diff --git a/Project.toml b/Project.toml
index 0152f1a7..b1ba0faf 100644
--- a/Project.toml
+++ b/Project.toml
@@ -16,7 +16,7 @@ SpecialMatrices = "928aab9d-ef52-54ac-8ca1-acd7ca42c160"
 UnPack = "3a884ed6-31ef-47d7-9d2a-63182c4928ed"
 
 [compat]
-ApproxFun = "0.12"
+ApproxFun = "0.12, 0.13"
 FFTW = "1.0.0"
 InvertedIndices = "1.1"
 Polynomials = "2.0.24, 3"