diff --git a/package.json b/package.json
index f21e4fb..70f77cd 100644
--- a/package.json
+++ b/package.json
@@ -26,7 +26,7 @@
     "remark-html": "^9.0.0",
     "styled-components": "^4.1.3",
     "toml": "^3.0.0",
-    "typescript": "^4.0.3",
+    "typescript": "^3.9.7",
     "verror": "^1.10.0"
   },
   "scripts": {
diff --git a/yarn.lock b/yarn.lock
index 7c5bea4..6712579 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -12576,10 +12576,10 @@ typedarray@^0.0.6:
   resolved "https://registry.yarnpkg.com/typedarray/-/typedarray-0.0.6.tgz#867ac74e3864187b1d3d47d996a78ec5c8830777"
   integrity sha1-hnrHTjhkGHsdPUfZlqeOxciDB3c=
 
-typescript@^4.0.3:
-  version "4.0.3"
-  resolved "https://registry.yarnpkg.com/typescript/-/typescript-4.0.3.tgz#153bbd468ef07725c1df9c77e8b453f8d36abba5"
-  integrity sha512-tEu6DGxGgRJPb/mVPIZ48e69xCn2yRmCgYmDugAVwmJ6o+0u1RI18eO7E7WBTLYLaEVVOhwQmcdhQHweux/WPg==
+typescript@^3.9.7:
+  version "3.9.7"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.9.7.tgz#98d600a5ebdc38f40cb277522f12dc800e9e25fa"
+  integrity sha512-BLbiRkiBzAwsjut4x/dsibSTB6yWpwT5qWmC2OfuCg3GgVQCSgMs4vEctYPhsaGtd0AeuuHMkjZ2h2WG8MSzRw==
 
 uc.micro@^1.0.1, uc.micro@^1.0.5:
   version "1.0.6"