diff --git a/spec/v1/config.spec.ts b/spec/v1/config.spec.ts
index 97d7b6faa..45d51f09c 100644
--- a/spec/v1/config.spec.ts
+++ b/spec/v1/config.spec.ts
@@ -21,53 +21,16 @@
 // SOFTWARE.
 
 import { expect } from "chai";
-import * as fs from "fs";
-import * as process from "process";
-import * as sinon from "sinon";
 
-import { config, resetCache } from "../../src/v1/config";
+import { config } from "../../src/v1/config";
 
 describe("config()", () => {
-  let readFileSync: sinon.SinonStub;
-  let cwdStub: sinon.SinonStub;
-
-  before(() => {
-    readFileSync = sinon.stub(fs, "readFileSync");
-    readFileSync.throws("Unexpected call");
-    cwdStub = sinon.stub(process, "cwd");
-    cwdStub.returns("/srv");
-  });
-
-  after(() => {
-    sinon.verifyAndRestore();
-  });
-
-  afterEach(() => {
-    resetCache();
-    delete process.env.FIREBASE_CONFIG;
-    delete process.env.CLOUD_RUNTIME_CONFIG;
-    delete process.env.K_CONFIGURATION;
-  });
-
-  it("will never load in GCFv2", () => {
-    const json = JSON.stringify({
-      foo: "bar",
-      firebase: {},
-    });
-    readFileSync.withArgs("/srv/.runtimeconfig.json").returns(Buffer.from(json));
-
-    process.env.K_CONFIGURATION = "my-service";
-    expect(config).to.throw(Error, /transition to using environment variables/);
-  });
-
-  it("loads config values from .runtimeconfig.json", () => {
-    const json = JSON.stringify({
-      foo: "bar",
-      firebase: {},
-    });
-    readFileSync.withArgs("/srv/.runtimeconfig.json").returns(Buffer.from(json));
-    const loaded = config();
-    expect(loaded).to.not.have.property("firebase");
-    expect(loaded).to.have.property("foo", "bar");
+  it("throws an error with migration guidance", () => {
+    expect(config).to.throw(
+      Error,
+      "functions.config() has been removed in firebase-functions v7. " +
+        "Migrate to environment parameters using the params module. " +
+        "Migration guide: https://firebase.google.com/docs/functions/config-env#migrate-config"
+    );
   });
 });
diff --git a/src/v1/config.ts b/src/v1/config.ts
index 2eafa3150..6b1522f33 100644
--- a/src/v1/config.ts
+++ b/src/v1/config.ts
@@ -20,63 +20,17 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
 
-import * as fs from "fs";
-import * as path from "path";
-
 export { firebaseConfig } from "../common/config";
 
-/** @internal */
-export let singleton: Record<string, any>;
-
-/** @internal */
-export function resetCache(): void {
-  singleton = undefined;
-}
-
 /**
- * Store and retrieve project configuration data such as third-party API
- * keys or other settings. You can set configuration values using the
- * Firebase CLI as described in
- * https://firebase.google.com/docs/functions/config-env.
- *
- * @deprecated Using functions.config() is discouraged. See https://firebase.google.com/docs/functions/config-env.
+ * @deprecated `functions.config()` has been removed in firebase-functions v7.
+ * Migrate to environment parameters using the `params` module immediately.
+ * Migration guide: https://firebase.google.com/docs/functions/config-env#migrate-config
  */
 export function config(): Record<string, any> {
-  // K_CONFIGURATION is only set in GCFv2
-  if (process.env.K_CONFIGURATION) {
-    throw new Error(
-      "functions.config() is no longer available in Cloud Functions for " +
-        "Firebase v2. Please see the latest documentation for information " +
-        "on how to transition to using environment variables"
-    );
-  }
-  if (typeof singleton === "undefined") {
-    init();
-  }
-  return singleton;
-}
-
-function init() {
-  try {
-    const parsed = JSON.parse(process.env.CLOUD_RUNTIME_CONFIG);
-    delete parsed.firebase;
-    singleton = parsed;
-    return;
-  } catch (e) {
-    // Do nothing
-  }
-
-  try {
-    const configPath =
-      process.env.CLOUD_RUNTIME_CONFIG || path.join(process.cwd(), ".runtimeconfig.json");
-    const contents = fs.readFileSync(configPath);
-    const parsed = JSON.parse(contents.toString("utf8"));
-    delete parsed.firebase;
-    singleton = parsed;
-    return;
-  } catch (e) {
-    // Do nothing
-  }
-
-  singleton = {};
+  throw new Error(
+    "functions.config() has been removed in firebase-functions v7. " +
+      "Migrate to environment parameters using the params module. " +
+      "Migration guide: https://firebase.google.com/docs/functions/config-env#migrate-config"
+  );
 }