08/06/2026 updated
100 % available
Senior QA Automation Engineer Java Backend Developer | Selenium REST Assured Spring Boot | 13+ years
Erdemli, Turkey
Worldwide
Çanakkale OnSekiz Mart Üniversitesi Computer EngineeringAbout me
Senior QA automation engineer and Java backend developer. I build test automation frameworks and Spring Boot backends for payment, fintech and telecom platforms, and I run several production SaaS products of my own. Direct communication, structured reporting, no surprises.
Java (Programming Language)Test AutomationIPTVJava API For RESTful Web Services (JAX-RS)Apache JMeterPostgreSQLAWS CLISeleniumTest ManagementTestngSpring BootCypress (Programming Language)BackendBackend ProgrammingPytest
Senior QA Automation Engineer and Java Backend Developer with 13+ years of
experience in telecommunications, contact centre platforms, fintech and
blockchain payment systems.
TEST AUTOMATION
I design, build and own test automation frameworks from scratch. Core stack:
Java, Selenium WebDriver, Appium, REST Assured, Karate, TestNG, JUnit, Cucumber,
Maven, Gradle. I write API, integration, regression, end-to-end and system tests,
and integrate them into CI pipelines with Jenkins and GitHub Actions. Test
management with Zephyr Scale, Jira, Confluence and Xray. Experience with test
strategy, test planning, defect management, risk and escalation handling, and
reporting test progress to project leadership. I have led QA activities in
complex multi-stakeholder projects and mentored junior engineers. I also teach
Java/Selenium and Appium test automation courses.
DOMAIN EXPERIENCE
Blockchain payment infrastructure: Bitcoin wallet backend, Ethereum and Solana
wallet services, ERC20 token handling, transaction batching, message queue
recovery. Fintech: payment gateways, banking-as-a-service APIs, account and
payment flows. Telecommunications: IPTV platforms. Contact centre platforms
with XMPP-based messaging.
BACKEND DEVELOPMENT
Java and Spring Boot backend development, Java 21, Spring Boot 4.x, REST API
design, PostgreSQL, JPA/Hibernate, Flyway migrations, multi-tenant SaaS
architecture. Secondary experience with Node.js and NestJS. Cloud and
infrastructure: AWS EC2, RDS, S3, SES, Polly, Route 53, Amplify, Systems
Manager. Also worked with Azure Speech services. I have built and operate
several production SaaS products end to end, including a multi-tenant email
marketing platform and a multi-language learning platform.
WAYS OF WORKING
Agile and structured project environments, distributed and offshore teams,
Git-based workflows, code review, English at professional working level.
Available for freelance engagements, invoicing through my registered company
in Turkey.
Experience
Professional experience10+ years
Freelancer since2015
Languages
EnglishNative speakerSpanishGood
Project history
Language learning platform where users study Russian, German, English
and Spanish through live TV channels and video-on-demand content with
interactive transcripts.
* designed and implemented the backend services on Spring Boot, covering
content catalogue, user progress, transcript synchronisation and
course modules;
* built a digital coursebook module generating narrated dialogs through
AWS Polly text-to-speech;
* implemented word-level audio-text synchronisation by parsing Polly
Speech Marks into a timing index, powering a karaoke-style reading mode;
* integrated Azure Speech pronunciation assessment to score learner
recordings at phoneme level;
* built a role-play mode allowing learners to take one side of a dialog
with automated playback of the other;
* designed the PostgreSQL schema and REST API consumed by web and native
Android clients;
* migrated the full platform between AWS accounts without user-facing
downtime;
* recovered a production instance after filesystem ownership corruption
using AWS Systems Manager;
* operated multiple backend services on a single EC2 instance with
port-based separation.
AI-powered study coach web application for students, providing
personalised learning guidance and progress tracking.
* designed and implemented the backend REST APIs on Spring Boot,
covering user accounts, study plans, progress tracking and
session history;
* designed the relational database schema and data model for
learner profiles and coaching sessions;
* integrated large language model APIs to generate personalised
study guidance, including prompt design, context management
across sessions and handling of streaming responses;
* implemented rate limiting and cost controls around LLM usage;
* built the React frontend for the web application;
* handled deployment and operations on AWS.
Telehealth platform for remote medical consultations, home healthcare
services and cancer patient follow-up.
* designed and implemented the backend REST APIs on Spring Boot, covering
appointment scheduling, patient records, consultation sessions and
practitioner management;
* designed the relational database schema for patients, practitioners,
appointments and medical history;
* integrated Agora for real-time video consultations between patients
and doctors, including session lifecycle handling;
* built the React frontend for the web application;
* led a team of three developers — two mobile and one frontend —
coordinating delivery across web, iOS and Android clients;
* defined API contracts consumed by all three client applications and
handled versioning as features evolved;
* participated in requirement analysis with the founders and translated
product requirements into technical specifications.