diff --git a/std/compress/lzss/compress.go b/std/compress/lzss/compress.go
index 81cdb1bb6d..eb7c3fa4cb 100644
--- a/std/compress/lzss/compress.go
+++ b/std/compress/lzss/compress.go
@@ -50,7 +50,10 @@ func NewCompressor(dict []byte, level Level) (*Compressor, error) {
 		dictData: dict,
 	}
 	c.buf.Grow(maxInputSize)
-	c.dictIndex = suffixarray.New(c.dictData, c.dictSa[:len(c.dictData)])
+	if level != NoCompression {
+		// if we don't compress we don't need the dict.
+		c.dictIndex = suffixarray.New(c.dictData, c.dictSa[:len(c.dictData)])
+	}
 	c.level = level
 	return c, nil
 }