While is a goldmine for MQL4 libraries and indicators, a functional EX4 decompiler is a "white whale." Most repositories you find will either be outdated or highly technical tools for reverse engineers. If you’ve lost your source code, your best bet is often a manual rewrite rather than relying on automated decompilation.
Most "decompilers" you will find on GitHub today fall into two categories: Wrappers (Not Decompilers): Projects like FX31337/ex4_to_mq4_cli ex4 decompiler github
Before MetaQuotes updated the MT4 platform (specifically after Build 600), decompilers were common. The old EX4 files were essentially obfuscated scripts that could be easily reverted to readable MQ4 code. While is a goldmine for MQL4 libraries and