diff --git a/mkespfs.py b/mkespfs.py
index 6f6fbe9..cd4f5a0 100755
--- a/mkespfs.py
+++ b/mkespfs.py
@@ -18,7 +18,7 @@
 # 	int32_t magic;
 # 	int8_t flags;
 # 	int8_t compression;
-# 	int16_t nameLen; // including padding!
+# 	int16_t nameLen; // name must be null-terminated and NameLen includes padding!
 # 	int32_t fileLenComp;
 # 	int32_t fileLenDecomp;
 # } __attribute__((packed)) EspFsHeader;
@@ -34,25 +34,23 @@ def mkespfs(dir, outbuf):
     FL_GZIP = 2 # gzipped file flag
     FL_LAST = 1 # last entry file flag
 
-    f_html = list(Path(dir).rglob('*')) #.html'))
-    f_css = list(Path(dir).rglob('*.css'))
-    f_js = list(Path(dir).rglob('*.js'))
-    f_img = list(Path(dir).rglob('*.ico')) + list(Path(dir).rglob('*.png'))
-    f_all = f_html + f_css + f_js + f_img
     sz = 0
-
-    for fn in f_all:
+    for fn in Path(dir).rglob('*.*'):
         if not fn.is_file(): continue
-        out_path = fn.relative_to(dir).as_posix().encode('ascii')
+        out_path = fn.relative_to(dir).as_posix().encode('ascii') + b'\000'
         while len(out_path) & 3 != 0: out_path += b'\000'
         info = fn.stat()
         data_un = fn.read_bytes()
         data_comp = gzip.compress(data_un)
+        flag = FL_GZIP
+        if len(data_un) <= len(data_comp):
+            data_comp = data_un
+            flag = 0
 
         print("Processing {} -> {}[{}], {}->{} bytes".format(fn, out_path, len(out_path), info.st_size,
             len(data_comp)), file=stderr)
 
-        header = struct.pack('<IBBHII', MAGIC, FL_GZIP, 0, len(out_path), len(data_comp), info.st_size)
+        header = struct.pack('<IBBHII', MAGIC, flag, 0, len(out_path), len(data_comp), info.st_size)
         outbuf.write(header)
         sz += len(header)
         outbuf.write(out_path)
diff --git a/pio-genespfs.py b/pio-genespfs.py
index 737653d..dc9b94f 100644
--- a/pio-genespfs.py
+++ b/pio-genespfs.py
@@ -7,13 +7,43 @@ Import("env")
 from mkespfs import mkespfs
 from io import BytesIO
 from pathlib import Path
+import shutil
 
 dir = "html"
+hdr = "head-"
+temp = "temp-espfs"
 espfile = "src/espfs_img.c"
 
+# create empty temporary dir to create fs image
+shutil.rmtree(temp, ignore_errors=True)
+Path(temp).mkdir()
+
+# place all the files we want into a temp directory and prefix all .html with hdr
+f_html = list(Path(dir).rglob('*.html'))
+f_css = list(Path(dir).rglob('*.css'))
+f_js = list(Path(dir).rglob('*.js'))
+f_img = list(Path(dir).rglob('*.ico')) + list(Path(dir).rglob('*.png'))
+# simply copy most files
+for fn in f_css+f_js+f_img:
+    dst = Path(temp).joinpath(fn.relative_to(dir))
+    dst.parent.mkdir(exist_ok=True)
+    shutil.copyfile(fn, dst)
+# prepend shared header to html files
+for fn in f_html:
+    with open(Path(temp).joinpath(fn.relative_to(dir)), 'wb') as dst:
+        with open(Path(dir).joinpath(hdr), 'rb') as src:
+            shutil.copyfileobj(src, dst)
+        with open(fn, 'rb') as src:
+            shutil.copyfileobj(src, dst)
+
+# generate espfs image
 buf = BytesIO()
-espfsimg = mkespfs(dir, buf)
+espfsimg = mkespfs(temp, buf)
+
+# remove temp tree
+#shutil.rmtree(temp, ignore_errors=True)
 
+# write as C file
 fd = Path(espfile).open(mode='w')
 fd.write("unsigned char espfs_image[] ");
 fd.write("__attribute__((aligned(4))) ");