diff --git a/cli/yaml2json/build.gradle b/cli/yaml2json/build.gradle
new file mode 100644
index 0000000..d67dbf1
--- /dev/null
+++ b/cli/yaml2json/build.gradle
@@ -0,0 +1,96 @@
+import com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar
+import org.graalvm.buildtools.gradle.dsl.NativeImageOptions
+
+plugins {
+    id 'info.ankin.projects.app-conventions'
+}
+
+version = '0.0.1'
+
+dependencies {
+    implementation 'com.fasterxml.jackson.dataformat:jackson-dataformat-yaml:2.13.2'
+}
+
+// for shadowJar
+application.mainClass.set 'info.ankin.projects.cli.yaml2json.Yaml2Json'
+
+shadowJar {
+    // output first jar as "shadow"
+    // so as not to confuse with yaml2json and json2Yaml
+    archiveBaseName.set 'shadow'
+}
+
+void customShadowJar(ShadowJar s, String name, String className) {
+    s.group 'shadow'
+    s.description name + 'Jar shadow jar'
+    s.archiveBaseName.set name
+    s.manifest {
+        attributes('Main-Class': 'info.ankin.projects.cli.yaml2json.' + className)
+    }
+    s.from zipTree(tasks.shadowJar.getArchiveFile())
+}
+
+def yaml2JsonJar = tasks.register('yaml2JsonJar', ShadowJar) {
+    customShadowJar(it, 'yaml2Json', 'Yaml2Json')
+}
+
+def json2YamlJar = tasks.register('json2YamlJar', ShadowJar) {
+    customShadowJar(it, 'json2Yaml', 'Json2Yaml')
+}
+
+tasks {
+    shadowJar {
+        finalizedBy yaml2JsonJar, json2YamlJar
+    }
+}
+
+task example {
+    doLast {
+        println
+    }
+}
+
+// for graalvmNative
+tasks.jar.enabled(true)
+
+// https://graalvm.github.io/native-build-tools/0.9.11/gradle-plugin.html#_configuration_options
+graalvmNative {
+    binaries  {
+        json2yaml { NativeImageOptions o ->
+            o.imageName.set 'json2yaml'
+            o.mainClass.set json2YamlJar.get().getManifest().getAttributes().get('Main-Class')
+
+            o.debug.set false
+            o.verbose.set true
+            o.fallback.set false
+            o.buildArgs.add('-Ob') // faster development builds
+            o.useFatJar.set false
+            o.classpath sourceSets.main.output.files, project.tasks.shadowJar
+        }
+
+        yaml2json { NativeImageOptions o ->
+            o.imageName.set 'yaml2json'
+            o.mainClass.set yaml2JsonJar.get().getManifest().getAttributes().get('Main-Class')
+            o.debug.set false
+            o.verbose.set true
+            o.fallback.set false
+            o.buildArgs.add('-Ob') // faster development builds
+            o.useFatJar.set false
+            o.classpath sourceSets.main.output.files, project.tasks.shadowJar
+        }
+    }
+}
+
+tasks {
+    nativeCompile {
+        dependsOn nativeYaml2jsonCompile, nativeJson2yamlCompile
+        doLast {
+            copy {
+                from tasks.nativeJson2yamlCompile.outputs.files.files
+                from tasks.nativeYaml2jsonCompile.outputs.files.files
+
+                into tasks.nativeCompile.outputs.files.singleFile
+            }
+        }
+    }
+}
diff --git a/cli/yaml2json/src/main/java/info/ankin/projects/cli/yaml2json/Json2Yaml.java b/cli/yaml2json/src/main/java/info/ankin/projects/cli/yaml2json/Json2Yaml.java
new file mode 100644
index 0000000..35a1e88
--- /dev/null
+++ b/cli/yaml2json/src/main/java/info/ankin/projects/cli/yaml2json/Json2Yaml.java
@@ -0,0 +1,20 @@
+package info.ankin.projects.cli.yaml2json;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.json.JsonMapper;
+import com.fasterxml.jackson.dataformat.yaml.YAMLMapper;
+import lombok.SneakyThrows;
+
+public class Json2Yaml {
+    @SneakyThrows
+    public static void main(String[] args) {
+        JsonMapper jsonMapper = new JsonMapper();
+        YAMLMapper yamlMapper = new YAMLMapper();
+        yamlMapper.disable(JsonGenerator.Feature.AUTO_CLOSE_TARGET);
+
+        JsonNode jsonNode = jsonMapper.reader().readTree(System.in);
+        yamlMapper.writeValue(System.out, jsonNode);
+        System.out.println();
+    }
+}
diff --git a/cli/yaml2json/src/main/java/info/ankin/projects/cli/yaml2json/Yaml2Json.java b/cli/yaml2json/src/main/java/info/ankin/projects/cli/yaml2json/Yaml2Json.java
new file mode 100644
index 0000000..fa46c6c
--- /dev/null
+++ b/cli/yaml2json/src/main/java/info/ankin/projects/cli/yaml2json/Yaml2Json.java
@@ -0,0 +1,20 @@
+package info.ankin.projects.cli.yaml2json;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.json.JsonMapper;
+import com.fasterxml.jackson.dataformat.yaml.YAMLMapper;
+import lombok.SneakyThrows;
+
+public class Yaml2Json {
+    @SneakyThrows
+    public static void main(String[] args) {
+        JsonMapper jsonMapper = new JsonMapper();
+        jsonMapper.disable(JsonGenerator.Feature.AUTO_CLOSE_TARGET);
+        YAMLMapper yamlMapper = new YAMLMapper();
+
+        JsonNode jsonNode = yamlMapper.reader().readTree(System.in);
+        jsonMapper.writeValue(System.out, jsonNode);
+        System.out.println();
+    }
+}
diff --git a/settings.gradle b/settings.gradle
index 672b332..937ae6a 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -1,4 +1,5 @@
 rootProject.name = 'java-projects'
 include 'cli:killport'
+include 'cli:yaml2json'
 include 'system:infer-platform'
 include 'system:terminal:supports-hyperlinks'