Docker image selection for Vela steps; alpine variants, version pinning, pull policies, and recommended images for Go, Node, Python, Java, Rust, Ruby, and .NET.
Choose the right Docker images for your Vela pipeline steps. Prefer alpine variants, pin to major or major.minor versions, and use pull: always for mutable tags. Every step runs inside a Docker container, and image choice directly affects build speed, reliability, and security.
Alpine-based images are significantly smaller and faster to pull. Most official Docker images offer -alpine variants:
# Prefer this