diff --git a/Cargo.toml b/Cargo.toml
index c9a0df077b..9441679a95 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -14,6 +14,7 @@ readme = "README.md"
 [dependencies]
 ads1x1x = "0.2.2"
 ak09915_rs= "0.2.0"
+approx = "0.5.1"
 bmp280 = "0.4.0"
 embedded-hal = "0.2.7"
 icm20689 = "0.1.1"