The usual suspects for things missing from go are the following: Generics, sum types, match statements, tuple types, compile-time data-race detection, type-safe

The usual suspects for things missing from go are the following: Generics, sum types, match statements, tuple types, compile-time data-race detection, type-safe concurrent-maps, hygienic macros, immutable types/references, functional constructs such as 'map', 'filter', or monads, marker interfaces, better error handling, type-inference for consts that isn't garbage, etc. Less common complaints are that it's missing: object oriented features like inheritance, a configurable gc (as java has), the ability to work with OS threads, c-compatible stacks for fast c-interop, ownership semantics, type-inference for arguments (e.g. as haskell does), operator overloading, dependent types, etc. The list of things in the first set can mostly be summed up as "go has a worse type-system than C++/rust/etc, something much closer to java 1 before generics, or c". Basically, the language is intentionally crippled because it intentionally ignores advances in type-theory that have been shown to allow expressing many things more safely. For example, sum types and match statements make modifying code much safer. People will write switch/if-else-ladder code to do exactly the same sort of thing even without them, the code will just fail at runtime rather than compile-time when a new variant is added or one is not handled by accident.