I find the Process API with Process.new and Process.run confusing, often mixing both forgetting which one is blocking or non-blocking. Another pain point compared to said, Python, is to easily create Strings from the STDOUT and STDERR from a subprocess. I created https://github.com/j8r/exec.cr to …

I would say that process management in Crystal is not very usable in general at the moment. The most common use-case would probably be this: block the current fiber until the child exits, then give me its exit status, stdout and stderr. A slight tweak would be to additionally feed its stdin. The ot…

I also have trouble with the Process syntax because the defaults require a lot of arguments and it is not always clear whether is is blocking or not. In all my projects I write some kind of helper method that wraps Process because of that. Clarify blocking v. non-blocking I’m not sure why Process …

shell: true invokes a /bin/sh -c 'mycommand' subprocesss that executes the command (so it may also create a sub-subprocess). shell: false directly execute the command, you need to have the arguments “pre-parsed” as an Enumerable.

And unless you use exec in the shell command you will get neither the pid, nor the exit status of your command run by shell.

At least I am not alone to find room for improvement in Process :slightly_smiling_face:. I’ll open an RFC.

Didn’t realise this thread existed because it was one of my points in Stdlib - A mixed discussion about some modules . If you have an RFC, I’d be interested in seeing it!

Improve Process API

Crystal Contrib

straight-shoota March 10, 2026, 5:21pm 8

There is some movement on the Process API: RFC 0025: Modern Process Spawn API proposes changes that cover most of the suggestions by @paulcsmith here.

2 Likes

Topic		Replies	Views
RFC 0025: Modern Process Spawn API Crystal Contrib rfc	0	74	March 10, 2026
Stdlib - A mixed discussion about some modules Crystal Contrib	3	639	July 26, 2019
Process::ORIGINAL_STDOUT and ORIGINAL_STDERR change Help & Support	4	695	May 9, 2023
How to run a command but not wait for it to return? Help & Support	1	230	May 9, 2024
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Improve Process API

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