diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..6896ef6
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/config.mk
diff --git a/Makefile b/Makefile
index fee26db..2d41dcc 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,9 @@
+include: config.mk
+
 .PHONY: serve test clean instantiate
 
-JULIA_CMD = julia --color=yes --startup-file=no
+JULIA ?= julia
+JULIA_CMD ?= $(JULIA) --color=yes --startup-file=no
 
 serve: instantiate
 	bin/serve
@@ -13,3 +16,6 @@ clean:
 
 instantiate:
 	$(JULIA_CMD) -e 'using Pkg; Pkg.activate("."); Pkg.instantiate()'
+
+config.mk:
+	ln -s default-config.mk $@
diff --git a/default-config.mk b/default-config.mk
new file mode 100644
index 0000000..53f471b
--- /dev/null
+++ b/default-config.mk
@@ -0,0 +1 @@
+JULIA = julia1.6