diff --git a/landing/package.json b/landing/package.json
index a46c0d43a..156dc73ff 100644
--- a/landing/package.json
+++ b/landing/package.json
@@ -13,7 +13,7 @@
   "dependencies": {
     "@astrojs/mdx": "^4.3.13",
     "@astrojs/vercel": "^9.0.2",
-    "@polar-sh/sdk": "^0.20.2",
+    "@polar-sh/sdk": "^0.43.0",
     "astro": "^5.17.1",
     "shepherd.js": "workspace:*"
   },
diff --git a/landing/src/actions/index.ts b/landing/src/actions/index.ts
index cda15fc72..c65dd66dd 100644
--- a/landing/src/actions/index.ts
+++ b/landing/src/actions/index.ts
@@ -17,8 +17,8 @@ export const server = {
       let result;
 
       try {
-        result = await polar.checkouts.custom.create({
-          productPriceId,
+        result = await polar.checkouts.create({
+          products: [productPriceId],
           successUrl: 'https://docs.shepherdjs.dev'
         });
       } catch (error) {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 77a7d3ac0..3f51c887e 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -100,8 +100,8 @@ importers:
         specifier: ^9.0.2
         version: 9.0.2(astro@5.17.1(@types/node@25.2.3)(@vercel/functions@2.2.13)(jiti@2.6.1)(lightningcss@1.30.2)(rollup@4.57.1)(terser@5.46.0)(typescript@5.9.3)(yaml@2.8.2))(encoding@0.1.13)(react@19.2.4)(rollup@4.57.1)(svelte@5.49.1)
       '@polar-sh/sdk':
-        specifier: ^0.20.2
-        version: 0.20.2(zod@3.25.76)
+        specifier: ^0.43.0
+        version: 0.43.0
       astro:
         specifier: ^5.17.1
         version: 5.17.1(@types/node@25.2.3)(@vercel/functions@2.2.13)(jiti@2.6.1)(lightningcss@1.30.2)(rollup@4.57.1)(terser@5.46.0)(typescript@5.9.3)(yaml@2.8.2)
@@ -2061,10 +2061,8 @@ packages:
     resolution: {integrity: sha512-c83qWb22rNRuB0UaVCI0uRPNRr8Z0FWnEIvT47jiHAmOIUHbBOg5XvV7pM5x+rKn9HRpjxquDbXYSXr3fAKFcw==}
     engines: {node: '>=12'}
 
-  '@polar-sh/sdk@0.20.2':
-    resolution: {integrity: sha512-Rrqt2jyg1VhO9Gfy3WpLF9bST5yxXGnNJ1a/vHw/N4CXWZNbafKjKVGI2f7t1emCosvzkT2BpIBf+b19CpUTiw==}
-    peerDependencies:
-      zod: '>= 3'
+  '@polar-sh/sdk@0.43.0':
+    resolution: {integrity: sha512-LvbnPAo5h9wAOpq8sgzonip0PtzU2UZydqxUpWeOdHjaBWNgV36dPRY3oQA7XD4EzRsUJhVl3hVc6sp1GnTX8g==}
 
   '@polka/url@1.0.0-next.29':
     resolution: {integrity: sha512-wwQAWhWSuHaag8c4q/KN/vCoeOJYshAIvMQwD4GpSb3OiZklFfvAgmj0VCBBImRpuF/aFgIRzllXlVX93Jevww==}
@@ -7830,6 +7828,9 @@ packages:
   zod@3.25.76:
     resolution: {integrity: sha512-gzUt/qt81nXsFGKIFcC3YnfEAx5NkunCfnDlvuBSSFS02bcXu4Lmea0AFIUwbLWxWPx3d9p8S5QoaujKcNQxcQ==}
 
+  zod@4.3.6:
+    resolution: {integrity: sha512-rftlrkhHZOcjDwkGlnUtZZkvaPHCsDATp4pGpuOOMDaTdDDXF91wuVDJoWoPsKX/3YPQ5fHuF3STjcYyKr+Qhg==}
+
   zwitch@2.0.4:
     resolution: {integrity: sha512-bXE4cR/kVZhKZX/RjPEflHaKVhUVl85noU3v6b8apfQEc1x4A+zBxjZ4lN8LqGd6WZ3dl98pY4o717VFmoPp+A==}
 
@@ -10380,10 +10381,10 @@ snapshots:
       '@pnpm/network.ca-file': 1.0.2
       config-chain: 1.1.13
 
-  '@polar-sh/sdk@0.20.2(zod@3.25.76)':
+  '@polar-sh/sdk@0.43.0':
     dependencies:
       standardwebhooks: 1.0.0
-      zod: 3.25.76
+      zod: 4.3.6
 
   '@polka/url@1.0.0-next.29': {}
 
@@ -17057,4 +17058,6 @@ snapshots:
 
   zod@3.25.76: {}
 
+  zod@4.3.6: {}
+
   zwitch@2.0.4: {}