diff --git a/org.kde.kcalc.json b/org.kde.kcalc.json
index 820bee6..1fec3fa 100644
--- a/org.kde.kcalc.json
+++ b/org.kde.kcalc.json
@@ -1,19 +1,29 @@
 {
     "id": "org.kde.kcalc",
     "branch": "master",
     "runtime": "org.kde.Platform",
     "runtime-version": "5.12",
     "sdk": "org.kde.Sdk",
     "command": "kcalc",
     "tags": ["nightly"],
     "desktop-file-name-suffix": " (Nightly)",
     "finish-args": ["--share=ipc", "--socket=x11", "--socket=wayland", "--filesystem=host" ],
 
     "modules": [
+        {
+            "name": "mpfr",
+            "sources": [
+                {
+                    "type": "archive",
+                    "url": "https://www.mpfr.org/mpfr-current/mpfr-4.0.2.tar.xz",
+                    "sha256": "1d3be708604eae0e42d578ba93b390c2a145f17743a744d8f3f8c2ad5855a38a"
+                }
+            ]
+        },
         {
             "name": "kcalc",
             "buildsystem": "cmake-ninja",
             "sources": [ { "type": "git", "url": "git://anongit.kde.org/kcalc.git" } ]
         }
     ]
 }