Rust
A language that refuses to compile code with a whole family of memory bugs in it, used where a crash or a breach is unacceptable.
Definition
Most serious security holes in low level software come from the same root cause: memory used after it was released, or written past its end. Rust makes those states impossible to express rather than merely discouraged, and it does so without a garbage collector, so it stays fast enough for operating systems and browser engines.
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