diff --git a/.github/workflows/my-app/.gitignore b/.github/workflows/my-app/.gitignore
new file mode 100644
index 0000000..8d9590a
Binary files /dev/null and b/.github/workflows/my-app/.gitignore differ
diff --git a/.github/workflows/my-app/src/main/java/com/mycompany/app/App.java b/.github/workflows/my-app/src/main/java/com/mycompany/app/App.java
new file mode 100644
index 0000000..1dab526
--- /dev/null
+++ b/.github/workflows/my-app/src/main/java/com/mycompany/app/App.java
@@ -0,0 +1,10 @@
+package com.mycompany.app;
+
+public class App {
+    public static void main(String[] args) {
+        double val = Double.parseDouble("2.0");
+        Sqrt sqrt = new Sqrt(val);
+        double result = sqrt.calc();
+        System.out.println("Sqrt of " + val + " = " + result);
+    }
+}
diff --git a/.github/workflows/my-app/src/main/java/com/mycompany/app/Sqrt.java b/.github/workflows/my-app/src/main/java/com/mycompany/app/Sqrt.java
new file mode 100644
index 0000000..0ba567e
--- /dev/null
+++ b/.github/workflows/my-app/src/main/java/com/mycompany/app/Sqrt.java
@@ -0,0 +1,33 @@
+package com.mycompany.app;
+
+public class Sqrt {
+    double delta = 0.00000001;
+    double arg;
+
+    public Sqrt(double arg) {
+        this.arg = arg;
+    }
+
+    public double average(double x, double y) {
+        return (x + y) / 2.0;
+    }
+
+    public boolean good(double guess, double x) {
+        return Math.abs(guess * guess - x) < delta;
+    }
+
+    public double improve(double guess, double x) {
+        return average(guess, x / guess);
+    }
+
+    public double iter(double guess, double x) {
+        if (good(guess, x))
+            return guess;
+        else
+            return iter(improve(guess, x), x);
+    }
+
+    public double calc() {
+        return iter(1.0, arg);
+    }
+}
diff --git a/.github/workflows/my-app/src/test/java/com/mycompany/app/AppTest.java b/.github/workflows/my-app/src/test/java/com/mycompany/app/AppTest.java
new file mode 100644
index 0000000..c8b092b
--- /dev/null
+++ b/.github/workflows/my-app/src/test/java/com/mycompany/app/AppTest.java
@@ -0,0 +1,116 @@
+package com.mycompany.app;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.BeforeEach;
+import static org.junit.jupiter.api.Assertions.*;
+
+public class AppTest {
+
+    private static final double DELTA = 1e-6;
+
+    // --- Тесты метода calc() ---
+
+    @Test
+    public void testSqrtOf4() {
+        Sqrt sqrt = new Sqrt(4.0);
+        assertEquals(2.0, sqrt.calc(), DELTA);
+    }
+
+    @Test
+    public void testSqrtOf9() {
+        Sqrt sqrt = new Sqrt(9.0);
+        assertEquals(3.0, sqrt.calc(), DELTA);
+    }
+
+    @Test
+    public void testSqrtOf2() {
+        Sqrt sqrt = new Sqrt(2.0);
+        assertEquals(Math.sqrt(2.0), sqrt.calc(), DELTA);
+    }
+
+    @Test
+    public void testSqrtOf1() {
+        Sqrt sqrt = new Sqrt(1.0);
+        assertEquals(1.0, sqrt.calc(), DELTA);
+    }
+
+    @Test
+    public void testSqrtOf0() {
+        Sqrt sqrt = new Sqrt(0.0);
+        assertEquals(0.0, sqrt.calc(), DELTA);
+    }
+
+    @Test
+    public void testSqrtOf100() {
+        Sqrt sqrt = new Sqrt(100.0);
+        assertEquals(10.0, sqrt.calc(), DELTA);
+    }
+
+    @Test
+    public void testSqrtOf0Point25() {
+        Sqrt sqrt = new Sqrt(0.25);
+        assertEquals(0.5, sqrt.calc(), DELTA);
+    }
+
+    // --- Тесты метода average() ---
+
+    @Test
+    public void testAverageOfTwoNumbers() {
+        Sqrt sqrt = new Sqrt(1.0);
+        assertEquals(3.0, sqrt.average(2.0, 4.0), DELTA);
+    }
+
+    @Test
+    public void testAverageOfSameNumbers() {
+        Sqrt sqrt = new Sqrt(1.0);
+        assertEquals(5.0, sqrt.average(5.0, 5.0), DELTA);
+    }
+
+    @Test
+    public void testAverageOfZeroAndNumber() {
+        Sqrt sqrt = new Sqrt(1.0);
+        assertEquals(2.5, sqrt.average(0.0, 5.0), DELTA);
+    }
+
+    // --- Тесты метода good() ---
+
+    @Test
+    public void testGoodReturnsTrueForExactSqrt() {
+        Sqrt sqrt = new Sqrt(4.0);
+        assertTrue(sqrt.good(2.0, 4.0));
+    }
+
+    @Test
+    public void testGoodReturnsFalseForBadGuess() {
+        Sqrt sqrt = new Sqrt(4.0);
+        assertFalse(sqrt.good(1.0, 4.0));
+    }
+
+    // --- Тесты метода improve() ---
+
+    @Test
+    public void testImproveConvergesCloser() {
+        Sqrt sqrt = new Sqrt(4.0);
+        double improved = sqrt.improve(1.0, 4.0);
+        double distBefore = Math.abs(1.0 * 1.0 - 4.0);
+        double distAfter = Math.abs(improved * improved - 4.0);
+        assertTrue(distAfter < distBefore);
+    }
+
+    // --- Тесты метода iter() ---
+
+    @Test
+    public void testIterConvergesFor9() {
+        Sqrt sqrt = new Sqrt(9.0);
+        assertEquals(3.0, sqrt.iter(1.0, 9.0), DELTA);
+    }
+
+    // --- Точность результата ---
+
+    @Test
+    public void testCalcAccuracy() {
+        Sqrt sqrt = new Sqrt(2.0);
+        double result = sqrt.calc();
+        assertTrue(Math.abs(result * result - 2.0) < 1e-7);
+    }
+}
diff --git a/pom.xml b/pom.xml
new file mode 100644
index 0000000..fa10819
--- /dev/null
+++ b/pom.xml
@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>com.mycompany.app</groupId>
+  <artifactId>my-app</artifactId>
+  <version>1.0-SNAPSHOT</version>
+  <packaging>jar</packaging>
+
+  <properties>
+    <maven.compiler.source>11</maven.compiler.source>
+    <maven.compiler.target>11</maven.compiler.target>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter</artifactId>
+      <version>5.10.0</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <version>3.1.2</version>
+      </plugin>
+    </plugins>
+  </build>
+</project>