Systems programming

System programming (or systems programming) is the activity of programming computer system software. The primary distinguishing characteristic of systems programming when compared to application programming is that application programming aims to produce software which provides services to the user directly (e.g. word processor), whereas systems programming aims to produce software and software platforms which provide services to other software, are performance constrained, or both (e.g. operating systems, computational science applications, game engines and AAA video games, industrial automation, and software as a service applications).

System programming requires a great degree of hardware awareness. Its goal is to achieve efficient use of available resources, either because the software itself is performance critical (AAA video games) or because even small efficiency improvements directly transform into significant monetary savings for the service provider (cloud based word processors).

The following attributes characterize systems programming:

Systems programming is sufficiently different from application programming that programmers tend to specialize in one or the other.

In system programming, often limited programming facilities are available. The use of automatic garbage collection is not common and debugging is sometimes hard to do. The runtime library, if available at all, is usually far less powerful, and does less error checking. Because of those limitations, monitoring and logging are often used; operating systems may have extremely elaborate logging subsystems.

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