About VWO VWO is a leading Digital Experience Optimization platform trusted by over 3,000 businesses in 100+ countries, including global brands like Samsung, Vodafone, Toyota, HBO, and Domino's. What began 15 years ago as one of the world’s first A/B testing tools has since evolved into a comprehensive, enterprise-grade platform used by product, marketing, and growth teams to experiment, personalize, analyze behavior, and build exceptional digital experiences. Today, VWO offers a full-stack suite for A/B testing, multivariate testing, feature rollouts, heatmaps, session recordings, behavioural analytics, surveys, personalization, and more across web, mobile, and server-side applications — all in one unified platform. We enable teams to make confident, data-driven decisions that drive user engagement, retention, and conversion. VWO is a profitable, founder-led business with $50M+ ARR, strong EBITDA margins, and a history of capital-efficient, sustainable growth. In January 2025, Everstone Capital acquired a majority stake in the company to help accelerate our global expansion — both organically and inorganically. We are a fully remote team of 450+ people, with go-to-market teams across the Americas, Europe, and APAC, and product and engineering anchored in India. Our culture values deep thinking, fast execution, and strong ownership — with minimal bureaucracy and high autonomy. Despite our scale, we continue to operate with the agility and ambition of a startup. As a Lead JavaScript Engineer , you will be required to work on various JavaScript libraries that are served on our customers’ websites thereby impacting millions of users. These libraries are the core of all the features of VWO. We love vanilla JavaScript and work with cutting-edge technologies like TypeScript, Rollup.js, Cypress, ESLint. We are obsessed with Web Performance. See some of the improvements that we did https://engineering.wingify.com/posts/performance-improvements-in-vwo-smart-code/ Job Responsibilities: Development of Core JavaScript libraries. Writing reusable code or modules that can be used across all the JavaScript libraries. Talking about your work - we love open source software, we heavily use them, and talking about how we use them is the least we can do to help the community. See our engineering blog and our GitHub page Skills & Experience:- 6-8 Years of Experience Passion for writing Vanilla JavaScript Strong knowledge and experience in JavaScript, HTML, CSS. Work Experience with TypeScript Deep understanding of the DOM, Browser Events, JavaScript APIs, Canvas rendering, etc. Deep understanding of how the browsers work. Regard for optimizations that focus to deliver content to the user as quickly as possible. Awesome Debugging Skills. Passion to write automated tests to verify the working of libraries (You can’t possibly verify things on all devices and on all browsers manually). We use Cypress for this. Understanding the similarities and differences across browsers (young and old). Experience in writing modular JavaScript code Knowledge of high-level programming concepts like promises, data-binding. Passion to stay up to date with the constantly evolving world of front-end development. Show more Show less

About VWO VWO is a leading Digital Experience Optimization platform trusted by over 3,000 businesses in 100+ countries, including global brands like Samsung, Vodafone, Toyota, HBO, and Domino's. What began 15 years ago as one of the world’s first A/B testing tools has since evolved into a comprehensive, enterprise-grade platform used by product, marketing, and growth teams to experiment, personalize, analyze behavior, and build exceptional digital experiences. Today, VWO offers a full-stack suite for A/B testing, multivariate testing, feature rollouts, heatmaps, session recordings, behavioural analytics, surveys, personalization, and more across web, mobile, and server-side applications — all in one unified platform. We enable teams to make confident, data-driven decisions that drive user engagement, retention, and conversion. VWO is a profitable, founder-led business with $50M+ ARR, strong EBITDA margins, and a history of capital-efficient, sustainable growth. In January 2025, Everstone Capital acquired a majority stake in the company to help accelerate our global expansion — both organically and inorganically. We are a fully remote team of 450+ people, with go-to-market teams across the Americas, Europe, and APAC, and product and engineering anchored in India. Our culture values deep thinking, fast execution, and strong ownership — with minimal bureaucracy and high autonomy. Despite our scale, we continue to operate with the agility and ambition of a startup. Job Description: As a Senior Engineer - QA , you will be working on our Product VWO (https://vwo.com), all our products which include our customer-facing application, JavaScript library, and Mobile SDK. We work iteratively and ship code often, and are looking for people who can constantly monitor the state of our application from a quality perspective. You will be responsible for ensuring the high quality of our products that are used by over 2500+ customers across 90+ countries. Your responsibilities: Ensure that our products are awesome and of high quality. Confirm, verify bugs, and determine steps to reproduce. Design and implementation of internal automation tools for QA. Building front end, UI, API, load, performance, and UAT test suites for our applications. Work closely with Product, Marketing, and Development Teams on projects to understand requirements and create, automate, execute, manage, and report test plans, test cases, and test reports. Own QA activities for the scrum team and drive scoping, planning, executing, monitoring & controlling test activities. Be the first point of contact for all client issues, debug them, and get them resolved in time for a better customer experience. Understand deployment scenarios and manage deployment to test environments. Drive the adoption of best practices in testing and maintainability with the organization. Talking about your work - we love open source software, and heavily use them, and talking about how we use them is the least we can do to help the community. See our engineering blog. Requirements: Min 3 to 6 yrs years of experience in manual and automation testing. Analytical ability to understand and work with complex application architecture. Well-versed in Functional Automation - Web/Mobile and API. Knowledge of API testing and automation with Rest Assured. Proficient in any of the following Automation Tools - Selenium / Protractor. Experience in Performance/load testing with tools like Jmeter is a bonus. Knowledge of GenAI Applications and hands-on experience in its usage will be considered a major advantage In-depth knowledge of programming languages: Java and JavaScript. Hands-on knowledge of testing backend platforms - Databases, Cache, and Queues. Knowledge in client-side debugging for RCA of bugs. Experience in creating and maintaining QA infra - Selenium Grid and Docker. Experience in Version control tools like Git. And CI tools like Jenkins are required. Keen inclination towards usability and end-user perspective of the application we build. Own QA Processes in scrums. Estimate and plan projects with accuracy. Contribution to open-source projects related to QA is a strong plus. Works independently under minimal direction with strong work ethics. Location : Remote (Wingify is a remote-first company) Show more Show less