Add Crystal-related makefile configuration.

crystal/makefile

@@ -0,0 +1,29 @@
+# The following shows how to use a library that is not installed.
+# Usage example: make LIBPATH=/tmp/libipc/zig-out/lib/ build run
+
+LIBPATH ?=
+LD_LIBRARY_PATH=LD_LIBRARY_PATH=$(LIBPATH)
+CRYSTAL_LIBRARY_PATH=CRYSTAL_LIBRARY_PATH=$(LIBPATH)
+CRYSTAL_BUILD_OPTIONS ?=
+CRYSTAL_BUILD_OPTIONS += $(CRYSTAL_STATIC_BUILD)
+
+LIBIPC_RUNDIR ?= /tmp/libipc-run
+
+all: build
+build: build-pongd build-pong
+run: run-pongd
+
+include ../mk/makefile.utils
+
+build-pongd:
+	$(CRYSTAL_LIBRARY_PATH) shards build pongd $(CRYSTAL_BUILD_OPTIONS)
+
+run-pongd:
+	rm $(LIBIPC_RUNDIR)/pong 2>/dev/null || true
+	$(LD_LIBRARY_PATH) ./bin/pongd
+
+build-pong:
+	$(CRYSTAL_LIBRARY_PATH) shards build pong $(CRYSTAL_BUILD_OPTIONS)
+
+run-pong:
+	$(LD_LIBRARY_PATH) ./bin/pong

mk/makefile.static-build

@@ -1,5 +1,6 @@
 ifdef STATIC
 STATIC_BUILD ?= -static
+CRYSTAL_STATIC_BUILD ?= --static
 endif
 
 # For interactive completion in the shell.