diff --git a/TESTING.md b/TESTING.md
index 5005f7f6..fe83babd 100644
--- a/TESTING.md
+++ b/TESTING.md
@@ -20,10 +20,16 @@ invoke test
 
 This assumes you have installed, on your path:
 
-- python
+- python (with requirements in requirements.txt)
 - invoke
 - docker-compose
 
+Before the first test, run the following:
+
+```
+invoke update-image
+```
+
 The `invoke-test` command performs the following sequence of actions:
 
 - Ensures the test InvenTree server is running (in a docker container)
diff --git a/requirements.txt b/requirements.txt
index 26b588da..fed022f9 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,6 @@
 requests==2.21.0                # Python HTTP for humans
 flake8==3.8.4                   # PEP checking
 wheel>=0.34.2                   # Building package
-invoke>=1.4.0
\ No newline at end of file
+invoke>=1.4.0
+coverage>=6.4.1                 # Run tests, measure coverage
+Pillow>=9.1.1
\ No newline at end of file