diff --git a/demo/02/.gitignore b/demo/02/.gitignore
new file mode 100644
index 0000000..2a91258
--- /dev/null
+++ b/demo/02/.gitignore
@@ -0,0 +1,201 @@
+
+# Created by https://www.gitignore.io/api/java,maven,eclipse,intellij+all,visualstudiocode
+# Edit at https://www.gitignore.io/?templates=java,maven,eclipse,intellij+all,visualstudiocode
+
+.metadata
+bin/
+tmp/
+*.tmp
+*.bak
+*.swp
+*~.nib
+local.properties
+.settings/
+.loadpath
+.recommenders
+
+# External tool builders
+.externalToolBuilders/
+
+# Locally stored "Eclipse launch configurations"
+*.launch
+
+# PyDev specific (Python IDE for Eclipse)
+*.pydevproject
+
+# CDT-specific (C/C++ Development Tooling)
+.cproject
+
+# CDT- autotools
+.autotools
+
+# Java annotation processor (APT)
+.factorypath
+
+# PDT-specific (PHP Development Tools)
+.buildpath
+
+# sbteclipse plugin
+.target
+
+# Tern plugin
+.tern-project
+
+# TeXlipse plugin
+.texlipse
+
+# STS (Spring Tool Suite)
+.springBeans
+
+# Code Recommenders
+.recommenders/
+
+# Annotation Processing
+.apt_generated/
+
+# Scala IDE specific (Scala & Java development for Eclipse)
+.cache-main
+.scala_dependencies
+.worksheet
+
+# Eclipse Core
+.project
+
+# JDT-specific (Eclipse Java Development Tools)
+.classpath
+
+# Annotation Processing
+.apt_generated
+
+.sts4-cache/
+
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and WebStorm
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/**/usage.statistics.xml
+.idea/**/dictionaries
+.idea/**/shelf
+
+# Generated files
+.idea/**/contentModel.xml
+
+# Sensitive or high-churn files
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+.idea/**/dbnavigator.xml
+
+# Gradle
+.idea/**/gradle.xml
+.idea/**/libraries
+
+# Gradle and Maven with auto-import
+# When using Gradle or Maven with auto-import, you should exclude module files,
+# since they will be recreated, and may cause churn.  Uncomment if using
+# auto-import.
+# .idea/modules.xml
+# .idea/*.iml
+# .idea/modules
+# *.iml
+# *.ipr
+
+# CMake
+cmake-build-*/
+
+# Mongo Explorer plugin
+.idea/**/mongoSettings.xml
+
+# File-based project format
+*.iws
+
+# IntelliJ
+out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Cursive Clojure plugin
+.idea/replstate.xml
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties
+
+# Editor-based Rest Client
+.idea/httpRequests
+
+# Android studio 3.1+ serialized cache file
+.idea/caches/build_file_checksums.ser
+
+# Ignores the whole .idea folder and all .iml files
+# See https://github.com/joeblau/gitignore.io/issues/186 and https://github.com/joeblau/gitignore.io/issues/360
+
+.idea/
+
+# Reason: https://github.com/joeblau/gitignore.io/issues/186#issuecomment-249601023
+
+*.iml
+modules.xml
+.idea/misc.xml
+*.ipr
+
+# Sonarlint plugin
+.idea/sonarlint
+
+# Compiled class file
+*.class
+
+# Log file
+*.log
+
+# BlueJ files
+*.ctxt
+
+# Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+# Package Files #
+*.jar
+*.war
+*.nar
+*.ear
+*.zip
+*.tar.gz
+*.rar
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+hs_err_pid*
+
+target/
+pom.xml.tag
+pom.xml.releaseBackup
+pom.xml.versionsBackup
+pom.xml.next
+release.properties
+dependency-reduced-pom.xml
+buildNumber.properties
+.mvn/timing.properties
+.mvn/wrapper/maven-wrapper.jar
+.flattened-pom.xml
+
+.vscode/*
+!.vscode/settings.json
+!.vscode/tasks.json
+!.vscode/launch.json
+!.vscode/extensions.json
+
+# Ignore all local history of files
+.history
+
+# End of https://www.gitignore.io/api/java,maven,eclipse,intellij+all,visualstudiocode
\ No newline at end of file
diff --git a/demo/02/README.md b/demo/02/README.md
new file mode 100644
index 0000000..cbb5bf6
--- /dev/null
+++ b/demo/02/README.md
@@ -0,0 +1 @@
+# Demonstracja TDD
diff --git a/demo/02/pom.xml b/demo/02/pom.xml
new file mode 100644
index 0000000..9ed57d9
--- /dev/null
+++ b/demo/02/pom.xml
@@ -0,0 +1,100 @@
+<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+ 
+    <groupId>pl.amu.edu</groupId>
+    <artifactId>demo-02-testing</artifactId>
+    <version>1.0-SNAPSHOT</version>
+    <packaging>jar</packaging>
+ 
+    <name>cw1</name>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <java.version>11</java.version>
+        <maven.compiler.source>${java.version}</maven.compiler.source>
+        <maven.compiler.target>${java.version}</maven.compiler.target>
+        <maven.compiler.release>${java.version}</maven.compiler.release>
+
+        <lombok.version>1.18.24</lombok.version>
+        <junit.version>5.9.0</junit.version>
+        <assertj.version>3.23.1</assertj.version>
+        <mockito.version>4.8.0</mockito.version>
+        
+        <!-- Plugin versions -->
+        <maven.shade>3.2.2</maven.shade>
+        <maven.compiler>3.8.1</maven.compiler>
+    </properties>
+
+    <dependencies>
+        <!-- Dependencies -->
+
+        <!-- Code dependencies -->
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>${lombok.version}</version>
+            <scope>provided</scope>
+        </dependency>
+
+    
+        <!-- Testing dependencies-->
