diff --git a/VERSION b/VERSION
new file mode 100644
index 0000000..8acdd82
--- /dev/null
+++ b/VERSION
@@ -0,0 +1 @@
+0.0.1
diff --git a/docs/build.md b/docs/build.md
index 1ba59c3..03c21a7 100644
--- a/docs/build.md
+++ b/docs/build.md
@@ -1,6 +1,7 @@
 Building and releasing the GDPR API Tester
 ==========================================
 
+Update version number in `VERSION` file.
 
 # GitHub package
 
diff --git a/pyproject.toml b/pyproject.toml
index 9b89e42..880d1ee 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,5 @@
 [project]
 name = "gdpr-api-tester"
-version = "0.0.1"
 authors = [
   { name="Mikko Keskinen", email="mikko.keskinen@hel.fi" },
 ]
@@ -16,7 +15,7 @@ classifiers = [
     "Programming Language :: Python :: 3",
     "Topic :: Software Development :: Quality Assurance",
 ]
-dynamic = ["dependencies"]
+dynamic = ["dependencies", "version"]
 
 [project.urls]
 "Homepage" = "https://github.com/City-of-Helsinki/profile-gdpr-api-tester"
@@ -31,6 +30,7 @@ build-backend = "setuptools.build_meta"
 
 [tool.setuptools.dynamic]
 dependencies = {file = ["requirements.txt"]}
+version = {file = "VERSION"}
 
 [tool.setuptools.packages]
 find = {}