diff --git a/Project.toml b/Project.toml
index 89dca35e..0ad10ab1 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,6 +1,6 @@
 name = "DiffOpt"
 uuid = "930fe3bc-9c6b-11ea-2d94-6184641e85e7"
-version = "0.5.5"
+version = "0.5.6"
 authors = ["Akshay Sharma", "Mathieu Besançon", "Joaquim Dias Garcia", "Benoît Legat", "Oscar Dowson", "Andrew Rosemberg"]
 
 [deps]
@@ -23,5 +23,5 @@ JuMP = "1"
 LazyArrays = "1, 2"
 MathOptInterface = "1.18"
 MathOptSetDistances = "0.2.9"
-ParametricOptInterface = "0.15.1"
+ParametricOptInterface = "=0.15.1"
 julia = "1.6"