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-api</artifactId>
+            <version>${junit.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+            <version>${junit.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-params</artifactId>
+            <version>${junit.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-junit-jupiter</artifactId>
+            <version>${mockito.version}</version>
+            <scope>test</scope>
+        </dependency>
+        
+</dependencies>
+    
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-shade-plugin</artifactId>
+                <version>${maven.shade}</version>
+                <executions>
+                <execution>
+                    <phase>package</phase>
+                    <goals>
+                    <goal>shade</goal>
+                    </goals>
+                    <configuration>
+                    <transformers>
+                        <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
+                        <mainClass>org.example.App</mainClass>
+                        </transformer>
+                    </transformers>
+                    </configuration>
+                </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+</project>
diff --git a/demo/02/src/main/java/pl/amu/edu/demo/data/Address.java b/demo/02/src/main/java/pl/amu/edu/demo/data/Address.java
new file mode 100644
index 0000000..6e13044
--- /dev/null
+++ b/demo/02/src/main/java/pl/amu/edu/demo/data/Address.java
@@ -0,0 +1,13 @@
+package pl.amu.edu.demo.data;
+
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.experimental.FieldDefaults;
+
+@AllArgsConstructor
+@FieldDefaults(level = AccessLevel.PUBLIC, makeFinal = true)
+public class Address {
+    String addressLine1;
+    String addressLine2;
+    String zipCode;
+}
diff --git a/demo/02/src/main/java/pl/amu/edu/demo/data/Housing.java b/demo/02/src/main/java/pl/amu/edu/demo/data/Housing.java
new file mode 100644
index 0000000..79d0f71
--- /dev/null
+++ b/demo/02/src/main/java/pl/amu/edu/demo/data/Housing.java
@@ -0,0 +1,12 @@
+package pl.amu.edu.demo.data;
+
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.experimental.FieldDefaults;
+
+@AllArgsConstructor
+@FieldDefaults(level = AccessLevel.PUBLIC, makeFinal = true)
+public class Housing {
+    Address address;
+    boolean isApartment;
+}
diff --git a/demo/02/src/main/java/pl/amu/edu/demo/data/Person.java b/demo/02/src/main/java/pl/amu/edu/demo/data/Person.java
new file mode 100644
index 0000000..e1b4463
--- /dev/null
+++ b/demo/02/src/main/java/pl/amu/edu/demo/data/Person.java
@@ -0,0 +1,18 @@
+package pl.amu.edu.demo.data;
+
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.experimental.FieldDefaults;
+
+import java.time.LocalDate;
+
+@AllArgsConstructor
+@FieldDefaults(level = AccessLevel.PUBLIC, makeFinal = true)
+public class Person {
+    String displayName;
+    String firstName;
+    String lastName;
+    LocalDate birthDate;
+    Housing housing;
+    boolean isMarried;
+}
diff --git a/demo/02/src/main/java/pl/amu/edu/demo/providers/AverageQuoteProvider.java b/demo/02/src/main/java/pl/amu/edu/demo/providers/AverageQuoteProvider.java
new file mode 100644
index 0000000..ab28966
--- /dev/null
+++ b/demo/02/src/main/java/pl/amu/edu/demo/providers/AverageQuoteProvider.java
@@ -0,0 +1,7 @@
+package pl.amu.edu.demo.providers;
+
+public interface AverageQuoteProvider {
+
+    double getAverageQuotePerSquareMeter(String zipCode);
+
+}
diff --git a/demo/02/src/test/java/TestStash.java b/demo/02/src/test/java/TestStash.java
new file mode 100644
index 0000000..4c405ee
--- /dev/null
+++ b/demo/02/src/test/java/TestStash.java
@@ -0,0 +1,27 @@
+import org.junit.jupiter.api.Test;
+import pl.amu.edu.demo.data.Person;
+
+import java.time.LocalDate;
+
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+public class TestStash {
+
+    @Test
+    public void shouldWhatever() {
+        // given
+        var person = new Person("lama", "frama", "lama", LocalDate.now(), null, false);
+
+        // when
+        var date = person.birthDate;
+
+        // then
+//        assertThat(date).isNotNull();
+        assertThrows(IllegalArgumentException.class, this::throwMeOut);
+    }
+
+    private void throwMeOut() {
+        throw new IllegalArgumentException();
+    }
+
+}
diff --git a/demo/02/src/test/java/pl/amu/edu/demo/logic/TestWeWillStealYourFlatProduct.java b/demo/02/src/test/java/pl/amu/edu/demo/logic/TestWeWillStealYourFlatProduct.java
new file mode 100644
index 0000000..9d444f4
--- /dev/null
+++ b/demo/02/src/test/java/pl/amu/edu/demo/logic/TestWeWillStealYourFlatProduct.java
@@ -0,0 +1,19 @@
+package pl.amu.edu.demo.logic;
+
+import org.junit.jupiter.api.Test;
+
+public class TestWeWillStealYourFlatProduct {
+
+    @Test
+    public void shouldBeValid() {
+        // given
+        /* preconditions */
+
+        // when
+        /* when we perform an action */
+
+        // then
+        /* assert that everything works as expected */
+    }
+
+}