AWS CodeBuild vs ko

AWS CodeBuild is a paid, cloud-hosted continuous integration service for compiling, testing, and packaging code from build scripts. It provisions and scales build capacity automatically, so projects do not require users to manage build servers. Preconfigured environments cover Java, Python, Node.js, Ruby, Go, Android, .NET Core for Linux, and Docker; teams can also supply Docker-based environments. A YAML build specification defines commands for each build phase and other settings. Builds can start from CodeCommit, GitHub, GitHub Enterprise, Bitbucket, Amazon S3, or CodePipeline, and can work with Jenkins. Artifacts can be stored in S3 or sent to an artifact repository. IAM provides access controls, while KMS keys encrypt artifacts. Build timing, status, commit ID, metrics, and logs are available through the service and CloudWatch, with SNS event notifications. A free plan provides stated monthly allowances; paid usage starts at 0.01 USD and can add charges for data transfer and related AWS services.

ko is an open-source builder for container images of Go applications. It runs `go build` locally, so Docker does not need to be installed. The project positions it for a single Go application with few operating-system base-image dependencies, such as one without cgo or OS package requirements. Builds can target all platforms supported by the configured base image or selected platforms such as linux/amd64 and linux/arm64. For Kubernetes, `ko resolve` builds images for `ko://` references in YAML and replaces those references with image references; `ko apply` can apply the resolved configuration. ko reuses the normal Go build cache and avoids pushing image blobs already present in the remote registry. It generates and uploads SPDX-format SBOMs by default, with an option to disable this. Registry credentials can come from Docker configuration, with built-in environment credential support for Google, Amazon, Azure, and GitHub container registries. A Terraform provider supports Infrastructure-as-Code workflows. ko supports Go applications only and defaults to CGO_ENABLED=0. Windows container image support is experimental and requires a Windows base image.