diff --git a/package-lock.json b/package-lock.json
index d3eb544d..be9d1af4 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -7,7 +7,8 @@
       "hasInstallScript": true,
       "license": "MIT",
       "dependencies": {
-        "es-module-shims": "^0.4.6"
+        "es-module-shims": "^0.4.6",
+        "yarn": "^1.22.18"
       },
       "devDependencies": {
         "@11ty/eleventy-plugin-rss": "1.0.7",
@@ -8879,11 +8880,10 @@
       }
     },
     "node_modules/thenify": {
-      "version": "3.3.0",
-      "resolved": "https://registry.npmjs.org/thenify/-/thenify-3.3.0.tgz",
-      "integrity": "sha1-5p44obq+lpsBCCB5eLn2K4hgSDk=",
+      "version": "3.3.1",
+      "resolved": "https://registry.npmjs.org/thenify/-/thenify-3.3.1.tgz",
+      "integrity": "sha512-RVZSIV5IG10Hk3enotrhvz0T9em6cyHBLkH/YAZuKqd8hRkKhSfCGIcP2KUY0EPxndzANBmNllzWPwak+bheSw==",
       "dev": true,
-      "license": "MIT",
       "dependencies": {
         "any-promise": "^1.0.0"
       }
@@ -9707,6 +9707,19 @@
         "camelcase": "^3.0.0"
       }
     },
+    "node_modules/yarn": {
+      "version": "1.22.19",
+      "resolved": "https://registry.npmjs.org/yarn/-/yarn-1.22.19.tgz",
+      "integrity": "sha512-/0V5q0WbslqnwP91tirOvldvYISzaqhClxzyUKXYxs07yUILIs5jx/k6CFe8bvKSkds5w+eiOqta39Wk3WxdcQ==",
+      "hasInstallScript": true,
+      "bin": {
+        "yarn": "bin/yarn.js",
+        "yarnpkg": "bin/yarn.js"
+      },
+      "engines": {
+        "node": ">=4.0.0"
+      }
+    },
     "node_modules/yeast": {
       "version": "0.1.2",
       "resolved": "https://registry.npmjs.org/yeast/-/yeast-0.1.2.tgz",
@@ -16530,9 +16543,9 @@
       }
     },
     "thenify": {
-      "version": "3.3.0",
-      "resolved": "https://registry.npmjs.org/thenify/-/thenify-3.3.0.tgz",
-      "integrity": "sha1-5p44obq+lpsBCCB5eLn2K4hgSDk=",
+      "version": "3.3.1",
+      "resolved": "https://registry.npmjs.org/thenify/-/thenify-3.3.1.tgz",
+      "integrity": "sha512-RVZSIV5IG10Hk3enotrhvz0T9em6cyHBLkH/YAZuKqd8hRkKhSfCGIcP2KUY0EPxndzANBmNllzWPwak+bheSw==",
       "dev": true,
       "requires": {
         "any-promise": "^1.0.0"
@@ -17143,6 +17156,11 @@
         "camelcase": "^3.0.0"
       }
     },
+    "yarn": {
+      "version": "1.22.19",
+      "resolved": "https://registry.npmjs.org/yarn/-/yarn-1.22.19.tgz",
+      "integrity": "sha512-/0V5q0WbslqnwP91tirOvldvYISzaqhClxzyUKXYxs07yUILIs5jx/k6CFe8bvKSkds5w+eiOqta39Wk3WxdcQ=="
+    },
     "yeast": {
       "version": "0.1.2",
       "resolved": "https://registry.npmjs.org/yeast/-/yeast-0.1.2.tgz",
diff --git a/yarn.lock b/yarn.lock
index 5ef3d72d..ef723ed4 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1119,8 +1119,8 @@ any-promise@^0.1.0:
 
 any-promise@^1.0.0, any-promise@^1.1.0:
   version "1.3.0"
-  resolved "https://registry.npmjs.org/any-promise/-/any-promise-1.3.0.tgz"
-  integrity sha1-q8av7tzqUugJzcA3au0845Y10X8=
+  resolved "https://registry.yarnpkg.com/any-promise/-/any-promise-1.3.0.tgz#abc6afeedcea52e809cdc0376aed3ce39635d17f"
+  integrity sha512-7UvmKalWRt1wgjL1RrGxoSJW/0QZFIegpeGvZG9kjp8vrRu55XTHbwnqq2GpXm9uLbcuhxm3IqX9OB4MZR1b2A==
 
 anymatch@^2.0.0:
   version "2.0.0"
@@ -5085,9 +5085,9 @@ thenify-all@^1.0.0:
     thenify ">= 3.1.0 < 4"
 
 "thenify@>= 3.1.0 < 4":
-  version "3.3.0"
-  resolved "https://registry.npmjs.org/thenify/-/thenify-3.3.0.tgz"
-  integrity sha1-5p44obq+lpsBCCB5eLn2K4hgSDk=
+  version "3.3.1"
+  resolved "https://registry.yarnpkg.com/thenify/-/thenify-3.3.1.tgz#8932e686a4066038a016dd9e2ca46add9838a95f"
+  integrity sha512-RVZSIV5IG10Hk3enotrhvz0T9em6cyHBLkH/YAZuKqd8hRkKhSfCGIcP2KUY0EPxndzANBmNllzWPwak+bheSw==
   dependencies:
     any-promise "^1.0.0"