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+Implementation notes
+====================
+
+Symlink attacks
+---------------
+
+MAT2 output predictable filenames (like yourfile.jpg.cleaned).
+This may lead to symlink attack. Please check if you OS prevent
+against them
+
+Archives handling
+-----------------
+
+MAT2 doesn't support archives yet, because we haven't found an usable way to ask the user
+what to do when a non-supported files are encountered.
+
+PDF handling
+------------
+
+MAT was doing some kind of rendering for PDF files, on a cairo surface, then
+printed it to a file. This kept the text selectable, but unfortunately, it
+didn't remove any *deep metadata*, like the ones in embedded pictures. This was
+on of the reason MAT was abandoned: the absence of satisfying solution to
+handle PDF. But apparently, people are ok with [pdf redact
+tools](https://github.com/firstlookmedia/pdf-redact-tools), that simply
+transform the PDF into images. So this is what's MAT2 is doing too.
+
+Images handling
+---------------
+
+When possible, images are handled like PDF: rendered on a surface, then saved
+to the filesystem. This ensures that every metadata is removed.
+