Hi Bryce,

Sorry: I wasn't clear about how to reproduce!

I've been doing it exactly the way you've tried: "touch sitecustomize.py".

Using "snap run --strace":

  % rm -rf strace.log* __pycache__
  % snap run --strace='-tt -f -o strace.log -s 128' ppa-dev-tools.ppa &>/dev/null
  % grep sitecustomize strace.log.*

Do you get anything from grep?

I tried with 0.5.0 too and I experience the same thing.

For reference, an excerpt of strace's output here:

09:46:50.267472 newfstatat(AT_FDCWD, "/snap/ppa-dev-tools/74/local/lib/python3.10/dist-packages", 0x7ffe08010150, 0) = -1 ENOENT (No such file or directory)
09:46:50.267497 newfstatat(AT_FDCWD, "/snap/ppa-dev-tools/74/lib/python3/dist-packages", 0x7ffe08010150, 0) = -1 ENOENT (No such file or directory)
09:46:50.267519 newfstatat(AT_FDCWD, "/snap/ppa-dev-tools/74/lib/python3.10/dist-packages", 0x7ffe08010150, 0) = -1 ENOENT (No such file or directory)
09:46:50.267566 newfstatat(AT_FDCWD, "/snap/ppa-dev-tools/74/lib/python3.10/site-packages", {st_mode=S_IFDIR|0755, st_size=308, ...}, 0) = 0
09:46:50.267599 openat(AT_FDCWD, "/snap/ppa-dev-tools/74/lib/python3.10/site-packages", O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_DIRECTORY) = 3
09:46:50.267620 newfstatat(3, "", {st_mode=S_IFDIR|0755, st_size=308, ...}, AT_EMPTY_PATH) = 0
09:46:50.267643 getdents64(3, 0x64f361297d60 /* 13 entries */, 32768) = 480
09:46:50.267665 getdents64(3, 0x64f361297d60 /* 0 entries */, 32768) = 0
09:46:50.267683 close(3)                = 0
09:46:50.267711 openat(AT_FDCWD, "/snap/ppa-dev-tools/74/lib/python3.10/site-packages/distutils-precedence.pth", O_RDONLY|O_CLOEXEC) = 3
09:46:50.267733 newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=151, ...}, AT_EMPTY_PATH) = 0
09:46:50.267753 ioctl(3, TCGETS, 0x7ffe0800fde0) = -1 ENOTTY (Inappropriate ioctl for device)
09:46:50.267776 lseek(3, 0, SEEK_CUR)   = 0
09:46:50.267795 ioctl(3, TCGETS, 0x7ffe080100b0) = -1 ENOTTY (Inappropriate ioctl for device)
09:46:50.267821 read(3, "import os; var = 'SETUPTOOLS_USE_DISTUTILS'; enabled = os.environ.get(var, 'local') == 'local'; enabled and __import__('_distuti"..., 8192) = 151
09:46:50.267894 read(3, "", 8192)       = 0
09:46:50.267917 close(3)                = 0
09:46:50.267937 newfstatat(AT_FDCWD, "/snap/ppa-dev-tools/74/local/lib/python3.10/dist-packages", 0x7ffe08010330, 0) = -1 ENOENT (No such file or directory)
09:46:50.267960 newfstatat(AT_FDCWD, "/snap/ppa-dev-tools/74/lib/python3/dist-packages", 0x7ffe08010330, 0) = -1 ENOENT (No such file or directory)
09:46:50.267980 newfstatat(AT_FDCWD, "/snap/ppa-dev-tools/74/lib/python3.10/dist-packages", 0x7ffe08010330, 0) = -1 ENOENT (No such file or directory)
09:46:50.268041 newfstatat(AT_FDCWD, "/snap/ppa-dev-tools/74/lib/python3.10/site-packages", {st_mode=S_IFDIR|0755, st_size=308, ...}, 0) = 0
09:46:50.268073 newfstatat(AT_FDCWD, "/snap/ppa-dev-tools/74/usr/lib/python3/dist-packages", {st_mode=S_IFDIR|0755, st_size=1686, ...}, 0) = 0
09:46:50.268100 newfstatat(AT_FDCWD, "/home/adrien/public/ubuntu/t/t", {st_mode=S_IFDIR|0775, st_size=4096, ...}, 0) = 0
09:46:50.268126 newfstatat(AT_FDCWD, "/home/adrien/public/ubuntu/t/t/sitecustomize.py", {st_mode=S_IFREG|0664, st_size=0, ...}, 0) = 0
09:46:50.268171 newfstatat(AT_FDCWD, "/home/adrien/public/ubuntu/t/t/sitecustomize.py", {st_mode=S_IFREG|0664, st_size=0, ...}, 0) = 0
09:46:50.268197 openat(AT_FDCWD, "/home/adrien/public/ubuntu/t/t/__pycache__/sitecustomize.cpython-310.pyc", O_RDONLY|O_CLOEXEC) = 3