Add target to cross-compile for Linux (amd64)

Hint in readme on how to change built target platform.

Makefile

@@ -14,7 +14,7 @@ export PATH := $(BIN_DIR):$(PATH)
 
 export GOMODCACHE = $(LOCAL_DIR)/cache/go
 export GOTMPDIR = $(TMP_DIR)/go
-
+export GOBIN = $(BIN_DIR)
 
 
 default: clean install build run
@@ -39,6 +39,11 @@ $(BIN_DIR)/artifact.bin:
 		-o $(@) \
 		$(SRC_DIR)/*.go
 
+.PHONY: build-linux
+build-linux: export GOOS := linux
+build-linux: export GOARCH := amd64
+build-linux: $(BIN_DIR)/artifact.bin
+
 
 .PHONY: test
 .SILENT: test

README.md

@@ -2,7 +2,7 @@ Webservice
 ==========
 
 A Go-based simple web service meant to be the subject for any tutorial
-or even the project work.
+or maybe even the project work.
 
 
 __Prerequisites:__
@@ -10,11 +10,12 @@ __Prerequisites:__
 * Go toolchain (install via system package manager or [by hand](https://go.dev/doc/install))
 
 
-__Main interactions:__
+__Primary interactions:__
 
 1. Install dependencies: `go get -t ./...`
 2. Run locally: `go run .`
 3. Execute unit tests: `go test -race -v ./...`
 4. Build artifact: `go build -o ./artifact.bin ./*.go`
 
-For more details, please refer to the `Makefile`.
+To build for another platform, set `GOOS` and `GOARCH`. For more details,
+please refer to the `Makefile`.