diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..f4fec7d
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,73 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1710146030,
+        "narHash": "sha256-SZ5L6eA7HJ/nmkzGG7/ISclqe6oZdOZTNoesiInkXPQ=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "b1d9ab70662946ef0850d488da1c9019f3a9752a",
+        "type": "github"
+      },
+      "original": {
+        "id": "flake-utils",
+        "type": "indirect"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1714314149,
+        "narHash": "sha256-yNAevSKF4krRWacmLUsLK7D7PlfuY3zF0lYnGYNi9vQ=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "cf8cc1201be8bc71b7cbbbdaf349b22f4f99c7ae",
+        "type": "github"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "type": "indirect"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs",
+        "systems": "systems_2"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
+    "systems_2": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "id": "systems",
+        "type": "indirect"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/server/certificates/certificates.go b/server/certificates/certificates.go
index a8b1c06..f48b03b 100644
--- a/server/certificates/certificates.go
+++ b/server/certificates/certificates.go
@@ -199,7 +199,6 @@ func (c *AcmeClient) retrieveCertFromDB(sni, mainDomainSuffix string, useDnsProv
 
 	// TODO: document & put into own function
 	if !strings.EqualFold(sni, mainDomainSuffix) {
-
 		// renew certificates 7 days before they expire
 		if tlsCertificate.Leaf.NotAfter.Before(time.Now().Add(7 * 24 * time.Hour)) {
 			// TODO: use ValidTill of custom cert struct