As well as let assignments Gleam also has constants, which are defined at the top level of a module.

Constants must be literal values, functions cannot be used in their definitions.

Constants may be useful for values that are used throughout your program, permitting them to be named and to ensure there are no differences in the definition between each use.

Using a constant may be more efficient than creating the same value in multiple functions, though the exact performance characteristics will depend on the runtime and whether compiling to Erlang or JavaScript.