi DC -
Active/Passive setup.
Designed and implemented microservices for API Traffic Routing and User Federation, depending on the country, user preferences and compliance.
Designed and architectured systems for scalability and high availability. Implementing Lua & Java services, using Redis, PostgreSQL, and Elasticsearch.
Senior Software Engineer
Implementing a Single API solution - an API Gateway using Kong, Nginx, and Lua. Successfully handled up to a million of API requests per minute.
For the gateway, I implemented custom features such as monitoring, service vitals, distributed tracing, access control, IP Whitelisting, and ratelimiting.
Designed and implemented an Identity and Access Management solution for the entire platform, using Keycloak, in addition to Java microservices.
Developed both backend and frontend applications for creating and managing API Keys - built a Maven Java SDK and library, for other teams to use,
for verifying, analysing, and monitoring the said API Keys, tokens, claims and privileges.
Designing and implementing Service-to-Service Authentication for all internal service communication, and securing critical endpoints with latest
OAuth and service auth. standards.

• Lead, actively worked on and maintained custom internal tools for monitoring core
business services
• Designed and implemented efficient large-scale Java services, for high tarffic data
consumptionanalysis and indexing with Hazelcast, Kafka, RabbitMQ, Elastic and
MongoDB
• Orchestrated containerized service deployments, across multiple instances and
DCs, with Jenkins, Maven, Docker, running on Centos and RHEL
• Implemented Java services that integrated with 80 different telecom providers’
APIs, for data consumption and analysis etc.
• Monitored and implemented alerting with Prometheus and Grafana
• Implemented scripts with bash and Python
• Coordinated within an agile scrum team

• Started freelancing early 2016 together with few friends, and still sometimes
working with clients and connection made throughout the years
• Worked on different stacks, mostly .NET, Spring and Angular
• Implemented a web application for UK teachers and online teaching, webinars,
forum etc. - written in Java and mostly PHP/Laravel
• Implemented a Taxi application for online registering taxi companies, ordering a
taxi - web written in Angular and an android application in Dart/Flutter
• Used HTML, CSS, Sass, Less, node, npm, Javascript and Typescript for various
short-term frontend tasks and projects
• Worked with Azure, AWS, Linux, MySQL, SQL Server for various server and
database tasks

• Coding, testing and maintaining client oriented web and mobile applications,
implemented in mostly .NET, PHP, Angular, Flutter and Android
• Worked closely with other business analysts, development teams and
infrastructure specialists to create software solutions
• Writing integration and unit tests for different tech. stacks
• Maintained app hosting infrastructure, setting up CentOS, RHEL, Microsoft Azure,
Gitlab, Jenkins and Docker
• Implemented custom enterprise web management application written in PHP
• Implemented Angular/Python web application for streaming live media from on-
premise camera devices
• Worked on web and mobile application for food delivery