Nix shell is spawned on every command

[igor-sirotin]

Description

foo:
	echo 1
	echo 2

And when I run this from usual terminal:

> make foo
echo 1
Configuring Nix shell for target 'default'...
1
echo 2
Configuring Nix shell for target 'default'...
2

Obviously, it's not like that when I run it from make shell:

> make shell
[nix] > make foo
echo 1
1
echo 2
2

Because it was fixed here:

• fix(nix)_: allow re-useing of existing Nix shell #6459

What's the issue?

1. Since we automatically spawn nix-shell on every Makefile target, as a developer I would assume that it should work, and make shell is not a required prerequisite.
   But this doesn't happen. And spawning a nix-shell on each has 2 drawbacks:

   • Time consuming (4 second on each command)
   • The target command continues to execute even after an error:

   foo:
       echo 1; \
       go foo; \
       echo 3

   > make foo
   Configuring Nix shell for target 'default'...
   1
   go foo: unknown command
   Run 'go help' for usage.
   3

2. CI doesn't do make shell ☝
   Looking at any last successful CI build, we can see that Nix shell is started a few times. And we can see that gomobile init fails, but gomobile bind is still executed

[2025-05-14T13:45:16.816Z] �[0;32mConfiguring Nix shell for target 'default'...�[0m
[2025-05-14T13:45:19.009Z] Building status-go for iOS...
[2025-05-14T13:45:19.009Z] export GO111MODULE=off; \
[2025-05-14T13:45:19.009Z] gomobile init; \
[2025-05-14T13:45:19.009Z] gomobile bind -v \
[2025-05-14T13:45:19.009Z] 	-target=ios -ldflags="-s -w" \
[2025-05-14T13:45:19.009Z] 	-tags 'nowatchdog gowaku_no_rln disable_torrent' \
[2025-05-14T13:45:19.009Z] 	 \
[2025-05-14T13:45:19.009Z] 	-o build/bin/Statusgo.xcframework \
[2025-05-14T13:45:19.009Z] 	github.com/status-im/status-go/mobile
[2025-05-14T13:45:19.009Z] �[0;32mConfiguring Nix shell for target 'default'...�[0m
[2025-05-14T13:45:22.763Z] /nix/store/i6wd00maj94ah6bsyasdd21dxircxsjs-gomobile-0-unstable-2024-12-13/bin/gomobile: go install golang.org/x/mobile/cmd/gobind failed: exit status 1
[2025-05-14T13:45:22.763Z] /nix/store/i6wd00maj94ah6bsyasdd21dxircxsjs-gomobile-0-unstable-2024-12-13/src/golang.org/x/mobile/internal/importers/ast.go:39:2: cannot find package "golang.org/x/tools/go/packages" in any of:
[2025-05-14T13:45:22.763Z] 	/nix/store/i04a1a6qgxhjw6c0ld2b3x1v815sbxjc-go-1.22.3/share/go/src/golang.org/x/tools/go/packages (from $GOROOT)
[2025-05-14T13:45:22.763Z] 	/Users/jenkins/workspace/status-go_prs_ios_PR-6519@tmp/go/src/golang.org/x/tools/go/packages (from $GOPATH)
[2025-05-14T13:45:22.763Z] 	/nix/store/i6wd00maj94ah6bsyasdd21dxircxsjs-gomobile-0-unstable-2024-12-13/src/golang.org/x/tools/go/packages
[2025-05-14T13:45:22.763Z] 
[2025-05-14T13:45:58.533Z] internal/godebugs
[2025-05-14T13:45:58.533Z] internal/goexperiment
[2025-05-14T13:45:58.533Z] internal/goarch
[2025-05-14T13:45:58.533Z] internal/itoa
[2025-05-14T13:45:58.533Z] internal/goos
[2025-05-14T13:45:58.533Z] internal/unsafeheader
[2025-05-14T13:45:58.533Z] internal/godebugs
[2025-05-14T13:45:58.533Z] internal/goexperiment
[2025-05-14T13:45:58.533Z] internal/goos
[2025-05-14T13:45:58.533Z] internal/cpu
[2025-05-14T13:45:58.533Z] internal/itoa
[2025-05-14T13:45:58.533Z] math/bits
... `gomobile bind` continues

[igor-sirotin]

I suppose this fixes this issue though 🤔

• feat(development)_: add nix flake and expose devshells and packages through it #6529

But then we need to make sure that gomobile init works with no errors

cc @siddarthkay @markoburcul

[markoburcul]

I suppose this fixes this issue though 🤔

This is not directly aimed to solve the issue you're presenting, but sure, I can take a look at it and try to resolve it within that PR :D

[markoburcul]

Hi @igor-sirotin , I've played a bit with your example and we can solve this in few ways. Let's get back to the example:

foo:
   echo 1; \
   go foo; \
   echo 3

The issue is that you're using shell command continuation with backslashes, which combines all commands into a single shell command. When you do this, the shell continues executing subsequent commands even if one fails.
Now we could either do this:

foo:
   echo 1
   go foo
   echo 2

or this:

foo:
   echo 1 && \
   go foo && \
   echo 2

or even this:

foo:
   set -e; \
   echo 1; \
   go foo; \
   echo 2

to stop execution when error occurs. I see only for statusgo-android and statusgo-ios targets we have this kind of issue with gomobile init.

Regarding the comment about nix shell, I'm not sure if I understood it well. Do you want nix shell to be executed always before any of the target or do you want to have the choice of executing it yourself beforehand and then execute whatever target you want?

[jakubgs]

Obviously, it's not like that when I run it from make shell:

That's actually not true. This is how make works and always worked, each separate command in a target spawns a new shell.

This is why people use these && tricks to make it one command.

I think the simplest way to avoid the Nix shell confusion is to disentangle Nix shell from the Makefile and simply educate engineers (maybe through a warning in make) that they can start a Nix shell with make shell or nix develop and everything should work, or not do that and suffer the consequences of using non-standard tooling.

[igor-sirotin]

disentangle Nix shell from the Makefile

@jakubgs yes, this is the our best choice I believe.
This would also allow developers to use whatever tools they want, if they don't want to use Nix (for whatever reason). And we can then separate any Makefile issues from Nix issues.

--

@markoburcul Thanks for your explanation. Indeed maybe I'm confusing different issues here.

[jakubgs]

Cool, then as part of introduction of Nix flakes we should aim to remove Nix from Makefile and make it clear to devs through docs, messaging, and possibly a Makefile warning that Nix shell is them for them to use, and if they don't want to then HERE BE DRAGONS.

[igor-sirotin]

Closing as done