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+# Writing Makefiles
+
+## Pattern rules
+
+In prerequesite, use exactly one `%`. Can then be used in requirements. E.g.
+
+    %.o: %.c
+        # compile .c file to .o
+
+Details: <https://www.gnu.org/software/make/manual/html_node/Pattern-Rules.html>
+
+## Automatic variables
+
+* `$@`: current target
+* `$<`: first prerequisite
+* `$^`: all prerequisites, separated by spaces
+* `$(@F)`: file-within-directory part of target path
+
+More: <https://www.gnu.org/software/make/manual/html_node/Automatic-Variables.html>
+
+## Text functions
+
+* `$(var:suffix=replacement)`, syntax sugar for
+  `$(patsubst %suffix, $replacement, $(var))`
+
+More: <https://www.gnu.org/software/make/manual/html_node/Text-Functions.html>
+
+## Quiet commands
+
+By default, `make` prints the command being run. Prepend `@` to silence this.