diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index b147994..5de9119 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -1,6 +1,6 @@
 name: CI
 
-on: [push, pull_request]
+on: [pull_request]
 
 jobs:
   tests:
diff --git a/gnlse/common.py b/gnlse/common.py
index e3051b7..a0e5003 100644
--- a/gnlse/common.py
+++ b/gnlse/common.py
@@ -1 +1,5 @@
+pi = 3.1415926535897932384626433
+
 c = 299792.458  # Speed of light in vacuum [nm/ps]
+hplanck = 6.62607015e-34  # Planck constant [J.s]
+hbar = hplanck / 2 / pi  # Reduced Planck constant [J.s]