Niksa Klecak, Developer in Belgrade, Serbia
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Niksa Klecak

Verified Expert  in Engineering

Bio

Niksa is a seasoned senior software development engineer in test (SDET) with over 12 years of experience delivering successful projects for industry leaders like Cisco and Adobe. He excels in UI, API, and mobile automation, setting up CI pipelines, and ensuring early bug detection for enhanced software reliability. Niksa is proficient in major automation tools.

Portfolio

Toptal
JavaScript, Python, Manual QA, QA Testing, UI Automation, REST API Automation...
Adobe
Docker, CI/CD Pipelines, API Testing, Automated Testing, Software QA...
Imfiy BV
Java, TestNG, CI/CD Pipelines, QA Automation, TypeScript, GitHub, Playwright...

Experience

  • QA Automation - 13 years
  • Quality Assurance (QA) - 13 years
  • TestNG - 8 years
  • Jenkins - 6 years
  • Selenium - 5 years
  • JavaScript - 3 years
  • Cypress - 2 years
  • Appium - 1 year

Availability

Part-time

Preferred Environment

Git, JavaScript, Cypress, Appium, Selenium, Playwright, Java, Python, GitHub, Jenkins Pipeline

The most amazing...

...project I've tackled: From startups to giants like Adobe, I've swiftly set up QA, automation, and CI, unearthing bugs early and ensuring quality across domains.

Work Experience

Developer Screener

2021 - PRESENT
Toptal
  • Started my role as a junior screener and was able to quickly establish myself as one of the top three screeners on the team.
  • Ranked consistently in the top three as the success rate is measured by talent review.
  • Provided my services as a screener for Toptal. Became a part of the Toptal network and consider it a significant accomplishment.
Technologies: JavaScript, Python, Manual QA, QA Testing, UI Automation, REST API Automation, Selenium, Cypress, Playwright, Pytest, TestNG, Page Object Model (POM), Appium, CI/CD Pipelines, Docker, Automated Testing, Software QA, Test Automation Frameworks, Browser Automation, Puppeteer, Scraping, JSON, Test Data, Integration Testing, Test Engineering, GitHub Actions, Mobile App Testing, Mobile Device QA Automation, Testsigma, Web App Testing, Documentation, Amazon Web Services (AWS), Flutter, iOS, Mobile, User Interface (UI), APIs, Web Applications, Artificial Intelligence (AI)

Automation Infrastructure Engineer

2019 - PRESENT
Adobe
  • Acted as an automation engineer, Created a scalable and reliable SOAP API framework with all the mock services needed for proper end-to-end testing.
  • Worked on best practices documentation and implemented effective QA practices that caught bugs early and reduced stress. Created clear and concise documentation to help team members get up to speed quickly and work independently.
  • Created various Jenkins jobs, including provisioning different server configurations and running different types of tests, as well as Smoke, Sanity, Nightly, and validation jobs that execute all tests and test groups.
  • Developed a PR validation job triggered every time a developer commits code. This job significantly increased the reliability and confidence of developers in merging PRs.
Technologies: Docker, CI/CD Pipelines, API Testing, Automated Testing, Software QA, Regression Testing, Smoke Testing, Test Automation Frameworks, Test Planning, Scrum, Test-driven Development (TDD), Browser Automation, E2E Testing, Functional Testing, Testing Strategy, PostgreSQL, Test Data, Integration Testing, Unit Testing, Test Engineering, GitHub Actions, Test Cases, Test Scripting, Web App Testing, Documentation, Amazon Web Services (AWS), Firebase, Flutter, User Interface (UI), APIs, Web Applications, Microservices, Distributed Systems, Cloud Services

QA Automation Engineer

2024 - 2024
Imfiy BV
  • Assessed and restored the existing automation framework; redesigned it incrementally for enhanced stability and scalability.
  • Upgraded the infrastructure to support development and automation; implemented CI pipelines and workflows for seamless integration.
  • Optimized automation processes, significantly boosting product quality and development efficiency.
Technologies: Java, TestNG, CI/CD Pipelines, QA Automation, TypeScript, GitHub, Playwright, Quality Assurance (QA), API Testing, UI Testing, Jenkins, GitLab CI/CD, GitHub Actions, DevOps, Agile, Docker, User Interface (UI), APIs, Web Applications, Microservices, Cloud Services, TestRail

