diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d6d22b6..78afcb8 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -20,6 +20,9 @@ jobs:
     - name: Build library package
       run: yarn build:lib --prod
 
+    - name: Downlevel .d.ts files for TypeScript <3.7
+      run: yarn build:downlevel-dts
+
     - name: Copy readme and license files
       run: yarn build:copy-files
 
diff --git a/package.json b/package.json
index 9a86e92..6a63e74 100644
--- a/package.json
+++ b/package.json
@@ -13,6 +13,7 @@
     "build:lib": "ng build ngx-sweetalert2",
     "build:demo": "ng build ngx-sweetalert2-demo",
     "build:copy-files": "cp README.md dist/ngx-sweetalert2 && cp LICENSE.txt dist/ngx-sweetalert2",
+    "build:downlevel-dts": "downlevel-dts dist/ngx-sweetalert2 dist/ngx-sweetalert2/dts-ts3.4",
     "test": "yarn ngcc && run-p test:*",
     "test:lib": "ng test ngx-sweetalert2",
     "test:demo": "ng test ngx-sweetalert2-demo",
@@ -47,6 +48,7 @@
     "@types/jasminewd2": "~2.0.8",
     "@types/node": "^13.7.1",
     "codelyzer": "^5.1.2",
+    "downlevel-dts": "^0.4.0",
     "jasmine-core": "~3.5.0",
     "jasmine-spec-reporter": "~4.2.1",
     "karma": "~4.4.1",
diff --git a/projects/ngx-sweetalert2/package.json b/projects/ngx-sweetalert2/package.json
index 161a6e3..91c6bdb 100644
--- a/projects/ngx-sweetalert2/package.json
+++ b/projects/ngx-sweetalert2/package.json
@@ -9,5 +9,8 @@
     "@angular/common": ">=8.0.0",
     "@angular/core": ">=8.0.0",
     "sweetalert2": "^9.7.0"
+  },
+  "typesVersions": {
+    "<3.7": { "*": ["dts-ts3.4/sweetalert2-ngx-sweetalert2.d.ts"] }
   }
 }
diff --git a/yarn.lock b/yarn.lock
index 70aca38..95655a0 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3697,6 +3697,14 @@ dotenv@^5.0.1:
   resolved "https://registry.yarnpkg.com/dotenv/-/dotenv-5.0.1.tgz#a5317459bd3d79ab88cff6e44057a6a3fbb1fcef"
   integrity sha512-4As8uPrjfwb7VXC+WnLCbXK7y+Ueb2B3zgNCePYfhxS1PYeaO1YTeplffTEcbfLhvFNGLAz90VvJs9yomG7bow==
 
+downlevel-dts@^0.4.0:
+  version "0.4.0"
+  resolved "https://registry.yarnpkg.com/downlevel-dts/-/downlevel-dts-0.4.0.tgz#43f9f649c8b137373d76b4ee396d5a0227c10ddb"
+  integrity sha512-nh5vM3n2pRhPwZqh0iWo5gpItPAYEGEWw9yd0YpI+lO60B7A3A6iJlxDbt7kKVNbqBXKsptL+jwE/Yg5Go66WQ==
+  dependencies:
+    shelljs "^0.8.3"
+    typescript "^3.8.0-dev.20200111"
+
 duplexer2@~0.1.0:
   version "0.1.4"
   resolved "https://registry.yarnpkg.com/duplexer2/-/duplexer2-0.1.4.tgz#8b12dab878c0d69e3e7891051662a32fc6bddcc1"
@@ -4600,7 +4608,7 @@ glob@7.1.5:
     once "^1.3.0"
     path-is-absolute "^1.0.0"
 
-glob@^7.0.3, glob@^7.1.1, glob@^7.1.2, glob@^7.1.3, glob@^7.1.4:
+glob@^7.0.0, glob@^7.0.3, glob@^7.1.1, glob@^7.1.2, glob@^7.1.3, glob@^7.1.4:
   version "7.1.6"
   resolved "https://registry.yarnpkg.com/glob/-/glob-7.1.6.tgz#141f33b81a7c2492e125594307480c46679278a6"
   integrity sha512-LwaxwyZ72Lk7vZINtNNrywX0ZuLyStrdDtabefZKAY5ZGJhVtgdznluResxNmPitE0SAO+O26sWTHeKSI2wMBA==
@@ -5214,6 +5222,11 @@ internal-ip@^4.3.0:
     default-gateway "^4.2.0"
     ipaddr.js "^1.9.0"
 
