Thilan Dissanayaka Interview Guides Jan 05

CI/CD concepts - Interview preparation guide

What is CI/CD?

CI/CD stands for Continuous Integration and Continuous Delivery/Deployment.

CI is the practice of automatically integrating code changes from multiple contributors into a shared repository, often multiple times a day, and running automated tests to detect issues early.

CD refers to two related practices:

Continuous Delivery: Automatically preparing code changes for release to production.

Continuous Deployment: Automatically deploying every code change to production without manual intervention.

What are the key benefits of CI/CD?

  • Faster release cycles

  • Early detection of bugs

  • Improved code quality

  • Reduced integration issues

  • Consistent deployment process

  • Better collaboration between development and operations

What tools are commonly used for CI/CD?

  • CI Tools: Jenkins, GitHub Actions, GitLab CI, CircleCI, Travis CI, Bamboo

  • CD Tools: Spinnaker, Argo CD, Flux

  • Supporting tools: Docker, Kubernetes, Terraform, Ansible, Helm

What is the difference between Continuous Delivery and Continuous Deployment?

  • Continuous Delivery prepares code for production release but requires manual approval to deploy.
  • Continuous Deployment automatically deploys code to production without manual steps.

What is a pipeline in CI/CD?

A pipeline is a set of automated steps that code goes through from commit to deployment. It typically includes stages like:

  • Code checkout
  • Build
  • Test
  • Package
  • Deploy

How do you handle secrets and sensitive data in CI/CD pipelines?

  • Use secret management tools like HashiCorp Vault, AWS Secrets Manager, or GitHub/GitLab secrets.
  • Avoid hardcoding secrets in scripts or code.
  • Use environment variables securely provided by the CI/CD platform.

What is the role of containers in CI/CD?

Containers (e.g., Docker) ensure that applications run in consistent environments across development, testing, and production. They help:

  • Speed up build and deployment
  • Simplify dependency management
  • Improve scalability and isolation

How do you ensure quality and security in a CI/CD pipeline?

  • Add unit, integration, and end-to-end tests
  • Include linting and static code analysis
  • Use security scanners (e.g., Snyk, Trivy, SonarQube)
  • Conduct vulnerability checks for dependencies and containers -Apply approval workflows for production deployments

What are some challenges you’ve faced in implementing CI/CD?

  • Long pipeline execution times
  • Flaky tests slowing down deployment
  • Environment mismatches between dev and prod
  • Managing secrets and credentials securely
  • Resistance to cultural change within teams

How would you implement a rollback strategy in a CI/CD pipeline?

  • Maintain previous builds/artifacts for quick redeployment
  • Use blue-green deployments or canary releases
  • Automate rollback steps in case of failed health checks
  • Monitor production health post-deployment and trigger rollback on anomalies

What is Infrastructure as Code (IaC) and how does it relate to CI/CD?

IaC is managing and provisioning infrastructure using code and automation tools like Terraform, CloudFormation, or Ansible. In CI/CD, IaC ensures:

  • Consistent environments
  • Version-controlled infrastructures
  • Easy automation of infrastructures
ALSO READ
Error based SQL Injection
Apr 26 Application Security

In the previous example, we saw how a classic [SQL Injection Login Bypass](https://hacksland.net/sql-injection-login-bypass) works. SQL Injection is not all about that. The real fun is we can extract....

Basic concepts of Cryptography
May 03 Cryptography

Cryptography is the practice of securing communication in the presence of third parties. It's a cornerstone of digital security, allowing us to protect sensitive information even when it's sent....

Penetration Testing - Interview preparation guide
Jan 06 Interview Guides

# Fundamentals of Penetration Testing ## What is penetration testing? Penetration testing, or ethical hacking, involves simulating cyberattacks on systems, networks, or applications to identify....

Singleton Pattern explained simply
Apr 26 Software Architecture

Ever needed just one instance of a class in your application? Maybe a logger, a database connection, or a configuration manager? This is where the Singleton Pattern comes in — one of the simplest....

Kafka - Interview preparation guide
Jan 28 Interview Guides

## What is Apache Kafka? Apache Kafka is a distributed event streaming platform designed for high-throughput, fault-tolerant, and real-time data streaming. It is used for building real-time data....

Docker - Interview preparation guide
May 08 Interview Guides

## What is Docker and why is it used? Docker is a platform for developing, shipping, and running applications in containers. Containers package an application with its dependencies, ensuring....