QA Engineer

2023 - 2024
Yara
  • Initiated automation from scratch, achieving 30% coverage within six months.
  • Produced stable, flaky, test-free automation. Utilized API for setting up data prerequisite.
  • Integrated CI, leading to early bug detection. Implemented the Nigtly job, release validation job, and PR validation job.
  • Managed Jira bugs efficiently to achieve optimal issue resolution.
  • Crafted effective test cases through deep project understanding, based on which automation was so effective.
Technologies: Quality Assurance (QA), QA Automation, Test Automation, Appium, Functional Testing, Non-functional Testing, Cucumber, Selenium, Playwright, API Testing, Automated Testing, GitHub Actions, Software QA, Regression Testing, Smoke Testing, Test Automation Frameworks, Test Planning, Scrum, Browser Automation, E2E Testing, UI Testing, QA Test Plan Management, BrowserStack, JSON, Test Data, Integration Testing, Test Engineering, Mobile Apps, CI/CD Pipelines, Mobile App Testing, Test Cases, Test Scripting, Web App Testing, Documentation, Amazon Web Services (AWS), Firebase, Flutter, iOS, Mobile, User Interface (UI), APIs, Web Applications, Microservices, Databases, Cloud Services, TestRail

SDET

2019 - 2019
PitchStone Technology, LLC
  • Established QA processes and increased test coverage for UI and API by 70%.
  • Adapted and wrote proper documentation to facilitate the transition despite the project's unfamiliar set up, which used Groovy and Spock.
  • Refactored existing automation and delivered results beyond the team's expectations, earning their satisfaction and trust during my six-month tenure.
Technologies: Quality Assurance (QA), Selenium, QA Automation, QA Testing, Groovy, GEB, Spock, API Testing, Automated Testing, Software QA, Regression Testing, Smoke Testing, Test Automation Frameworks, Test Planning, Scrum, Browser Automation, UI Testing, Functional Testing, QA Test Plan Management, JSON, PostgreSQL, Test Data, Test Engineering, Mobile App Testing, Test Cases, Test Scripting, Web App Testing, Documentation, Amazon Web Services (AWS), Flutter, User Interface (UI), APIs, Web Applications, Microservices, Cloud Services, TestRail

Automation QA Lead

2017 - 2019
InsideMaps
  • Planned and controlled the testing process for visual property representation software.
  • Created automation frameworks for web and mobile applications.
  • Implemented continuous integration where every commit server build was run, after that automation suite executed and an adequate report sent over email.
  • Accepted and clarified project requirements. Checked if the current project requirements are met and all test cases are covered.
  • Planned and organized all the QA team activities. Organized quality training sessions for junior team members. Supervised team members.
Technologies: Fastlane, QA Automation, GitHub, REST Assured, Apache Maven, Sikuli, Appium, Selenium, TestNG, API Testing, Automated Testing, Software QA, Regression Testing, Smoke Testing, Test Automation Frameworks, Test Planning, Scrum, Browser Automation, E2E Testing, UI Testing, Functional Testing, QA Test Plan Management, QA Leadership, JSON, PostgreSQL, Test Data, Integration Testing, Test Engineering, Mobile Apps, CI/CD Pipelines, Mobile App Testing, Mobile Device QA Automation, Test Cases, Test Scripting, Web App Testing, Documentation, Amazon Web Services (AWS), iOS, Mobile, User Interface (UI), APIs, Web Applications, Microservices, Databases, Cloud Services, TestRail

