Getting an import error while building a conda recipe

Question

I have a Python package named httomolib, https://github.com/DiamondLightSource/httomolib/ and I am trying to make it available on anaconda cloud. I wrote a conda recipe for it; the meta.yml file contains:

{% set name = "httomolib" %}
{% set version = "0.0.1" %}

package:
  name: {{ name|lower }}
  version: {{ version }}

source:
  path: ..

build:
  preserve_egg_dir: False
  script: {{ PYTHON }} -m pip install -e .
  number: 0

requirements:
  host:
    - python
    - pip
    - setuptools
  run:
    - python
    - cupy
    - numpy
    - scipy
    - pillow
    - scikit-image
    - pytest

test:
  requires:
    - pip
    - pytest
  imports:
    - httomolib
    - httomolib.misc
    - httomolib.prep
    - httomolib.recon
  source_files:
    - tests/*
  commands:
    - pip check
    - pytest

about:
  home: https://github.com/DiamondLightSource/httomolib
  summary: 'A library of data processing and reconstruction methods for tomography'
  description: |
    A library of data processing and reconstruction methods for tomography

While building and testing the recipe for a specific python and numpy version (conda build recipe --numpy 1.21 --python 3.9 ), I get an import error

ModuleNotFoundError: No module named 'httomolib'

Any ideas what is missing in the recipe here, python or setuptools specific? (Note that recipe is the folder containing meta.yml)

Thanks in advance.