+interpret@^1.0.0:
+  version "1.2.0"
+  resolved "https://registry.yarnpkg.com/interpret/-/interpret-1.2.0.tgz#d5061a6224be58e8083985f5014d844359576296"
+  integrity sha512-mT34yGKMNceBQUoVn7iCDKDntA7SC6gycMAWzGx1z/CMCTV7b2AAtXlo3nRyHZ1FelRkQbQjprHSYGwzLtkVbw==
+
 into-stream@^5.0.0:
   version "5.1.1"
   resolved "https://registry.yarnpkg.com/into-stream/-/into-stream-5.1.1.tgz#f9a20a348a11f3c13face22763f2d02e127f4db8"
@@ -8802,6 +8815,13 @@ readdirp@~3.3.0:
   dependencies:
     picomatch "^2.0.7"
 
+rechoir@^0.6.2:
+  version "0.6.2"
+  resolved "https://registry.yarnpkg.com/rechoir/-/rechoir-0.6.2.tgz#85204b54dba82d5742e28c96756ef43af50e3384"
+  integrity sha1-hSBLVNuoLVdC4oyWdW70OvUOM4Q=
+  dependencies:
+    resolve "^1.1.6"
+
 redent@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/redent/-/redent-2.0.0.tgz#c1b2007b42d57eb1389079b3c8333639d5e1ccaa"
@@ -9025,7 +9045,7 @@ resolve-url@^0.2.1:
   resolved "https://registry.yarnpkg.com/resolve-url/-/resolve-url-0.2.1.tgz#2c637fe77c893afd2a663fe21aa9080068e2052a"
   integrity sha1-LGN/53yJOv0qZj/iGqkIAGjiBSo=
 
-resolve@^1.1.7, resolve@^1.10.0, resolve@^1.11.0, resolve@^1.14.2, resolve@^1.3.2:
+resolve@^1.1.6, resolve@^1.1.7, resolve@^1.10.0, resolve@^1.11.0, resolve@^1.14.2, resolve@^1.3.2:
   version "1.15.1"
   resolved "https://registry.yarnpkg.com/resolve/-/resolve-1.15.1.tgz#27bdcdeffeaf2d6244b95bb0f9f4b4653451f3e8"
   integrity sha512-84oo6ZTtoTUpjgNEr5SJyzQhzL72gaRodsSfyxC/AXRvwu0Yse9H8eF9IpGo7b8YetZhlI6v7ZQ6bKBFV/6S7w==
@@ -9464,6 +9484,15 @@ shell-quote@^1.6.1:
   resolved "https://registry.yarnpkg.com/shell-quote/-/shell-quote-1.7.2.tgz#67a7d02c76c9da24f99d20808fcaded0e0e04be2"
   integrity sha512-mRz/m/JVscCrkMyPqHc/bczi3OQHkLTqXHEFu0zDhK/qfv3UcOA4SVmRCLmos4bhjr9ekVQubj/R7waKapmiQg==
 
+shelljs@^0.8.3:
+  version "0.8.3"
+  resolved "https://registry.yarnpkg.com/shelljs/-/shelljs-0.8.3.tgz#a7f3319520ebf09ee81275b2368adb286659b097"
+  integrity sha512-fc0BKlAWiLpwZljmOvAOTE/gXawtCoNrP5oaY7KIaQbbyHeQVg01pSEuEGvGh3HEdBU4baCD7wQBwADmM/7f7A==
+  dependencies:
+    glob "^7.0.0"
+    interpret "^1.0.0"
+    rechoir "^0.6.2"
+
 signal-exit@^3.0.0, signal-exit@^3.0.2:
   version "3.0.2"
   resolved "https://registry.yarnpkg.com/signal-exit/-/signal-exit-3.0.2.tgz#b5fdc08f1287ea1178628e415e25132b73646c6d"
@@ -10489,6 +10518,11 @@ typescript@3.6.4:
   resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.6.4.tgz#b18752bb3792bc1a0281335f7f6ebf1bbfc5b91d"
   integrity sha512-unoCll1+l+YK4i4F8f22TaNVPRHcD9PA3yCuZ8g5e0qGqlVlJ/8FSateOLLSagn+Yg5+ZwuPkL8LFUc0Jcvksg==
 
+typescript@^3.8.0-dev.20200111:
+  version "3.8.0-dev.20200211"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.8.0-dev.20200211.tgz#8723bc40da40e737b01977ba543af69d7a545d94"
+  integrity sha512-1LnADJbATvC2XSPcn7NwrhidLA03jXUx1x1ZfPNaceC8SCe5KtZwihzMe7PPmP5Sy2JiXD0pYp/X4MVogV57qQ==
+
 typescript@~3.7.5:
   version "3.7.5"
   resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.7.5.tgz#0692e21f65fd4108b9330238aac11dd2e177a1ae"