diff --git a/package-lock.json b/package-lock.json
index e33b092..0f4e3f2 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -15,7 +15,7 @@
         "format-microformat": "^0.11.1",
         "fulfills": "^2.1.0",
         "github-publish": "^3.0.0",
-        "js-yaml": "^3.12.1",
+        "js-yaml": "^4.0.0",
         "micropub-express": "^0.8.1"
       },
       "devDependencies": {
@@ -288,6 +288,19 @@
         "node": ">=8"
       }
     },
+    "node_modules/@istanbuljs/load-nyc-config/node_modules/js-yaml": {
+      "version": "3.14.1",
+      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.14.1.tgz",
+      "integrity": "sha512-okMH7OXXJ7YrN9Ok3/SXrnu4iX9yOk+25nqX4imS2npuvTYDmo/QEZoqwZkYaIDk3jVvBOTOIEgEhaLOynBS9g==",
+      "dev": true,
+      "dependencies": {
+        "argparse": "^1.0.7",
+        "esprima": "^4.0.0"
+      },
+      "bin": {
+        "js-yaml": "bin/js-yaml.js"
+      }
+    },
     "node_modules/@istanbuljs/load-nyc-config/node_modules/resolve-from": {
       "version": "5.0.0",
       "resolved": "https://registry.npmjs.org/resolve-from/-/resolve-from-5.0.0.tgz",
@@ -2289,6 +2302,19 @@
         "node": ">= 4"
       }
     },
+    "node_modules/eslint/node_modules/js-yaml": {
+      "version": "3.14.1",
+      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.14.1.tgz",
+      "integrity": "sha512-okMH7OXXJ7YrN9Ok3/SXrnu4iX9yOk+25nqX4imS2npuvTYDmo/QEZoqwZkYaIDk3jVvBOTOIEgEhaLOynBS9g==",
+      "dev": true,
+      "dependencies": {
+        "argparse": "^1.0.7",
+        "esprima": "^4.0.0"
+      },
+      "bin": {
+        "js-yaml": "bin/js-yaml.js"
+      }
+    },
     "node_modules/eslint/node_modules/ms": {
       "version": "2.1.2",
       "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.2.tgz",
@@ -2786,6 +2812,18 @@
         "node": ">=8.0.0"
       }
     },
+    "node_modules/format-microformat/node_modules/js-yaml": {
+      "version": "3.14.1",
+      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.14.1.tgz",
+      "integrity": "sha512-okMH7OXXJ7YrN9Ok3/SXrnu4iX9yOk+25nqX4imS2npuvTYDmo/QEZoqwZkYaIDk3jVvBOTOIEgEhaLOynBS9g==",
+      "dependencies": {
+        "argparse": "^1.0.7",
+        "esprima": "^4.0.0"
+      },
+      "bin": {
+        "js-yaml": "bin/js-yaml.js"
+      }
+    },
     "node_modules/forwarded": {
       "version": "0.1.2",
       "resolved": "https://registry.npmjs.org/forwarded/-/forwarded-0.1.2.tgz",
@@ -4192,18 +4230,21 @@
       "license": "MIT"
     },
     "node_modules/js-yaml": {
-      "version": "3.13.1",
-      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.13.1.tgz",
-      "integrity": "sha512-YfbcO7jXDdyj0DGxYVSlSeQNHbD7XPWvrVWeVUujrQEoZzWJIRrCPoyk6kL6IAjAG2IolMK4T0hNUe0HOUs5Jw==",
-      "license": "MIT",
+      "version": "4.1.0",
+      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-4.1.0.tgz",
+      "integrity": "sha512-wpxZs9NoxZaJESJGIZTyDEaYpl0FKSA+FB9aJiyemKhMwkxQg63h4T1KJgUGHpTqPDNRcmmYLugrRjJlBtWvRA==",
       "dependencies": {
-        "argparse": "^1.0.7",
-        "esprima": "^4.0.0"
+        "argparse": "^2.0.1"
       },
       "bin": {
         "js-yaml": "bin/js-yaml.js"
       }
     },
+    "node_modules/js-yaml/node_modules/argparse": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/argparse/-/argparse-2.0.1.tgz",
+      "integrity": "sha512-8+9WqebbFzpX9OR+Wa6O29asIogeRMzcGtAINdpMHHyAg10f05aSFVBbcEqGf/PXw1EjAZ+q2/bEBg3DvurK3Q=="
+    },
     "node_modules/jsdoctypeparser": {
       "version": "6.1.0",
       "resolved": "https://registry.npmjs.org/jsdoctypeparser/-/jsdoctypeparser-6.1.0.tgz",
@@ -4938,6 +4979,19 @@
         "node": "*"
       }
     },
+    "node_modules/mocha/node_modules/js-yaml": {
+      "version": "3.13.1",
+      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.13.1.tgz",
+      "integrity": "sha512-YfbcO7jXDdyj0DGxYVSlSeQNHbD7XPWvrVWeVUujrQEoZzWJIRrCPoyk6kL6IAjAG2IolMK4T0hNUe0HOUs5Jw==",
+      "dev": true,
+      "dependencies": {
+        "argparse": "^1.0.7",
+        "esprima": "^4.0.0"
+      },
+      "bin": {
+        "js-yaml": "bin/js-yaml.js"
+      }
+    },
     "node_modules/mocha/node_modules/locate-path": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/locate-path/-/locate-path-3.0.0.tgz",
@@ -5456,6 +5510,19 @@
         "node": ">=8"
       }
     },
+    "node_modules/nyc/node_modules/js-yaml": {
+      "version": "3.14.1",
+      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.14.1.tgz",
+      "integrity": "sha512-okMH7OXXJ7YrN9Ok3/SXrnu4iX9yOk+25nqX4imS2npuvTYDmo/QEZoqwZkYaIDk3jVvBOTOIEgEhaLOynBS9g==",
+      "dev": true,
+      "dependencies": {
+        "argparse": "^1.0.7",
+        "esprima": "^4.0.0"
+      },
+      "bin": {
+        "js-yaml": "bin/js-yaml.js"
+      }
+    },
     "node_modules/nyc/node_modules/resolve-from": {
       "version": "5.0.0",
       "resolved": "https://registry.npmjs.org/resolve-from/-/resolve-from-5.0.0.tgz",
diff --git a/package.json b/package.json
index 5010a68..f323988 100644
--- a/package.json
+++ b/package.json
@@ -61,7 +61,7 @@
     "format-microformat": "^0.11.1",
     "fulfills": "^2.1.0",
     "github-publish": "^3.0.0",
-    "js-yaml": "^3.12.1",
+    "js-yaml": "^4.0.0",
     "micropub-express": "^0.8.1"
   }
 }