diff --git a/https-tls/openssl/README.md b/https-tls/openssl/README.md
index 985726a..05132f5 100644
--- a/https-tls/openssl/README.md
+++ b/https-tls/openssl/README.md
@@ -13,7 +13,7 @@ mkcert -install
 If you want to generate your own private key/certificate pair, then run:
 
 ```sh
-mkcert 127.0.0.1 localhost
+mkcert -key-file key.pem -cert-file cert.pem 127.0.0.1 localhost
 ```
 
 A new `key.pem` and `cert.pem` will be saved to the current directory. You will then need to modify `main.rs` where indicated.
diff --git a/https-tls/openssl/src/main.rs b/https-tls/openssl/src/main.rs
index 9b12d45..d3b604c 100644
--- a/https-tls/openssl/src/main.rs
+++ b/https-tls/openssl/src/main.rs
@@ -31,7 +31,9 @@ async fn main() -> io::Result<()> {
 
     // set the unencrypted private key
     // (uncomment if you generate your own key+cert with `mkcert`, and also remove the statement above)
-    // builder.set_private_key_file("key.pem").unwrap();
+    // builder
+    //     .set_private_key_file("key.pem", openssl::ssl::SslFiletype::PEM)
+    //     .unwrap();
 
     // set the certificate chain file location
     builder.set_certificate_chain_file("cert.pem").unwrap();