Whether using as a Platform-as-a-Service, such as Docker, or orchestration through a tool like Kubernetes, the race is on for containerized solutions. In October 2021, the General Services Administration released its Containerization Readiness Guide. Containerized software solutions allow agencies to develop applications rapidly, scale quickly and optimize compute resources. The need is especially pressing for legacy applications which must also remain secure as they modernize. 

Creating Dockerfiles for Containerization

When we think of containerization, the first step is to create a Dockerfile for each application. While the Dockerfile provides flexibility to build an image that is only limited by your ability to script, it also adds overhead on developers to ensure the accuracy, efficiency and security of these images. For example, the developers must ensure that the Dockerfiles are as small as possible by removing any redundant dependencies that can increase the image size, which increases the build time. They must also confirm the files don’t contain any secrets or config keys. Additionally, they should verify that the base image comes from a secure source while actively scanning the images for new security vulnerabilities. If the image contains vulnerabilities that can spread to all containers that use the vulnerable image. Without proper planning and oversight, things can quickly get messy.

Benefits of using Buildpacks over Dockerfiles

Buildpacks allow you to convert application code into a secure, efficient and production ready container image without the need to create a Dockerfile for each application. It examines applications written in Java, .NET, Python and many other languages to determine all the dependencies it needs and then configures them appropriately to run on any cloud. Buildpacks also offer the capability to swap out OS layers without rebuilding an image. This reduces build time by eliminating the need to recreate all the layers when the base image is updated.

Using Tekton for creating CI Pipelines 

Tekton is a cloud-native solution for building CI/CD pipelines. Unlike Jenkins, Tekton was designed to work natively on Kubernetes and incorporates AWS EKS best practices by default. It installs and runs as an extension on a Kubernetes cluster and provides a set of open source Kubernetes resources to build and run CI/CD pipelines, such as parameterized tasks and pipelines. Just like Jenkins uses plugins to extend its capabilities, Tekton has Tekton Hub – a catalog of predefined tasks, you can create custom tasks and scripts to extend the capabilities of these tasks if you can’t find a task that precisely matches your requirements. Tekton’s modularity allows for componentization, standardization and reusability within the CI/CD workflow. Buildpacks project provides tasks that Tekton can leverage to build and deploy applications.

Additionally, Tekton also provides support for Windows containers and an ability to run Linux-only, Windows-only as well as hybrid workflows. Installing Tekton on an EKS cluster means EKS automatically manages the availability and scalability of the Kubernetes control plane nodes responsible for scheduling containers, managing application availability, storing cluster data, and other key tasks. In addition, it allowed us to take advantage of all the performance, scale, reliability, and availability of AWS infrastructure, as well as integrations with AWS networking and security services, such as application load balancers (ALBs) for load distribution, AWS Identity and Access Management (IAM) integration with role-based access control (RBAC), and AWS Virtual Private Cloud (VPC) support for pod networking.


In summary, integrating Tekton with Buildpacks allowed us to containerize applications easily and securely and create an end-to-end CI/CD pipeline with reusable components. Using Tekton and buildpacks we were able to containerize more than 20 .NET applications and move them to the cloud in less than six months. This initiative will reduce the technical debt by reducing application maintenance costs by 50% and increasing technical compliance score by 35% in the next two years. 

About the Author

Prerak Patel is DevOps Engineer from the Karsun Solutions DevSecOps Practice. This practice is responsible for driving CI/CD, security engineering, SRE, pipelines and observability excellence at Karsun.