update readme + accept modernize suggestion

README.md

@@ -4,6 +4,7 @@
 ![coverage](https://raw.githubusercontent.com/cyberbeast/httpcache/badges/.badges/main/coverage.svg)
 
 An HTTP transport for Go standard library's HTTP Client that caches HTTP Responses in a database to speed up subsequent requests. Currently supported:
+
 1. `sqlite`
 2. `postgres` (coming soon)
 
@@ -26,7 +27,7 @@ The implementation currently uses a very basic hashing mechanism to create a sig
 ## Todo
 
 - [x] Basic Cache Invalidation support
-- [ ] Add `postgres` as an alternative source
+- [x] Add `postgres` as an alternative source
 - [ ] Improve test coverage
 - [ ] Add `pgxpool` support for `postgres` source
 - [ ] Custom caching strategy based on HTTP response status codes

hash.go

@@ -33,7 +33,7 @@ func hash(headers http.Header) string {
 
 	var sb strings.Builder
 	for _, key := range keys {
-		sb.WriteString(fmt.Sprintf("%s:%s%s", key, headers.Get(key), delimiter))
+		fmt.Fprintf(&sb, "%s:%s%s", key, headers.Get(key), delimiter)
 	}
 
 	return sha256str([]byte(sb.String()))