diff --git a/runtimes/assemblyscript/dune b/runtimes/assemblyscript/dune
index 78757fce..2e4929e5 100644
--- a/runtimes/assemblyscript/dune
+++ b/runtimes/assemblyscript/dune
@@ -3,6 +3,8 @@
   (public_name coq-qcert.runtime.assemblyscript)
   (libraries wasm))
 
+(dirs :standard \ node_modules) ;; do not copy node_modules to _build
+
 (rule ; not evaluated for package release (-p flag)
   (target runtime.wasm)
   (deps