diff --git a/.gitignore b/.gitignore
index 66fd13c..180e910 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,3 +13,4 @@
 
 # Dependency directories (remove the comment below to include it)
 # vendor/
+.DS_Store
diff --git a/cmd/scanenv/main.go b/cmd/scanenv/main.go
index 57c714a..97f4d21 100644
--- a/cmd/scanenv/main.go
+++ b/cmd/scanenv/main.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"errors"
 	"fmt"
 	"os"
 
@@ -9,10 +10,13 @@ import (
 )
 
 func main() {
+
 	app := args.App{}
 	app = app.Import(scan.Args)
-	err := app.Parse()
-	if err != nil {
+	if err := app.Parse(); err != nil {
+		if errors.Is(err, args.ErrUsageRequested) {
+			return
+		}
 		panic(err)
 	}
 
diff --git a/go.mod b/go.mod
index fab4ce9..b2f6089 100644
--- a/go.mod
+++ b/go.mod
@@ -4,6 +4,6 @@ go 1.16
 
 require (
 	github.com/matryer/is v1.4.0
-	github.com/taybart/args v0.0.0-20210718035434-490aa1694337
+	github.com/taybart/args v0.0.2
 	github.com/taybart/log v1.6.2
 )
diff --git a/go.sum b/go.sum
index 50db5cb..a38b59c 100644
--- a/go.sum
+++ b/go.sum
@@ -1,8 +1,7 @@
 github.com/matryer/is v1.4.0 h1:sosSmIWwkYITGrxZ25ULNDeKiMNzFSr4V/eqBQP0PeE=
 github.com/matryer/is v1.4.0/go.mod h1:8I/i5uYgLzgsgEloJE1U6xx5HkBQpAZvepWuujKwMRU=
-github.com/taybart/args v0.0.0-20210718035434-490aa1694337 h1:hn2L5QAtWn4OD0faFFBMWStzVe5BQVW9gh4p/F3Ma7Y=
-github.com/taybart/args v0.0.0-20210718035434-490aa1694337/go.mod h1:l8CZDnKNf9iNMfX7UOSq7BbwpmwOLcJ7A6DehAP6A+g=
-github.com/taybart/log v1.4.1 h1:W33bTp9iviJxhohNXkU7Og7n63D2zKufP8hn2nO5Jfk=
-github.com/taybart/log v1.4.1/go.mod h1:zG3tAVOXRh0zQfyxs0dTqarj1hTKFOUWk/oKeiugmZA=
+github.com/taybart/args v0.0.2 h1:I2uGSfUse9lqoFy/1dC/kRuwZ/u83KKSosM3staYmAs=
+github.com/taybart/args v0.0.2/go.mod h1:aZ8Gg0AdpDyO3BjBfPEiwkIHu/gV/k1Iz4FDJtytGIw=
+github.com/taybart/log v1.5.1/go.mod h1:zG3tAVOXRh0zQfyxs0dTqarj1hTKFOUWk/oKeiugmZA=
 github.com/taybart/log v1.6.2 h1:loVHUm+sG4Xfz2LtXggSL5o8o58GwXWW4QWeYCyJpaY=
 github.com/taybart/log v1.6.2/go.mod h1:zG3tAVOXRh0zQfyxs0dTqarj1hTKFOUWk/oKeiugmZA=
diff --git a/scan/scan.go b/scan/scan.go
index baf6c0b..511bd70 100644
--- a/scan/scan.go
+++ b/scan/scan.go
@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"go/ast"
+	"go/build"
 	"io"
 	"os"
 	"path/filepath"
@@ -26,25 +27,26 @@ var (
 		Args: map[string]*args.Arg{
 			"files": {
 				Short: "f",
-				Long:  "files",
 				Help:  "Comma seperated files to check (./main.go,./util.go)",
 			},
 			"directory": {
 				Short: "d",
-				Long:  "directory",
 				Help:  "Scan directory",
 			},
 			"validate": {
 				Short: "v",
-				Long:  "validate",
 				Help:  "File to validate env config against",
 			},
 			"print": {
 				Short:   "p",
-				Long:    "print",
 				Help:    "Print contents in env file format, will add file tags above each env",
 				Default: false,
 			},
+			"tags": {
+				Short:   "t",
+				Help:    "Use go build tags",
+				Default: "",
+			},
 		},
 	}
 )
@@ -73,6 +75,16 @@ func Scan(app args.App) error {
 				return e
 			}
 			if re.Match([]byte(path)) {
+				// check if build tags apply
+				if app.Get("tags").IsSet() {
+					ok, err := checkBuildTags(strings.Split(app.Get("tags").String(), ","), path)
+					if err != nil {
+						return err
+					}
+					if !ok {
+						return nil
+					}
+				}
 				files = append(files, path)
 			}
 			return nil
@@ -139,8 +151,8 @@ func Scan(app args.App) error {
 
 	}
 
-	if app.Get("print").IsSet() {
-		fmt.Println(v.EnvByFile())
+	if app.Bool("print") {
+		fmt.Println("by file", v.EnvByFile())
 		return nil
 	}
 	fmt.Println(v.ToEnvFile())
@@ -156,3 +168,9 @@ func isPiped() bool {
 
 	return info.Mode()&os.ModeCharDevice == 0
 }
+
+func checkBuildTags(tags []string, path string) (bool, error) {
+	context := build.Default
+	context.BuildTags = tags
+	return context.MatchFile(filepath.Dir(path), filepath.Base(path))
+}
diff --git a/scan/scan_test.go b/scan/scan_test.go
index fc1d1f4..5037ad5 100644
--- a/scan/scan_test.go
+++ b/scan/scan_test.go
@@ -1,7 +1,7 @@
 package scan_test
 
 import (
-	"io/ioutil"
+	"io"
 	"os"
 	"strings"
 	"testing"
@@ -12,7 +12,7 @@ import (
 
 func TestScan(t *testing.T) {
 	is := is.New(t)
-	os.Args = []string{"./test", "-f", "./test_project/main.go"}
+	os.Args = []string{"./test", "-d", "./test_project", "-t", "test_tags,other_test"}
 	err := scan.Args.Parse()
 	is.NoErr(err)
 	// hijack stdout
@@ -22,8 +22,8 @@ func TestScan(t *testing.T) {
 	err = scan.Scan(scan.Args)
 	is.NoErr(err)
 	w.Close()
-	out, _ := ioutil.ReadAll(r)
-	os.Stdout = rescueStdout
+	out, _ := io.ReadAll(r)
 	// use hijacked output
-	is.True(strings.Compare(strings.ReplaceAll(string(out), "\n", ""), `ENV=""PORT="6969"`) == 0)
+	os.Stdout = rescueStdout
+	is.True(strings.Compare(strings.ReplaceAll(string(out), "\n", ""), `ENV=""PORT="6969"BUILD_TAG=""`) == 0)
 }
diff --git a/scan/test_project/other.go b/scan/test_project/other.go
new file mode 100644
index 0000000..390f90a
--- /dev/null
+++ b/scan/test_project/other.go
@@ -0,0 +1,9 @@
+//go:build test_tags && other_test
+
+package main
+
+import "github.com/taybart/env"
+
+func init() {
+	env.Add([]string{"BUILD_TAG"})
+}