diff --git a/Project.toml b/Project.toml
index 37771b3..30f346c 100644
--- a/Project.toml
+++ b/Project.toml
@@ -20,7 +20,7 @@ StarAlgebras = "0c0c59c1-dc5f-42e9-9a8b-b5dc384a6cd1"
 [compat]
 DataStructures = "0.18"
 DynamicPolynomials = "0.5,0.6"
-IntervalArithmetic = "0.20, 0.21, 0.22" # Needs v0.20 for Julia v1.6 support
+IntervalArithmetic = "0.20, 0.21, 0.22, 1.0" # Needs v0.20 for Julia v1.6 support
 JuMP = "1"
 MathOptInterface = "1"
 MultivariateBases = "0.2"