Automation Tester

2016 - 2017
Endava - MTT
  • Planned, wrote, and maintained automated and manual tests for mobile app messaging platform in the airline industry.
  • Created a test suite in Practitest and performed manual testing for SaaS, web application, iOS, and Android application.
  • Wrote and maintained automation test scripts using Groovy and Cucumber/Gherkin.
  • Worked as a part of Scrum team where I participated and was constantly involved in all scrum meetings and procedures.
  • Collaborated constantly with development and product management in order to prioritize and increase test coverage.
Technologies: QA Automation, Gherkin, Postman, Kibana, Selenium, Cucumber, Groovy, Automated Testing, Software QA, Regression Testing, Smoke Testing, Test Automation Frameworks, Test Planning, Scrum, Browser Automation, E2E Testing, UI Testing, Functional Testing, QA Test Plan Management, JSON, PostgreSQL, Test Data, Integration Testing, Test Engineering, Mobile Apps, Mobile App Testing, Test Cases, Test Scripting, Web App Testing, Documentation, Amazon Web Services (AWS), iOS, Mobile, User Interface (UI), APIs, Web Applications, Cloud Services

Scrum Master | Automation Tester

2015 - 2016
Endava - Cisco Webex Conferencing Software
  • Worked on automating tests and was a scrum master for video and web conferencing software.
  • Facilitated daily scrum, sprint planning, and sprint demo.
  • Helped the team or individual to clarify goals and actions to achieve them.
  • Shielded the team from outside distractions and interferences.
  • Contributed to removing team and personal impediments.
Technologies: QA Automation, Sikuli, Selenium, TestNG, Automated Testing, Software QA, Regression Testing, Smoke Testing, Test Automation Frameworks, Test Planning, Scrum, Browser Automation, E2E Testing, UI Testing, Functional Testing, QA Test Plan Management, PostgreSQL, Test Data, Test Engineering, Mobile Apps, Test Cases, Web App Testing, Documentation, User Interface (UI), APIs, Web Applications

Automation Tester

2014 - 2015
Endava - Cisco Webex Conferencing Software
  • Conducted manual and automated testing for Cisco video and web conferencing software.
  • Actively involved in planning and evaluating user stories.
  • Wrote automation test scripts using Java and Testng.
  • Reported and reproduced issues and emphasized critical bugs.
  • Conducted manual and automated testing. Wrote and maintained test suites.
Technologies: QA Automation, Selenium, TestNG, Automated Testing, Software QA, Regression Testing, Smoke Testing, Test Automation Frameworks, Test Planning, Scrum, Browser Automation, E2E Testing, Functional Testing, PostgreSQL, Test Data, Test Engineering, Test Cases, Web App Testing, Documentation, User Interface (UI), APIs, Web Applications

Sustaining Manual Tester

2012 - 2014
Endava - Cisco CICP Client
  • Manually tested highly complex CISCO CICP voice client software.
  • Manually tested Jabber, CUCIMOC, and CUCILync voice and chat software.
  • Executed manual tests, configured test beds, sought and reported defects, and monitored the defect lifecycle.
  • Implemented and managed a highly complex local test Cisco lab infrastructure for testing and for development. (VMware, AD, Microsoft Lync, Microsoft server 2008).
  • Ensured that the documentation was in order and up to date with the product.
Technologies: Microsoft Servers, Microsoft Lync, Microsoft, VMware, Cisco Jabber, Cisco, Manual Testing, Software QA, Regression Testing, Smoke Testing, Test Planning, Scrum, E2E Testing, Functional Testing, Test Data, Test Engineering, Test Cases, Documentation, User Interface (UI), APIs, Web Applications

Experience

Insidemaps

For this project, I have organized the QA from the beginning, where I created automated functional and API test suites and integrated them with Jenkins CI to maintain the quality of the app at high levels at all times and the testing scope consisted of a web application, a mobile application, and a public API.

For the web application, I've created a complex but scalable and manageable framework that combines Selenium and Sikuli automation tools. The biggest challenge was to verify images on remote machines. Also, the challenge was to implement a system that mimics the behavior of a mobile app upload images system to AWS s3.

For the mobile application, I've used Appium and set it up on an actual device. The biggest challenge was setting up Fastlane for CI and ensuring that real device configuration maintained functionality after updates.

Jenkins was used for continuous integration. After every development commit, a build server job was triggered, and adequate automation jobs after. In the end, a mail was sent to all parties of interest with automation report information.

Automate 3D Tour

The 3D virtual tour is a visual representation of property indoor space on a web page.

