diff --git a/README.md b/README.md
index 7239b24d..02638474 100644
--- a/README.md
+++ b/README.md
@@ -381,6 +381,8 @@ Please follow the steps below to run the tests locally:
 
     - See [docs on running pytest-workflow](https://pytest-workflow.readthedocs.io/en/stable/#running-pytest-workflow) for more info.
 
+> :warning: if you have a module named `build` this can conflict with some pytest internal behaviour. This results in no tests being run (i.e. recieving a message of `collected 0 items`). In this case rename the `tests/<module>/build` directry to `tests/<module>/build_test`, and update the corresponding `test.yml` accordingly. An example can be seen with the [`bowtie2/build` module tests](https://github.com/nf-core/modules/tree/master/tests/modules/bowtie2/build_test).
+
 ### Uploading to `nf-core/modules`
 
 [Fork](https://help.github.com/articles/fork-a-repo/) the `nf-core/modules` repository to your own GitHub account. Within the local clone of your fork add the module file to the [`modules/`](modules) directory. Please try and keep PRs as atomic as possible to aid the reviewing process - ideally, one module addition/update per PR.