1 files changed, 5 insertions, 2 deletions
diff --git a/tox.ini b/tox.ini
index 1b9f056c..ab66ca2f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -13,7 +13,6 @@ usedevelop = True
 download = True
 extras =
     toml
-package = editable
 
 # PYVERSIONS
 deps =
@@ -32,11 +31,15 @@ setenv =
     # so override any local setting.
     PYTHONPYCACHEPREFIX=
 
+# $set_env.py: COVERAGE_PIP_ARGS - Extra arguments for `pip install`
+# `--no-build-isolation` will let tox work with no network.
 commands =
     # Create tests/zipmods.zip
     python igor.py zip_mods
 
-    # Test with the CTracer that normal installation gives us.
+    # Build the C extension and test with the CTracer
+    python setup.py --quiet build_ext --inplace
+    python -m pip install {env:COVERAGE_PIP_ARGS} -q -e .
     python igor.py test_with_tracer c {posargs}
 
     # Remove the C extension so that we can test the PyTracer