Thank u every one ;) Use botan so easy: ```D import std.stdio; import botan;
void main() {string appKey = "11111111111111111111111111111111111111111111111111111";
auto sha256 = retrieveHash("SHA-256").clone(); sha256.update(appKey);string sign = sha256.finished()[].toHexString!(LetterCase.lower);
writeln("sign: %s", sign); } ```