diff --git a/package.json b/package.json
--- a/package.json
+++ b/package.json
@@ -24,6 +24,7 @@
     "lit": "^2.2.2",
     "mocha": "^2.5.3",
     "n3": "^1.0.0-alpha",
+    "parse-prometheus-text-format": "^1.1.1",
     "pixi.js": "^4.7.3",
     "significant-rounding": "^2.0.0",
     "tinycolor2": "^1.4.1",