Similar to 'url-fetch' but unpack the file from URL in a directory of its own. This helper makes it easier to deal with "tar bombs".

Like 'url-fetch', but make the downloaded file executable.

Download from URL to STORE, either under NAME or URL's basename if omitted. Write progress reports to LOG. RECURSIVE? has the same effect as the same-named parameter of 'add-to-store'. VERIFY-CERTIFICATE? determines whether or not to validate HTTPS server certificates.

Return a fixed-output derivation that fetches data from URL (a string, or a list of strings denoting alternate URLs), which is expected to have hash HASH of type HASH-ALGO (a symbol). By default, the file name is the base name of URL; optionally, NAME can specify a different file name. When EXECUTABLE? is true, make the downloaded file executable.

When one of the URL starts with mirror://, then its host part is interpreted as the name of a mirror scheme, taken from %MIRROR-FILE.

Alternatively, when URL starts with file://, return the corresponding file name in the store.