diff --git a/.github/sync-repo-settings.yaml b/.github/sync-repo-settings.yaml
index 4a30a08e..1350faef 100644
--- a/.github/sync-repo-settings.yaml
+++ b/.github/sync-repo-settings.yaml
@@ -9,9 +9,9 @@ branchProtectionRules:
       - "ci/kokoro: System test"
       - docs
       - lint
-      - test (12)
       - test (14)
       - test (16)
+      - test (18)
       - cla/google
       - windows
       - OwlBot Post Processor
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 2377ffbe..3932645f 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node: [12, 14, 16]
+        node: [14, 16, 18]
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-node@v3
diff --git a/.kokoro/continuous/node12/common.cfg b/.kokoro/continuous/node12/common.cfg
deleted file mode 100644
index 8e9e508e..00000000
--- a/.kokoro/continuous/node12/common.cfg
+++ /dev/null
@@ -1,24 +0,0 @@
-# Format: //devtools/kokoro/config/proto/build.proto
-
-# Build logs will be here
-action {
-  define_artifacts {
-    regex: "**/*sponge_log.xml"
-  }
-}
-
-# Download trampoline resources.
-gfile_resources: "/bigstore/cloud-devrel-kokoro-resources/trampoline"
-
-# Use the trampoline script to run in docker.
-build_file: "google-auth-library-nodejs/.kokoro/trampoline_v2.sh"
-
-# Configure the docker image for kokoro-trampoline.
-env_vars: {
-    key: "TRAMPOLINE_IMAGE"
-    value: "gcr.io/cloud-devrel-kokoro-resources/node:12-user"
-}
-env_vars: {
-    key: "TRAMPOLINE_BUILD_FILE"
-    value: "github/google-auth-library-nodejs/.kokoro/test.sh"
-}
diff --git a/.kokoro/continuous/node12/lint.cfg b/.kokoro/continuous/node12/lint.cfg
deleted file mode 100644
index 49ffcd82..00000000
--- a/.kokoro/continuous/node12/lint.cfg
+++ /dev/null
@@ -1,4 +0,0 @@
-env_vars: {
-    key: "TRAMPOLINE_BUILD_FILE"
-    value: "github/google-auth-library-nodejs/.kokoro/lint.sh"
-}
diff --git a/.kokoro/continuous/node12/samples-test.cfg b/.kokoro/continuous/node12/samples-test.cfg
deleted file mode 100644
index 9571f5db..00000000
--- a/.kokoro/continuous/node12/samples-test.cfg
+++ /dev/null
@@ -1,12 +0,0 @@
-# Download resources for system tests (service account key, etc.)
-gfile_resources: "/bigstore/cloud-devrel-kokoro-resources/google-cloud-nodejs"
-
-env_vars: {
-    key: "TRAMPOLINE_BUILD_FILE"
-    value: "github/google-auth-library-nodejs/.kokoro/samples-test.sh"
-}
-
-env_vars: {
-  key: "SECRET_MANAGER_KEYS"
-  value: "long-door-651-kokoro-system-test-service-account"
-}
\ No newline at end of file
diff --git a/.kokoro/continuous/node12/system-test.cfg b/.kokoro/continuous/node12/system-test.cfg
deleted file mode 100644
index 83d64098..00000000
--- a/.kokoro/continuous/node12/system-test.cfg
+++ /dev/null
@@ -1,12 +0,0 @@
-# Download resources for system tests (service account key, etc.)
-gfile_resources: "/bigstore/cloud-devrel-kokoro-resources/google-cloud-nodejs"
-
-env_vars: {
-    key: "TRAMPOLINE_BUILD_FILE"
-    value: "github/google-auth-library-nodejs/.kokoro/system-test.sh"
-}
-
-env_vars: {
-  key: "SECRET_MANAGER_KEYS"
-  value: "long-door-651-kokoro-system-test-service-account"
-}
\ No newline at end of file
diff --git a/.kokoro/continuous/node12/test.cfg b/.kokoro/continuous/node12/test.cfg
deleted file mode 100644
index e69de29b..00000000
diff --git a/.kokoro/presubmit/node12/common.cfg b/.kokoro/presubmit/node12/common.cfg
deleted file mode 100644
index 8e9e508e..00000000
--- a/.kokoro/presubmit/node12/common.cfg
+++ /dev/null
@@ -1,24 +0,0 @@
-# Format: //devtools/kokoro/config/proto/build.proto
-
-# Build logs will be here
-action {
-  define_artifacts {
-    regex: "**/*sponge_log.xml"
-  }
-}
-
-# Download trampoline resources.
