Different languages will probably replace different parts of C usage. I suspect Go will replace C/C++ for high performance server side stuff like databases and

Different languages will probably replace different parts of C usage. I suspect Go will replace C/C++ for high performance server side stuff like databases and various server software. E.g. I've seen a bitcoin server being written in Go. That is the sort of stuff that makes sense for Go I think. However C is often used for writing libraries that can be used for many languages. Think about OpenSSL e.g. I doubt C was chosen due to its credentials as a secure language. Rather this is a liability for C/C++ in many areas. I think Rust will replace this. Actually I think Swift will be fighting with Rust over some of the the same territory. They both got the same advantage of not requiring a garbage collector and thus can be used to write libraries to be used by any language through a C-API. While Rust might have an edge language wise, Swift might be just good enough. That matters because we are using C/C++ not so much due to the quality of those languages but due to a combination of their feature set and existing momentum. Swift is more or less guaranteed to get big as it is replacing Objective-C for iOS development rapidly. That will create a large user base for it quickly. This will only accelerate when Swift goes open source and can be used on more platforms. Both D and Rust have a bit of a chicken and egg problem. People aren't going to use those languages if people don't believe they have a future. They wont have a future if people don't believe they have a future. Rust is novel and cool enough in a geek perspective that I think it will gain enough momentum to get some presence. D has been around for a long time without that happening so there is no reason to believe it will happen now. Swift has the chicken and egg problem solved. For writing something like OpenSSL it would take away many potential problems. No accidentally not executed code due to not using curly braces for if statements. No exploitable buffer or integer overflows. No accidentally uninitialized variables. No accidental switch-case fall through. No unintentional type conversions. A whole host of memory bugs gone.