What this snippet does
Grouping ENV assignments into one instruction keeps the layer count down.
Expected output
Successfully built 8b2d5f1a4c37
Why practise typing this
Typing env & arg code builds muscle memory for the symbols and indentation Docker uses most, which prose-based typing tests never cover. DevType measures your words per minute and accuracy on this snippet and tracks the individual characters you mistype, so later lessons can target them.
More Docker practice
- Setting an environment variableENV & ARG · beginner
- Build-time argumentENV & ARG · intermediate
- ARG is gone at runtimeENV & ARG · intermediate
- ARG before FROM has limited scopeENV & ARG · advanced
- Parameterised base imageENV & ARG · advanced
- Secrets leak through build argsENV & ARG · advanced