diff --git a/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Cargo.java b/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Cargo.java
index 0c2e010591..0e8008e4e6 100644
--- a/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Cargo.java
+++ b/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Cargo.java
@@ -26,10 +26,14 @@
 import com.moandjiezana.toml.TomlWriter;
 import java.io.File;
 import java.io.IOException;
+import java.io.OutputStream;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;
+
+import org.cactoos.io.OutputStreamTo;
+import org.cactoos.io.OutputTo;
 import org.cactoos.map.MapEntry;
 import org.cactoos.map.MapOf;
 
@@ -40,7 +44,7 @@
  *  This class have save method and needs to have explanatory
  *  comment too via Commented class.
  */
-public class Cargo {
+public class Cargo extends Savable {
     /**
      * Package attributes.
      */
@@ -61,6 +65,10 @@ public class Cargo {
      * @param name Name of lib.
      */
     public Cargo(final String name) {
+        super(
+            name,
+            "rs"
+        );
         this.pack = new MapOf<>(
             new MapEntry<>("name", name),
             new MapEntry<>("version", "0.1.0"),
@@ -85,17 +93,15 @@ public void add(final String crate, final Object content) {
 
     /**
      * Save it to specified folder.
-     * @param target Directory where to save to.
      * @throws IOException If any issues with I/O
      */
-    public void save(final File target) throws IOException {
+    public String content() {
         final Map<String, Object> raw = new HashMap<>();
         raw.put("package", this.pack);
         raw.put("dependencies", this.dependencies);
         raw.put("lib", this.lib);
-        new TomlWriter().write(
-            raw,
-            target
+        return new TomlWriter().write(
+            raw
         );
     }
 }
diff --git a/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Commented.java b/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Commented.java
index 2a8b85d201..c1149ff41f 100644
--- a/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Commented.java
+++ b/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Commented.java
@@ -31,22 +31,31 @@
  */
 public class Commented extends Savable {
 
+    final Savable origin;
+    final String start;
+
     /**
      * Ctor.
-     * @param original Original object to save.
+     * @param origin Original object to save.
      * @param start Prefix of commentary.
      */
-    public Commented(final Savable original, final String start) {
+    public Commented(final Savable origin, final String start) {
         super(
-            original.name,
-            original.ext,
-            () -> String.format(
-                "%s %s%s%s",
-                start,
-                new Disclaimer(),
-                System.lineSeparator(),
-                original.content.value()
-            )
+            origin.name,
+            origin.ext
+        );
+        this.origin = origin;
+        this.start = start;
+    }
+
+    @Override
+    String content() {
+        return String.format(
+            "%s %s%s%s",
+            this.start,
+            new Disclaimer(),
+            System.lineSeparator(),
+            this.origin.content()
         );
     }
 }
diff --git a/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Module.java b/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Module.java
index d60e515142..2fedeca51c 100644
--- a/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Module.java
+++ b/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Module.java
@@ -30,6 +30,8 @@
  */
 public class Module extends Savable {
 
+    final String raw;
+
     /**
      * Ctor.
      * @param raw Source code of rust insert.
@@ -38,8 +40,14 @@ public class Module extends Savable {
     public Module(final String raw, final String name) {
         super(
             name,
-            "rs",
-            () -> raw
+            "rs"
         );
+        this.raw = raw;
+    }
+
+    @Override
+    String content() {
+        return this.raw;
     }
+
 }
diff --git a/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Native.java b/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Native.java
index c138edc0ce..7f4db358b5 100644
--- a/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Native.java
+++ b/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Native.java
@@ -31,6 +31,8 @@
  */
 public final class Native extends Savable {
 
+    final String pack;
+
     /**
      * Ctor.
      * @param name Name of the class.
@@ -39,25 +41,30 @@ public final class Native extends Savable {
     public Native(final String name, final String pack) {
         super(
             name,
-            "java",
-            () -> String.join(
-                System.lineSeparator(),
-                String.format(
-                    "package %s;",
-                    pack
-                ),
-                "import org.eolang.Universe;",
-                String.format(
-                    "public class %s {",
-                    name
-                ),
-                String.format(
-                    "    public static native byte[] %s",
-                    name
-                ),
-                "        (final Universe universe);",
-                "}"
-            )
+            "java"
+        );
+        this.pack = pack;
+    }
+
+    @Override
+    String content() {
+        return String.join(
+            System.lineSeparator(),
+            String.format(
+                "package %s;",
+                pack
+            ),
+            "import org.eolang.Universe;",
+            String.format(
+                "public class %s {",
+                name
+            ),
+            String.format(
+                "    public static native byte[] %s",
+                name
+            ),
+            "        (final Universe universe);",
+            "}"
         );
     }
 }
diff --git a/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Project.java b/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Project.java
index 76a2195658..6f409de911 100644
--- a/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Project.java
+++ b/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Project.java
@@ -108,7 +108,7 @@ public Path save() throws IOException {
         for (final Module module: this.modules) {
             new Commented(module, "//").save(this.footprint);
         }
-        this.cargo.save(this.dest.resolve("Cargo.toml").toFile());
+        this.cargo.save(new FtDefault(this.dest.resolve("Cargo.toml")));
         return this.dest;
     }
 }
diff --git a/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Savable.java b/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Savable.java
index 4b407e98a7..572a3f83d8 100644
--- a/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Savable.java
+++ b/eo-maven-plugin/src/main/java/org/eolang/maven/rust/Savable.java
@@ -32,7 +32,7 @@
  * @since 0.30
  * @checkstyle VisibilityModifierCheck (20 lines)
  */
-public class Savable {
+public abstract class Savable {
 
     /**
      * Name of file.
@@ -47,18 +47,16 @@ public class Savable {
     /**
      * Content inside file.
      */
-    protected final Scalar<String> content;
+    abstract String content();
 
     /**
      * Ctor.
      * @param name Name of the file.
      * @param ext Extension.
-     * @param content Content.
      */
-    public Savable(final String name, final String ext, final Scalar<String> content) {
+    public Savable(final String name, final String ext) {
         this.name = name;
         this.ext = ext;
-        this.content = content;
     }
 
     /**
@@ -67,6 +65,6 @@ public Savable(final String name, final String ext, final Scalar<String> content
      * @throws IOException If any issues with IO.
      */
     public void save(final Footprint footprint) throws IOException {
-        footprint.save(this.name, this.ext, this.content);
+        footprint.save(this.name, this.ext, this::content);
     }
 }
diff --git a/eo-maven-plugin/src/test/java/org/eolang/maven/rust/CommentedTest.java b/eo-maven-plugin/src/test/java/org/eolang/maven/rust/CommentedTest.java
index 026920d4ca..7be62616a8 100644
--- a/eo-maven-plugin/src/test/java/org/eolang/maven/rust/CommentedTest.java
+++ b/eo-maven-plugin/src/test/java/org/eolang/maven/rust/CommentedTest.java
@@ -40,12 +40,17 @@ final class CommentedTest {
 
     @Test
     void addsComment(@TempDir final Path temp) throws Exception {
+        final String content = "content";
         new Commented(
             new Savable(
                 "name",
-                "ext",
-                () -> "content"
-            ),
+                "ext"
+            ) {
+                @Override
+                String content() {
+                    return content;
+                }
+            },
             "//"
         ).save(new FtDefault(temp));
         MatcherAssert.assertThat(
@@ -55,7 +60,7 @@ void addsComment(@TempDir final Path temp) throws Exception {
             Matchers.stringContainsInOrder(
                 "// This file was auto-generated by eo-maven-plugin",
                 System.lineSeparator(),
-                "content"
+                content
             )
         );
     }