What this snippet does
Copying the whole tree before installing busts the install cache on every single source edit.
Expected output
=> [4/4] RUN npm ci 38.2s
Why practise typing this
Typing layers & caching 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
- Dependencies before sourceLayers & Caching · intermediate
- Chaining to one layerLayers & Caching · intermediate
- Deleting in a later layerLayers & Caching · intermediate
- BuildKit cache mountLayers & Caching · advanced
- Go module cacheLayers & Caching · advanced
- Inspecting layer sizesLayers & Caching · intermediate