diff --git a/Project.toml b/Project.toml
index 04a4331..98c6cd8 100644
--- a/Project.toml
+++ b/Project.toml
@@ -32,6 +32,7 @@ BoundaryIntegralEquationsMeshesExt = "Meshes"
 [compat]
 Aqua = "0.8"
 DelimitedFiles = "1"
+FMM3D = "1"
 FastGaussQuadrature = "0.4, 0.5, 1"
 FileIO = "1"
 ForwardDiff = "0.10"