The Top Agile Developer Interview Questions and Answers

Landing a job as an agile developer requires strong technical skills and expertise with agile methodologies. During the interview process, hiring managers will ask targeted questions to assess your qualifications. I’ve compiled some of the most common agile developer interview questions with sample answers to help you ace your next interview.

What is Agile Development?

Agile development refers to a set of principles and practices that emphasize iterative development collaboration, adaptability and delivering working software frequently. Some key aspects of agile development include

• Breaking projects into small, iterative cycles called sprints
• Daily standup meetings to communicate status and blockers
• Focus on working software over comprehensive documentation
• Welcoming changing requirements even late in development
• Close collaboration between developers, QA, and business stakeholders
• Retrospectives after each sprint to reflect and improve

Popular agile frameworks like Scrum, Kanban, and Extreme Programming embody these principles Agile provides greater transparency, continuous feedback, and ability to adapt compared to traditional waterfall development

Explain What a Release Burndown Chart Is

A release burndown chart tracks the completion of scope for a product release over sprints. It shows the remaining story points or efforts for features that must be completed for the release to be done. The X-axis represents time in sprints, while the Y-axis depicts remaining scope as story points or ideal hours.

A release burndown gives the team visibility into release progress. If the burndown line trends down towards zero, the team is on track to complete the release on time. An upward trend means the release is at risk of not being completed as planned. Teams can use this data to take corrective actions like removing or descoping features.

Explain What a Defect Burndown Chart Is

A defect burndown chart visualizes the open defects from testing over time. The X-axis shows time, often in days of testing or sprints. The Y-axis depicts the total open defects. As testing progresses and developers fix bugs, the burndown line trends down towards zero open defects.

A defect burndown communicates testing progress and defect resolution rates. An upward trend may indicate new defects are being found faster than developers can fix them. The team can then take actions like allocating more developers to bug fixing. The chart also helps forecast the end of the testing cycle.

Define the Term “Build Breaker” in Agile Development

A build breaker refers to a defect that blocks the team from creating a viable build of the software. For example, defects that crash the application on startup, cause data corruption, or prevent major features from working are considered build breakers. These showstopper bugs block other testing activities.

In agile methodologies, teams strive to create potentially shippable product increments each sprint. Build breakers prevent this goal by stopping the team from having a runnable build. So fixing build breakers becomes the team’s top priority in order to unblock further development and testing.

Explain What Pair Programming Means

Pair programming is an agile practice where two developers work together at one workstation. One developer acts as the driver, writing code, while the other developer observes, reviews, and offers suggestions as the navigator. The two programmers switch roles frequently.

Pair programming enables continuous code reviews, sharing of knowledge, and better defect prevention. Having two minds tackle problems together can also produce higher quality solutions. Some other benefits include:

• Mentoring junior developers
• Reducing bus factor risks
• Keeping the team focused and motivated
• Promoting collective code ownership

However, pair programming reduces developer productivity as two people work on one task. Teams must balance its benefits against the capacity loss. Pair programming works best for complex tasks, teaching moments, and spikes.

Explain What a Sprint Retrospective Meeting Is

A sprint retrospective is a meeting held by agile teams at the end of each sprint to reflect on what went well, what can be improved, and how to implement those improvements. The scrum master facilitates the discussion, often using techniques like:

• Gathering lessons learned and feedback from the team
• Celebrating wins and progress
• Analyzing root causes of issues
• Prioritizing action items to improve in the next sprint

Retrospectives enable continuous process improvement. They give teams a regular forum to identify what parts of the process are working versus problematic. The outcome is a set of improvements the team will enact in the next sprint.

What Are the Benefits of Test Driven Development?

Test driven development (TDD) is a practice where developers first write automated tests that define code requirements before writing functional code. TDD offers several key benefits:

• Forces developers to think through requirements upfront
• Catches defects early in development cycles
• Results in higher test coverage and quality
• Reduces time spent debugging
• Encourages modular, flexible code design
• Gives confidence for refactoring

The TDD workflow is red-green-refactor: write a failing test, quickly make it pass, then refactor. This rapid feedback loop helps developers maintain focus and progress. TDD does have a learning curve and may seem slower at first. But the long term time savings from preventing bugs outweigh initial costs.

How Do You Prioritize User Stories in Agile?

Teams use various techniques to prioritize user stories:

Business value – High value features that offer ROI should be prioritized first. Value can be weighted by factors like revenue potential, customer requests, competitive advantage, and risk reduction.

Dependencies – Stories that have dependencies on other stories should be sequenced logically. Highly dependent stories should be grouped in sprints.

Risks – Riskier stories should be built earlier to validate assumptions and prevent downstream surprises. Unknowns should be tackled upfront.

Size – Larger stories should be broken down so a mix of short and long stories are included in each sprint.

Technical debt – Some sprints should focus on addressing accumulating technical debt through refactoring, infrastructure changes, etc.

No single factor determines priority. Product owners balance these aspects based on the team, project, and objectives. Priorities can change so constant re-evaluation occurs.

How Do You Estimate User Stories in Agile?

Teams use various techniques to estimate the level of effort for user stories:

Story points – Stories are ranked in terms of relative complexity on a scale like 1, 2, 5, 8, etc. Points don’t directly equal time – they represent complexity judgments.

T-shirt sizing – Stories are categorized into T-shirt sizes like XS, S, M, L, XL to denote level of effort.

Ideal days – Stories are estimated in the amount of ideal programming days required to complete them. Ideal days remove inefficiencies.

Planning poker – The team plays cards face down representing story points or days for each story, then reveals them simultaneously to arrive at a consensus estimate.

Comparative – Stories are sized relative to other stories the team is familiar with: larger, smaller, about the same as X story.

Estimates should come from the development team doing the actual work. Estimates get more accurate over time as the team’s velocity is established.

How Do You Manage Technical Debt in Agile?

Here are some strategies for managing technical debt in agile:

• Quantify debt into story points so it can be prioritized alongside new features
• Allocate sprints focused solely on paying down debt through refactoring, upgrades, etc.
• Build slack time into sprints to handle some refactoring
• Prioritize architectural changes and fixes that reduce velocity
• Include technical stories like performance improvements in each sprint
• Automate testing to enable large scale refactoring
• Leverage spike stories to investigate solutions for major debt items

Technical debt should be tracked, communicated, and assigned like any other requirement. Left unchecked, it will accumulate and drag down team productivity. Paying down debt in small increments prevents it from crushing the team.

How Does Agile Testing Differ from Traditional Testing?

Agile testing leverages different techniques compared to traditional waterfall testing:

• Testing is interleaved throughout development in agile rather than at the end
• Short iterative test cycles rather than long marathon cycles
• Focus on business facing tests and end user scenarios
• Rely on extensive automation versus manual testing
• Testing against user stories versus detailed requirements
• Visual tracking of testing progress like burn down charts
• Whole team responsibility for quality versus just QA’s job

Agile testing is driven by delivering business value and rapid feedback. It requires testers to become more integrated with programmers and product owners. Testing progresses incrementally across sprints rather than trying to cover everything in final user acceptance testing.

How Do You Coordinate Code Deployments in Agile?

Code deployments can be coordinated in agile through techniques like:

• Maintaining a shared branch like dev, staging, master with modeled production environments
• Automating builds and deployments using CI/CD pipelines
• Leveraging feature flags to control rollout of new features
• Using canary or incremental rollout to reduce risk
• Running regression test suites with each deployment
• Monitoring key metrics post-deployment to detect issues
• Making deployments and rollbacks during business hours