ko vs Tilt

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.

Tilt is a free, open-source development environment for teams building microservice applications that deploy to Kubernetes. It watches files, builds container images and updates the development environment when code changes. Its live_update feature deploys changes to running containers in seconds, including compiled-language code or dependency changes. Tilt can start the application and automate rebuilds, with logs, broken builds and runtime errors in its feedback loop. Its UI collects service logs and shows the development environment's state.

Teams configure services and workflows with Tiltfiles using Kubernetes YAML and Docker images; documentation also describes integrating Bazel builds. Tilt has an extension system for sharing Tiltfile functionality, such as team scripts and custom buttons, and provides editor support for VS Code, selected JetBrains IDEs and other editors through an embedded language server. It runs on macOS, Linux and Windows. The standard setup requires Docker, kubectl and a local Kubernetes cluster, though workflows can also use options such as Helm, Podman or local processes. Tilt is maintained as open source by Docker, Inc. under the Apache-2.0 license and costs nothing.