diff --git a/package.json b/package.json
index 359ba1b..8ad068a 100644
--- a/package.json
+++ b/package.json
@@ -54,6 +54,7 @@
     "@babel/register": "7.13.8",
     "ava": "3.15.0",
     "babel-plugin-transform-remove-console": "6.9.4",
+    "babel-plugin-unassert": "3.0.1",
     "c8": "7.6.0",
     "coveralls": "3.1.0",
     "esdoc": "1.1.0",
diff --git a/yarn.lock b/yarn.lock
index 0784690..8913c1e 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1642,6 +1642,11 @@ babel-plugin-transform-remove-console@6.9.4:
   resolved "https://registry.yarnpkg.com/babel-plugin-transform-remove-console/-/babel-plugin-transform-remove-console-6.9.4.tgz#b980360c067384e24b357a588d807d3c83527780"
   integrity sha1-uYA2DAZzhOJLNXpYjYB9PINSd4A=
 
+babel-plugin-unassert@3.0.1:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/babel-plugin-unassert/-/babel-plugin-unassert-3.0.1.tgz#cba17c38249a0bb26a72eb3793e0b24e29fcb7cd"
+  integrity sha512-dJvXKECYExv+GGieSm6jNe1H+HRa6hH/qPZWOoUfAN+cO6GbnC9fCbwHeJs0XZ2UqcEtJLpJCMs8q0pUEMI0fw==
+
 babel-runtime@^6.22.0, babel-runtime@^6.26.0, babel-runtime@^6.9.0:
   version "6.26.0"
   resolved "https://registry.yarnpkg.com/babel-runtime/-/babel-runtime-6.26.0.tgz#965c7058668e82b55d7bfe04ff2337bc8b5647fe"