When comparing Yarn vs Gulp, the Slant community recommends Gulp for most people. In the question“What are the best Node.js build systems / task runners?” Gulp is ranked 1st while Yarn is ranked 4th. The most important reason people chose Gulp is:
Currently gulp offers a selection of 1000+ [plugins](http://gulpjs.com/plugins/) and it is growing rapidly.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro The same results will be yielded every time yarn is run in a repository
One of the most important aspects of Yarn is determinism (predictability). The lock file ensures that the same dependencies will always be installed in the same way and order regardless of the machine for a given repository.
Pro Can tell you why a package was installed
yarn why <query>
can tell you why a package was installed and what other packages depend on it.
Pro Good network performance
Yarn efficiently queues up requests and avoids request waterfalls in order to maximize network utilization.
Pro Offline mode
If you've installed a package before, you can install it again without any internet connection.
Pro Flat Mode
Resolve mismatching versions of dependencies to a single version to avoid creating duplicates.
Pro Multiple registries
Install any package from either npm or Bower and keep your package workflow the same.
Pro Network resilience
A single request failing won't cause an install to fail. Requests are retried upon failure.
Pro Good documentation
It looks like it has good documentation.
Pro Security is put at the forefront
Even though it's still in its early stages of development, security is one of the core values on which Yarn is built. It uses checksums to verify the integrity of every package before executing its code. This also helps avoiding errors related to faulty caching or captive portals.
Further steps are also being taken to improve the security of Yarn which will be implemented in the future.
Pro Built by the community for the community
Even though it's backed by Facebook, Yarn is built as a community project first and foremost. It's completely open source and hosted on Github. It's released under a standard open source client and has its own GitHub organization and set up to work under the same governance model that other successful projects have used in the past, such as Rust and Ember.
All of this means that both existing and new contributors will always work together to improve the product and introduce new features while also keeping in mind suggestions coming from the community.
Pro Backed by Facebook and Google
Was created in a collaboration of Facebook with Exponent, Google and Tilde.
Pro Large plugin ecosystem
Currently gulp offers a selection of 1000+ plugins and it is growing rapidly.
Pro Focuses on code instead of configuration
This depends on your style, but gulp is closer to the code, the actual execution isn't hidden by multiple layers and it's much easier to customize the build system without writing bloated modules. This also brings rather small configuration files.
Pro Allows creating task dependencies
Any task can be set to have other tasks as dependencies. The dependencies are specified through piping streams, and tasks run concurrently if they do not block in dependencies.
Pro It is possible to use projects that use streams without plugins
Since Gulp just uses streams at its core, you don't actually need a plugin wrapper to use a project that uses streams. If you use this approach, the you don't even have to worry about plugin maintenance at all, and get the bleeding edge updates as soon as they come out even if the plugin hasn't been updated. It also means if a project happens to not have a plugin, you don't need to write a new one, you can just use it as is.
Pro Streaming build system makes it easier to apply code transformations
In gulp, it's easy to pipe multiple steps together which you commonly need with build systems. For example, you may need to compile the javascript source files, then package them together, and then minify it. The streaming system makes this much easier.
Additionally, it improves performance since all operations are done in memory (compared to I/O operations) and avoids the need of unnecessarily compiling files (compared to Grunt that has to compile all files even if just one has changed).
Pro Chaining API that's simple and elegant
In Gulp, the transforms are performed through chains which makes it easier to understand the order of operations, and easier to modify it.
Pro Concurrency allows for high-speed perfomance
Because streams in Gulp use pipes to establish dependency order, they are parallel by default without having to rely on plugins or hacks.
Pro Minimizes disk operations for improved performance
Because Gulp is built using streams, it can store intermediate transformations in memory and defer writing to disk until the very end. This improves performance by not requiring expensive blocking disk operations for task dependencies.
Pro The configuration file is easily readable
Gulp's configuration file is actually very readable because it's actual JavaScript instead of a large file of JSON objects. The entry barrier is very low for developers who have never used a task runner before and it's API is very simple, with only 4 methods.
Pro Gulp modules are usable without Gulp
Because Gulp is built on top of the streaming API, you don't actually need gulp to use them. This could be helpful if you want to re-use those modules outside of gulp, possibly for testing, and using the same modules would be more consistent.
Pro Gulp tasks run from terminal
Cons
Con Takes up disk space
Yarn adds to your disk space usage since it stores dependencies locally.
Con Dead
Gulp is dead, hasn't been updated in 4 years.
Con Rapidly changing API
While it's good that the gulp maintainers want the api to be as good as possible, it comes at the expense of stability. The upcoming gulp 4.0 release has another update to the way dependency management works which will require everyone to update their build scripts.
It also makes it hard to look up information on best practices as the best practices keep changing, making a lot of the blog posts and questions about gulp out of date.
Con You need to know some limitations that are not very intuitive
There are some features in Gulp which may not be very intuitive, or that otherwise should have been the default features instead of having to implement them through arguments. For example, to keep the correct folder structure when you are copying a file, you have to add {base: "lib/"}
as an argument.
Con No incremental building
Con Not suited for big and complex apps
Writing gulpfile for complex app which consists of many source types is very cumbersome and flawy process. You'll know when you want to move to webpack.