-gfile_resources: "/bigstore/cloud-devrel-kokoro-resources/trampoline"
-
-# Use the trampoline script to run in docker.
-build_file: "google-auth-library-nodejs/.kokoro/trampoline_v2.sh"
-
-# Configure the docker image for kokoro-trampoline.
-env_vars: {
-    key: "TRAMPOLINE_IMAGE"
-    value: "gcr.io/cloud-devrel-kokoro-resources/node:12-user"
-}
-env_vars: {
-    key: "TRAMPOLINE_BUILD_FILE"
-    value: "github/google-auth-library-nodejs/.kokoro/test.sh"
-}
diff --git a/.kokoro/presubmit/node12/samples-test.cfg b/.kokoro/presubmit/node12/samples-test.cfg
deleted file mode 100644
index 9571f5db..00000000
--- a/.kokoro/presubmit/node12/samples-test.cfg
+++ /dev/null
@@ -1,12 +0,0 @@
-# Download resources for system tests (service account key, etc.)
-gfile_resources: "/bigstore/cloud-devrel-kokoro-resources/google-cloud-nodejs"
-
-env_vars: {
-    key: "TRAMPOLINE_BUILD_FILE"
-    value: "github/google-auth-library-nodejs/.kokoro/samples-test.sh"
-}
-
-env_vars: {
-  key: "SECRET_MANAGER_KEYS"
-  value: "long-door-651-kokoro-system-test-service-account"
-}
\ No newline at end of file
diff --git a/.kokoro/presubmit/node12/system-test.cfg b/.kokoro/presubmit/node12/system-test.cfg
deleted file mode 100644
index 83d64098..00000000
--- a/.kokoro/presubmit/node12/system-test.cfg
+++ /dev/null
@@ -1,12 +0,0 @@
-# Download resources for system tests (service account key, etc.)
-gfile_resources: "/bigstore/cloud-devrel-kokoro-resources/google-cloud-nodejs"
-
-env_vars: {
-    key: "TRAMPOLINE_BUILD_FILE"
-    value: "github/google-auth-library-nodejs/.kokoro/system-test.sh"
-}
-
-env_vars: {
-  key: "SECRET_MANAGER_KEYS"
-  value: "long-door-651-kokoro-system-test-service-account"
-}
\ No newline at end of file
diff --git a/.kokoro/presubmit/node12/test.cfg b/.kokoro/presubmit/node12/test.cfg
deleted file mode 100644
index e69de29b..00000000
diff --git a/package.json b/package.json
index eb2846bb..9913fd54 100644
--- a/package.json
+++ b/package.json
@@ -4,7 +4,7 @@
   "author": "Google Inc.",
   "description": "Google APIs Authentication Client Library for Node.js",
   "engines": {
-    "node": ">=12"
+    "node": ">=14"
   },
   "main": "./build/src/index.js",
   "types": "./build/src/index.d.ts",
@@ -41,7 +41,7 @@
     "chai": "^4.2.0",
     "codecov": "^3.0.2",
     "execa": "^5.0.0",
-    "gts": "^3.1.0",
+    "gts": "^3.1.1",
     "is-docker": "^2.0.0",
     "karma": "^6.0.0",
     "karma-chrome-launcher": "^3.0.0",
@@ -60,7 +60,7 @@
     "puppeteer": "^20.0.0",
     "sinon": "^15.0.0",
     "ts-loader": "^8.0.0",
-    "typescript": "^4.6.3",
+    "typescript": "^5.1.6",
     "webpack": "^5.21.2",
     "webpack-cli": "^4.0.0"
   },
diff --git a/samples/package.json b/samples/package.json
index 74193cb3..1522da45 100644
--- a/samples/package.json
+++ b/samples/package.json
@@ -9,7 +9,7 @@
     "test": "mocha --timeout 60000"
   },
   "engines": {
-    "node": ">=12"
+    "node": ">=14"
   },
   "license": "Apache-2.0",
   "dependencies": {