diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 939e704..844de13 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -144,25 +144,48 @@ jobs:
     if: github.event_name == 'push'
     runs-on: ubuntu-latest
     steps:
+      - name: Checkout
+        uses: actions/checkout@v7
+
+      - name: Get version
+        id: version
+        env:
+          PYTHONPATH: src
+        run: python -c "from version import VERSION; print(f'version={VERSION}')" >> "$GITHUB_OUTPUT"
+
+      - name: Check tag
+        id: tag
+        env:
+          VERSION: ${{ steps.version.outputs.version }}
+        run: |
+          if git ls-remote --exit-code --tags origin "refs/tags/${VERSION}" > /dev/null; then
+            echo "exists=true" >> "$GITHUB_OUTPUT"
+          else
+            status=$?
+            if [ "$status" -ne 2 ]; then
+              exit "$status"
+            fi
+            echo "exists=false" >> "$GITHUB_OUTPUT"
+          fi
+
       - name: Download artifacts
+        if: steps.tag.outputs.exists == 'false'
         uses: actions/download-artifact@v8
 
-      - name: Get date
-        id: date
-        run: echo "date=$(date +%Y.%m.%d)" >> "$GITHUB_OUTPUT"
-
       - name: Rename artifacts
+        if: steps.tag.outputs.exists == 'false'
         env:
-          VERSION: ${{ steps.date.outputs.date }}.${{ github.run_number }}
+          VERSION: ${{ steps.version.outputs.version }}
         run: |
           mv snapjaw-windows-x86_64/snapjaw-windows-x86_64.zip snapjaw-${VERSION}-windows-x86_64.zip
           mv snapjaw-linux-x86_64/snapjaw-linux-x86_64.tar.gz snapjaw-${VERSION}-linux-x86_64.tar.gz
 
       - name: Release
+        if: steps.tag.outputs.exists == 'false'
         uses: softprops/action-gh-release@v3
         with:
-          tag_name: ${{ steps.date.outputs.date }}.${{ github.run_number }}
-          name: ${{ steps.date.outputs.date }}.${{ github.run_number }}
+          tag_name: ${{ steps.version.outputs.version }}
+          name: ${{ steps.version.outputs.version }}
           files: |
-            snapjaw-${{ steps.date.outputs.date }}.${{ github.run_number }}-windows-x86_64.zip
-            snapjaw-${{ steps.date.outputs.date }}.${{ github.run_number }}-linux-x86_64.tar.gz
+            snapjaw-${{ steps.version.outputs.version }}-windows-x86_64.zip
+            snapjaw-${{ steps.version.outputs.version }}-linux-x86_64.tar.gz
diff --git a/pyproject.toml b/pyproject.toml
index 30bd7d3..f907a76 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -13,7 +13,7 @@ dependencies = [
     "tabulate>=0.9.0",
 ]
 name = "snapjaw"
-version = "1.0"
+dynamic = ["version"]
 description = "Vanilla WoW AddOn Manager"
 
 [tool.ruff]
diff --git a/src/snapjaw.py b/src/snapjaw.py
index c430643..86c514d 100644
--- a/src/snapjaw.py
+++ b/src/snapjaw.py
@@ -24,6 +24,7 @@
 import mygit
 import signature
 import toc
+import version
 
 
 class CliError(RuntimeError):
@@ -79,6 +80,7 @@ def main():
 
 def parse_args():
     parser = argparse.ArgumentParser()
+    parser.add_argument("--version", action="version", version=f"snapjaw {version.VERSION}")
 
     parser.add_argument(
         "--addons-dir",
diff --git a/src/version.py b/src/version.py
new file mode 100644
index 0000000..af63e4a
--- /dev/null
+++ b/src/version.py
@@ -0,0 +1 @@
+VERSION = "1.4.0"
diff --git a/tests/test_version.py b/tests/test_version.py
new file mode 100644
index 0000000..014f605
--- /dev/null
+++ b/tests/test_version.py
@@ -0,0 +1,60 @@
+"""Tests for the application version and CLI version flag."""
+
+import re
+
+import pytest
+
+import version
+from snapjaw import parse_args
+
+
+class TestVersion:
+    """Tests for the single source of truth version constant."""
+
+    def test_has_three_numeric_components(self):
+        """VERSION uses semantic versioning's three-component numeric form."""
+        assert re.fullmatch(r"\d+\.\d+\.\d+", version.VERSION)
+
+
+class TestVersionFlag:
+    """Tests for the top-level --version flag."""
+
+    @staticmethod
+    def assert_version_output(monkeypatch, capsys, argv):
+        monkeypatch.setattr("sys.argv", argv)
+
+        with pytest.raises(SystemExit) as error:
+            parse_args()
+
+        assert error.value.code == 0
+        captured = capsys.readouterr()
+        assert captured.out == f"snapjaw {version.VERSION}\n"
+        assert captured.err == ""
+
+    def test_prints_exact_version(self, monkeypatch, capsys, tmp_path):
+        """--version prints the application name and VERSION exactly."""
+        self.assert_version_output(
+            monkeypatch,
+            capsys,
+            [
+                "snapjaw",
+                "--addons-dir",
+                str(tmp_path),
+                "--game-version",
+                "vanilla",
+                "--version",
+                "status",
+            ],
+        )
+
+    def test_works_without_subcommand(self, monkeypatch, capsys):
+        """--version exits before required subcommand validation."""
+        self.assert_version_output(monkeypatch, capsys, ["snapjaw", "--version"])
+
+    def test_works_outside_game_directory(self, monkeypatch, capsys, tmp_path):
+        """--version exits before attempting to resolve an addons directory."""
+        isolated_directory = tmp_path / "isolated"
+        isolated_directory.mkdir()
+        monkeypatch.chdir(isolated_directory)
+
+        self.assert_version_output(monkeypatch, capsys, ["snapjaw", "--version"])
diff --git a/uv.lock b/uv.lock
index 90e45d8..cfee933 100644
--- a/uv.lock
+++ b/uv.lock
@@ -309,7 +309,6 @@ wheels = [
 
 [[package]]
 name = "snapjaw"
-version = "1.0"
 source = { virtual = "." }
 dependencies = [
     { name = "colorama" },