diff --git a/package-lock.json b/package-lock.json
index ca33062..9ce6e08 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "setup-deno",
-  "version": "2.2.0",
+  "version": "2.3.0",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
diff --git a/src/installer.ts b/src/installer.ts
index 8100845..559b426 100644
--- a/src/installer.ts
+++ b/src/installer.ts
@@ -1,4 +1,4 @@
-import type { Version, Arch, Platform } from "./types";
+import type { Version, Arch, Platform, DenoVersions } from "./types";
 
 import * as os from "os";
 import * as path from "path";
@@ -38,6 +38,8 @@ import * as io from "@actions/io";
 import { v4 as uuidV4 } from "uuid";
 import { HttpClient } from "@actions/http-client";
 
+import * as deprecatedVersions from "./versions-before-0.34.0.json";
+
 function getDenoArch(version: Version): Arch {
   return version === "nightly"
     ? "x86_64"
@@ -131,19 +133,18 @@ async function queryLatestMatch(versionSpec: Version): Promise<string> {
 }
 
 export async function getAvailableVersions(): Promise<string[]> {
-  // a temporary workaround until a Release API is provided. (#11)
   const httpc = new HttpClient("setup-deno");
-  const body = await (
-    await httpc.get(
-      "https://raw.githubusercontent.com/denoland/deno/master/Releases.md"
+  const body = (
+    await httpc.getJson<DenoVersions>(
+      "https://raw.githubusercontent.com/denoland/deno_website2/master/versions.json"
     )
-  ).readBody();
-  const matches = body.matchAll(/### (v?\d+\.\d+\.\d+)/g);
+  ).result;
+
+  if (body === null) {
+    throw new Error("Unable to fetch Deno versions");
+  }
 
-  return [...matches]
-    .map((m) => m[1])
-    .filter((v) => v && v !== "v0.0.0")
-    .map((version) => (version.startsWith("v") ? version : "v" + version));
+  return [...Object.keys(body.cli_to_std), ...deprecatedVersions];
 }
 
 export function getDownloadUrl(version: Version): string {
diff --git a/src/types.ts b/src/types.ts
index dd5d4f4..0029864 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -17,3 +17,12 @@ export type ArchOld = "x64";
 export type Arch = "x86_64" | ArchOld;
 
 export type Version = LiteralUnion<"nightly", string>;
+
+/**
+ * https://raw.githubusercontent.com/denoland/deno_website2/master/versions.json
+ */
+export interface DenoVersions {
+  std: string[];
+  cli: string[];
+  cli_to_std: Record<string, string>;
+}
diff --git a/src/versions-before-0.34.0.json b/src/versions-before-0.34.0.json
new file mode 100644
index 0000000..3017275
--- /dev/null
+++ b/src/versions-before-0.34.0.json
@@ -0,0 +1,69 @@
+[
+  "v0.33.0",
+  "v0.32.0",
+  "v0.31.0",
+  "v0.30.0",
+  "v0.29.0",
+  "v0.28.1",
+  "v0.28.0",
+  "v0.27.0",
+  "v0.26.0",
+  "v0.25.0",
+  "v0.24.0",
+  "v0.23.0",
+  "v0.22.0",
+  "v0.21.0",
+  "v0.20.0",
+  "v0.19.0",
+  "v0.18.0",
+  "v0.17.0",
+  "v0.16.0",
+  "v0.15.0",
+  "v0.14.0",
+  "v0.13.0",
+  "v0.12.0",
+  "v0.11.0",
+  "v0.10.0",
+  "v0.9.0",
+  "v0.8.0",
+  "v0.7.0",
+  "v0.6.0",
+  "v0.5.0",
+  "v0.4.0",
+  "v0.3.10",
+  "v0.3.9",
+  "v0.3.8",
+  "v0.3.7",
+  "v0.3.6",
+  "v0.3.5",
+  "v0.3.4",
+  "v0.3.3",
+  "v0.3.2",
+  "v0.3.1",
+  "v0.3.0",
+  "v0.2.11",
+  "v0.2.10",
+  "v0.2.9",
+  "v0.2.8",
+  "v0.2.7",
+  "v0.2.6",
+  "v0.2.5",
+  "v0.2.4",
+  "v0.2.3",
+  "v0.2.2",
+  "v0.2.1",
+  "v0.2.0",
+  "v0.1.12",
+  "v0.1.11",
+  "v0.1.10",
+  "v0.1.9",
+  "v0.1.8",
+  "v0.1.7",
+  "v0.1.6",
+  "v0.1.5",
+  "v0.1.4",
+  "v0.1.3",
+  "v0.1.2",
+  "v0.1.1",
+  "v0.1.0"
+]
diff --git a/tsconfig.json b/tsconfig.json
index b9c6d80..30428bf 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -4,7 +4,8 @@
     "module": "CommonJS",
     "outDir": "./lib",
     "rootDir": "./src",
-    "strict": true
+    "strict": true,
+    "resolveJsonModule": true
   },
   "exclude": ["node_modules", "**/*.test.ts"]
 }