These questions are based on real interview experiences from candidates who interviewed at this company. You can practice answering them interactively on Dataford to better prepare for your interview.

Preparation for Glean is distinct because the company values strong Computer Science fundamentals even for Quality Assurance roles. You should approach this not just as a testing interview, but as an engineering interview with a focus on quality.

Core Computer Science Fundamentals – Glean places a heavy emphasis on your understanding of how software works under the hood. You will be evaluated on your grasp of Operating Systems, DBMS, and Object-Oriented Programming (OOP). Interviewers want to know that you understand the systems you are testing, not just the user interface.

Test Strategy & Architecture – You must demonstrate the ability to break down complex systems. Expect to analyze web applications and APIs, dissecting them into testable components. You will be judged on your ability to identify edge cases, security vulnerabilities, and performance bottlenecks in a structured manner.

Problem Solving & DSA – Unlike many QA interviews that focus solely on testing theory, Glean includes Data Structures and Algorithms (DSA) in their screening. You need to be comfortable writing code to solve logic problems, proving that you have the technical capability to write sophisticated automation scripts.

Communication & Culture – You may interview with founding team members or senior engineers. They look for candidates who can articulate technical concepts clearly and who show a proactive, "owner" mindset. Being able to explain the why behind your testing approach is just as important as the how.

The interview process at Glean is rigorous and designed to filter for candidates with strong technical depth. Based on recent candidate experiences, the process can move relatively quickly, sometimes condensing multiple rounds into a few days, though the timeline can vary depending on the recruitment channel.

You should expect a multi-stage process that begins with a screening round—often with a recruiter or a member of the developer productivity team—to assess your background and technical fit. If you pass the screen, you will move into a series of technical rounds. These are not purely behavioral; they are hands-on and technical. You will face questions on CS fundamentals (OS, OOP, DBMS) and coding challenges similar to what a software developer might encounter, adjusted for the QA context. Subsequent rounds will dive deeper into practical testing scenarios, such as breaking down a website’s functionality or designing an API test plan.

The final stages typically involve managerial or behavioral interviews to assess culture fit. Note that the bar is high; the team is known to be selective, looking for objective proof of skills. Communication regarding results can sometimes be brief, so it is important to perform strongly and clearly in every interaction to leave no doubt about your qualifications.

The visual timeline above outlines the typical progression from application to final decision. Use this to structure your study plan: devote the early days to refreshing CS fundamentals and coding basics, and as you progress, shift your focus to system breakdown and test strategy. Be prepared for a high-intensity loop, especially if you are scheduled for back-to-back technical rounds.

To succeed at Glean, you must demonstrate competency across several distinct technical areas. The interviewers are looking for a blend of theoretical knowledge and practical application.

Computer Science Fundamentals

This is a differentiator in Glean’s process. You cannot rely solely on testing experience; you must have a grip on the building blocks of software.

• Why it matters: To test complex AI and search infrastructure, you need to understand how data is stored, processed, and retrieved.
• What strong performance looks like: You can confidently explain concepts like process management, memory handling, SQL normalization, and inheritance/polymorphism without hesitation.

Be ready to go over:

• Operating Systems – Concepts like deadlocks, paging, threading, and process scheduling.
• DBMS – SQL queries, ACID properties, indexing, and normalization forms.
• OOP Concepts – Encapsulation, abstraction, polymorphism, and inheritance, applied in languages like Java or Python.
• Advanced concepts – Basic networking protocols (HTTP/HTTPS, TCP/IP) and how they impact web application performance.

Example questions or scenarios:

• "Explain the difference between a process and a thread. How does this impact testing a multi-threaded application?"
• "Write a SQL query to find the second highest salary from a table."
• "How would you apply polymorphism in a test automation framework?"

Data Structures & Algorithms (DSA)

You will face coding questions. While they may not be as intense as a core SDE role, they are significant hurdles.

• Why it matters: Automation requires coding. Glean needs engineers who can write efficient, maintainable scripts.
• What strong performance looks like: You can write clean, working code for array, string, or list manipulation problems and explain the time complexity (Big O).

Be ready to go over:

• Arrays & Strings – Manipulation, searching, and sorting.
• Hash Maps – Using key-value pairs for frequency counting or lookups.
• Basic Logic – Iteration, recursion, and conditional logic.

Example questions or scenarios:

• "Given a string, find the first non-repeating character."
• "Reverse an array without using a temporary array."
• "Check if two strings are anagrams of each other."

System Breakdown & Test Planning

This area tests your product intuition and QA mindset.

• Why it matters: You need to identify where a system is likely to break before it actually does.
• What strong performance looks like: You take a systematic approach—starting from high-level user flows and drilling down into API validation, database integrity, and edge cases.

Be ready to go over:

• Web Architecture – Understanding the client-server model, APIs, and frontend rendering.
• Test Scenarios – Functional, non-functional, security, and performance testing.
• API Testing – Verifying response codes, payloads, and latency.

Example questions or scenarios:

• "Here is a login page. Break down every possible test case, including security and edge cases."
• "How would you test the search functionality of an e-commerce website?"
• "Verify an API endpoint that uploads a file. what are the negative test cases?"

The word cloud above highlights the frequency of topics reported by candidates. Notice the prominence of CS Fundamentals, OOP, and DBMS alongside standard testing terms. This confirms that your preparation should be heavily weighted towards "engineering basics" rather than just manual testing methodologies.