clean up test code

1 files changed, 1 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 7eae306..50f0376 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -18,6 +18,7 @@ libc = "0.2.44"
 nix = "0.17.0"
 rand = "0.7.3"
 indexmap = "1.4.0"
+futures = "0.3"
 
 [lib]
 name = "growthring"