diff --git a/main.go b/main.go
index 5a835ba..eb4e0c5 100644
--- a/main.go
+++ b/main.go
@@ -5,8 +5,10 @@ import (
 	"fmt"
 	"io"
 	"log"
+	"mime"
 	"net/http"
 	"os"
+	"path"
 	"strings"
 
 	"git.mills.io/prologic/pages-server/gitea"
@@ -41,6 +43,10 @@ func (h *GiteaHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	extension := path.Ext(r.URL.Path)
+	mimeType := mime.TypeByExtension(extension)
+	w.Header().Add("content-type", mimeType)
+
 	if _, err := io.Copy(w, f); err != nil {
 		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
 	}