diff --git a/datastore.nimble b/datastore.nimble
index 1900f3d..473ad2e 100644
--- a/datastore.nimble
+++ b/datastore.nimble
@@ -8,7 +8,7 @@ license       = "Apache License 2.0 or MIT"
 
 requires "nim >= 1.2.0",
          "asynctest >= 0.4.3 & < 0.5.0",
-         "chronos",
+         "chronos#head", # FIXME change to Chronos >= 4.0.0 once it's out
          "questionable >= 0.10.3 & < 0.11.0",
          "sqlite3_abi",
          "stew",