To automate 3D tour, I needed to create a framework that uses Selenium for web page interaction and Sikuli for image comparison and 3D tour navigation. The biggest challenge was to create a Sikuli server on a remote machine that accepts and processes requests, compares images using Sikuli, and returns a result.

MTT

For this project, I worked as a remote engineer in an agile environment.

Main responsibilities were to attend sprint-planning sessions, attend daily stand-ups, arrange meetings with developers for short hand-off demonstrations, attend sprint retrospectives, document test cases, organize testing so I can test throughout the sprint, manually execute tests, write reports, document issues, automate new features and maintain old scripts.

Testing was done on mobile apps (Android, iOS), web applications (cross-browser) along with back-end testing.

Automation was written for testing API and web application using Cucumber and Groovy.

Tools used were Postman, Charles, Pusher, Kibana. For continuous integration, Jenkins was used.

Cisco Webex

For this project, testing was done for proprietary conferencing system running on-premise.

Adequate knowledge in networking protocols, voice protocols, VMware and virtualization, LDAP, SSO, certificates, basic web security, DNS, DHCP, and also working on Cisco hardware infrastructure was needed.

Main responsibilities were to check new features functionalities and execute regression suites, provide immediate feedback if features are not working correctly, configuring test beds, finding and reporting defects, and monitoring the defect lifecycle.

Tools used were Wireshark, fiddler, burp, Sipp, Postman.
For automation Selenium, AutoIt, Sikuli, Testng, and Ant.

Cisco Jebber

For this project, manual testing was done for proprietary voice and chat desktop application running on-premise.

It required the knowledge of networking protocols, voice protocols, VMware and virtualization, LDAP, SSO, Certificates, DNS, DHCP and also working on Cisco hardware infrastructure.

Testing was done on Windows and Mac desktop apps. Main responsibilities were to execute manual tests, configuring test beds, finding and reporting defects, and monitoring the defect lifecycle.

Debugging tools used were Wireshark and Sipp.

Education

2003 - 2009

Bachelor's Degree in Computer Science

College of Electrical Engineering - Belgrade, Serbia

Certifications

MAY 2015 - PRESENT

Scrum Master

Agile Serbia

MAY 2012 - MAY 2015

CCNA

Cisco

Skills

Libraries/APIs

Playwright, Selenium Grid, Sikuli, Jenkins Pipeline, Puppeteer

Tools

REST Assured, Cucumber, Jenkins, GitHub, Git, GitLab CI/CD, TestRail, Fastlane, Jira, Cisco Jabber, VMware, Microsoft Lync, Postman, Kibana, Apache Maven, SikuliX, Pytest, BrowserStack

Languages

JavaScript, Python, Java 8, TypeScript, Gherkin, Groovy, Java

Frameworks

TestNG, Selenium, Cypress, Appium, Flutter, GEB, Spock

Paradigms

Agile, Test Automation, Manual Testing, Testing, Page Object Model (POM), Functional Testing, Automated Testing, Scrum, E2E Testing, Unit Testing, Microservices, DevOps, Non-functional Testing, Test-driven Development (TDD)

Platforms

iOS, Testsigma, Amazon Web Services (AWS), Mobile, Android, Windows, MacOS, Microsoft, Docker, Linux, TestLink, Firebase

Storage

JSON, PostgreSQL, Databases

Other

Mobile App Testing, CI/CD Pipelines, Networks, QA Automation, Quality Assurance (QA), Selenium Page Object, Manual QA, Manual Software Testing, UI Automation, API Testing, GitHub Actions, Software QA, Regression Testing, Smoke Testing, Test Automation Frameworks, Test Planning, Browser Automation, UI Testing, QA Test Plan Management, Test Data, Integration Testing, Test Engineering, Mobile Apps, Mobile Device QA Automation, Test Cases, Test Scripting, Web App Testing, Documentation, User Interface (UI), APIs, Web Applications, Distributed Systems, Cloud Services, Artificial Intelligence (AI), QA Leadership, Cisco, Microsoft Servers, QA Testing, REST API Automation, Scraping, Testing Strategy, Geolocation, Maps, Logistics

Collaboration That Works

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