diff --git a/pkg/yamlgen/yamlgen_test.go b/pkg/yamlgen/yamlgen_test.go
new file mode 100644
index 0000000..77f7d81
--- /dev/null
+++ b/pkg/yamlgen/yamlgen_test.go
@@ -0,0 +1,60 @@
+// Copyright (c) Bartłomiej Płotka @bwplotka
+// Licensed under the Apache License 2.0.
+
+package yamlgen
+
+import (
+	"testing"
+
+	"github.com/efficientgo/tools/core/pkg/testutil"
+	"golang.org/x/net/context"
+)
+
+func TestYAMLGen_GenGoCode(t *testing.T) {
+	t.Run("normal struct", func(t *testing.T) {
+		source := []byte("package main\n\ntype TestConfig struct {\n\tUrl   string `yaml:\"url\"`\n\tID    int    `yaml:\"id\"`\n\tToken string `yaml:\"token\"`\n}\n")
+		generatedCode, err := GenGoCode(source)
+		testutil.Ok(t, err)
+
+		expected := "package main\n\nimport (\n\t\"fmt\"\n\tyamlgen \"github.com/bwplotka/mdox/pkg/yamlgen\"\n\t\"os\"\n)\n\ntype TestConfig struct {\n\tUrl   string `yaml:\"url\"`\n\tID    int    `yaml:\"id\"`\n\tToken string `yaml:\"token\"`\n}\n\nfunc main() {\n\tconfigs := map[string]interface{}{}\n\tconfigs[\"TestConfig\"] = TestConfig{}\n\tfor k, config := range configs {\n\t\tfmt.Println(\"---\")\n\t\tfmt.Println(k)\n\t\tyamlgen.Generate(config, os.Stderr)\n\t}\n}\n"
+		testutil.Equals(t, expected, generatedCode)
+	})
+
+	t.Run("struct with unexported field", func(t *testing.T) {
+		source := []byte("package main\n\nimport \"regexp\"\n\ntype ValidatorConfig struct {\n\tType  string `yaml:\"type\"`\n\tRegex string `yaml:\"regex\"`\n\tToken string `yaml:\"token\"`\n\n\tr *regexp.Regexp\n}\n")
+		generatedCode, err := GenGoCode(source)
+		testutil.Ok(t, err)
+
+		expected := "package main\n\nimport (\n\t\"fmt\"\n\tyamlgen \"github.com/bwplotka/mdox/pkg/yamlgen\"\n\t\"os\"\n)\n\ntype ValidatorConfig struct {\n\tType  string `yaml:\"type\"`\n\tRegex string `yaml:\"regex\"`\n\tToken string `yaml:\"token\"`\n}\n\nfunc main() {\n\tconfigs := map[string]interface{}{}\n\tconfigs[\"ValidatorConfig\"] = ValidatorConfig{}\n\tfor k, config := range configs {\n\t\tfmt.Println(\"---\")\n\t\tfmt.Println(k)\n\t\tyamlgen.Generate(config, os.Stderr)\n\t}\n}\n"
+		testutil.Equals(t, expected, generatedCode)
+	})
+
+	t.Run("struct with array fields", func(t *testing.T) {
+		source := []byte("package main\n\nimport \"regexp\"\n\ntype Config struct {\n\tVersion int `yaml:\"version\"`\n\n\tValidator []ValidatorConfig `yaml:\"validators\"`\n\tIgnore    []IgnoreConfig    `yaml:\"ignore\"`\n}\n\ntype ValidatorConfig struct {\n\tType  string `yaml:\"type\"`\n\tRegex string `yaml:\"regex\"`\n\tToken string `yaml:\"token\"`\n\n\tr *regexp.Regexp\n}\n\ntype IgnoreConfig struct {\n\tUrl   string `yaml:\"url\"`\n\tID    int    `yaml:\"id\"`\n\tToken string `yaml:\"token\"`\n}\n")
+		generatedCode, err := GenGoCode(source)
+		testutil.Ok(t, err)
+
