diff --git a/packages/squiggle-lang/package.json b/packages/squiggle-lang/package.json
index 97b710b6..6cbb4906 100644
--- a/packages/squiggle-lang/package.json
+++ b/packages/squiggle-lang/package.json
@@ -38,7 +38,7 @@
     "rescript": "^9.1.4",
     "jstat": "^1.9.5",
     "pdfast": "^0.2.0",
-    "mathjs": "^10.5.0"
+    "mathjs": "10.5.0"
   },
   "devDependencies": {
     "bisect_ppx": "^2.7.1",
diff --git a/packages/squiggle-lang/tsconfig.json b/packages/squiggle-lang/tsconfig.json
index ca34ebec..7a610d10 100644
--- a/packages/squiggle-lang/tsconfig.json
+++ b/packages/squiggle-lang/tsconfig.json
@@ -11,8 +11,7 @@
     "outDir": "./dist",
     "declarationDir": "./dist",
     "declaration": true,
-    "composite": true,
-    "skipLibCheck": true
+    "composite": true
   },
   "target": "ES6",
   "include": ["src/**/*"],