CUE distinguishes the bytes type from the string type. Byte literals are defined with single quotes.

In addition to the escape sequences permitted in string literals, byte literals also allow these escape sequences:

\xnnArbitrary byte value defined as the 2-digit hexadecimal number “nn
\nnnArbitrary byte value defined as the 3-digit octal number “nnn

Bytes are represented as Base64 when exporting concrete data to a format such as JSON or YAML.
To avoid this, interpolate bytes inside a string value.

aString: "A string"

// Multiple representations of the same underlying
// bytes, which therefore unify succesfully.
Bytes: 'A string'
Bytes: '\(aString)'
Bytes: '\x41\x20\x73\x74\x72\x69\x6e\x67'
Bytes: '\101\040\163\164\162\151\156\147'

stringBytes: "\(Bytes)"
$ cue export file.cue
    "aString": "A string",
    "Bytes": "QSBzdHJpbmc=",
    "stringBytes": "A string"