+		expected := "package main\n\nimport (\n\t\"fmt\"\n\tyamlgen \"github.com/bwplotka/mdox/pkg/yamlgen\"\n\t\"os\"\n)\n\ntype Config struct {\n\tVersion   int               `yaml:\"version\"`\n\tValidator []ValidatorConfig `yaml:\"validators\"`\n\tIgnore    []IgnoreConfig    `yaml:\"ignore\"`\n}\ntype ValidatorConfig struct {\n\tType  string `yaml:\"type\"`\n\tRegex string `yaml:\"regex\"`\n\tToken string `yaml:\"token\"`\n}\ntype IgnoreConfig struct {\n\tUrl   string `yaml:\"url\"`\n\tID    int    `yaml:\"id\"`\n\tToken string `yaml:\"token\"`\n}\n\nfunc main() {\n\tconfigs := map[string]interface{}{}\n\tconfigs[\"Config\"] = Config{\n\t\tIgnore:    []IgnoreConfig{IgnoreConfig{}},\n\t\tValidator: []ValidatorConfig{ValidatorConfig{}},\n\t}\n\tconfigs[\"ValidatorConfig\"] = ValidatorConfig{}\n\tconfigs[\"IgnoreConfig\"] = IgnoreConfig{}\n\tfor k, config := range configs {\n\t\tfmt.Println(\"---\")\n\t\tfmt.Println(k)\n\t\tyamlgen.Generate(config, os.Stderr)\n\t}\n}\n"
+		testutil.Equals(t, expected, generatedCode)
+	})
+}
+
+func TestYAMLGen_ExecGoCode(t *testing.T) {
+	t.Run("normal struct", func(t *testing.T) {
+		generatedCode := "package main\n\nimport (\n\t\"fmt\"\n\tyamlgen \"github.com/bwplotka/mdox/pkg/yamlgen\"\n\t\"os\"\n)\n\ntype TestConfig struct {\n\tUrl   string `yaml:\"url\"`\n\tID    int    `yaml:\"id\"`\n\tToken string `yaml:\"token\"`\n}\n\nfunc main() {\n\tconfigs := map[string]interface{}{}\n\tconfigs[\"TestConfig\"] = TestConfig{}\n\tfor k, config := range configs {\n\t\tfmt.Println(\"---\")\n\t\tfmt.Println(k)\n\t\tyamlgen.Generate(config, os.Stderr)\n\t}\n}\n"
+		output, err := ExecGoCode(context.TODO(), generatedCode)
+		testutil.Ok(t, err)
+
+		expected := "---\nTestConfig\nurl: \"\"\nid: 0\ntoken: \"\"\n"
+		testutil.Equals(t, expected, string(output))
+	})
+
+	t.Run("struct with array fields", func(t *testing.T) {
+		generatedCode := "package main\n\nimport (\n\t\"fmt\"\n\tyamlgen \"github.com/bwplotka/mdox/pkg/yamlgen\"\n\t\"os\"\n)\n\ntype Config struct {\n\tVersion   int               `yaml:\"version\"`\n\tValidator []ValidatorConfig `yaml:\"validators\"`\n\tIgnore    []IgnoreConfig    `yaml:\"ignore\"`\n}\ntype ValidatorConfig struct {\n\tType  string `yaml:\"type\"`\n\tRegex string `yaml:\"regex\"`\n\tToken string `yaml:\"token\"`\n}\ntype IgnoreConfig struct {\n\tUrl   string `yaml:\"url\"`\n\tID    int    `yaml:\"id\"`\n\tToken string `yaml:\"token\"`\n}\n\nfunc main() {\n\tconfigs := map[string]interface{}{}\n\tconfigs[\"Config\"] = Config{\n\t\tIgnore:    []IgnoreConfig{IgnoreConfig{}},\n\t\tValidator: []ValidatorConfig{ValidatorConfig{}},\n\t}\n\tconfigs[\"ValidatorConfig\"] = ValidatorConfig{}\n\tconfigs[\"IgnoreConfig\"] = IgnoreConfig{}\n\tfor k, config := range configs {\n\t\tfmt.Println(\"---\")\n\t\tfmt.Println(k)\n\t\tyamlgen.Generate(config, os.Stderr)\n\t}\n}\n"
+		output, err := ExecGoCode(context.TODO(), generatedCode)
+		testutil.Ok(t, err)
+
+		expected := "---\nConfig\nversion: 0\nvalidators:\n    - type: \"\"\n      regex: \"\"\n      token: \"\"\nignore:\n    - url: \"\"\n      id: 0\n      token: \"\"\n---\nValidatorConfig\ntype: \"\"\nregex: \"\"\ntoken: \"\"\n---\nIgnoreConfig\nurl: \"\"\nid: 0\ntoken: \"\"\n"
+		testutil.Equals(t, expected, string(output))
+	})
+}