[rustc.git] / src / doc / edition-guide / src / rust-2018 / cargo-and-crates-io / cargo-new-defaults-to-a-binary-project.md

# `cargo new` defaults to a binary project

![Minimum Rust version: 1.25](https://img.shields.io/badge/Minimum%20Rust%20Version-1.25-brightgreen.svg)

`cargo new` will now default to generating a binary, rather than a library.
We try to keep Cargo’s CLI quite stable, but this change is important, and is
unlikely to cause breakage.

For some background, `cargo new` accepts two flags: `--lib`, for creating
libraries, and `--bin`, for creating binaries, or executables. If you don’t
pass one of these flags, it used to default to `--lib`. At the time, we made
this decision because each binary (often) depends on many libraries, and so
we thought the library case would be more common. However, this is incorrect;
each library is depended upon by many binaries. Furthermore, when getting
started, what you often want is a program you can run and play around with.
It’s not just new Rustaceans though; even very long-time community members
have said that they find this default surprising. As such, we’ve changed it,
and it now defaults to `--bin`.
Commit	Line	Data
450edc1f XL	1	# `cargo new` defaults to a binary project
	2
	3	![Minimum Rust version: 1.25](https://img.shields.io/badge/Minimum%20Rust%20Version-1.25-brightgreen.svg)
	4
	5	`cargo new` will now default to generating a binary, rather than a library.
	6	We try to keep Cargo’s CLI quite stable, but this change is important, and is
	7	unlikely to cause breakage.
	8
dc9dc135	9	For some background, `cargo new` accepts two flags: `--lib`, for creating
450edc1f XL	10	libraries, and `--bin`, for creating binaries, or executables. If you don’t
	11	pass one of these flags, it used to default to `--lib`. At the time, we made
	12	this decision because each binary (often) depends on many libraries, and so
	13	we thought the library case would be more common. However, this is incorrect;
	14	each library is depended upon by many binaries. Furthermore, when getting
	15	started, what you often want is a program you can run and play around with.
	16	It’s not just new Rustaceans though; even very long-time community members
	17	have said that they find this default surprising. As such, we’ve changed it,
	18	and it now defaults to `--bin`.