Adding a Makefile

Makefile

@@ -0,0 +1,36 @@
+MAKEFLAGS += --silent
+
+all: clean format test build
+
+## help: Prints a list of available build targets.
+help:
+	echo "Usage: make <OPTIONS> ... <TARGETS>"
+	echo ""
+	echo "Available targets are:"
+	echo ''
+	sed -n 's/^##//p' ${PWD}/Makefile | column -t -s ':' | sed -e 's/^/ /'
+	echo
+	echo "Targets run by default are: `sed -n 's/^all: //p' ./Makefile | sed -e 's/ /, /g' | sed -e 's/\(.*\), /\1, and /'`"
+
+## clean: Removes any previously created build artifacts.
+clean:
+	rm -f ./xk6
+	rm -f ./k6
+
+## build: Builds the 'xk6' binary.
+build:
+	go build -work ./cmd/xk6
+
+## format: Applies Go formatting to code.
+format:
+	go fmt ./...
+
+## test: Executes any unit tests.
+test:
+	go test -cover -race ./...
+
+## vendor: Pulls source for external dependencies.
+vendor:
+	go mod vendor
+
+.PHONY: build clean format help test vendor