Add Makefile

Makefile

@@ -0,0 +1,24 @@
+# Project variables.
+PROJECT_NAME = gnopls
+BUILD_FLAGS = -mod=readonly -ldflags='$(LD_FLAGS)'
+BUILD_FOLDER = ./build
+
+.PHONY: install build clean
+
+## install: Install the binary.
+install:
+	@echo Installing $(PROJECT_NAME)...
+	@go install $(BUILD_FLAGS) ./...
+	@gnopls version
+
+## build: Build the binary.
+build:
+	@echo Building $(PROJECT_NAME)...
+	@-mkdir -p $(BUILD_FOLDER) 2> /dev/null
+	@go build $(BUILD_FLAGS) -o $(BUILD_FOLDER) ./...
+
+## clean: Remove build dir. Also runs `go clean`.
+clean:
+	@echo Cleaning build cache...
+	@-rm -rf $(BUILD_FOLDER) 2> /dev/null
+	@go clean ./...