Add latexmkrc

.latexmkrc

+$pdf_mode = 4;
+$pdf_previewer = 'open -a Skim';
+$pdflatex = 'pdflatex -halt-on-error -interaction=nonstopmode -synctex=1 %O %S';
+$out_dir = 'build';
+$postscript_mode = $dvi_mode = 0;
+@generated_exts = (@generated_exts, 'synctex.gz');