diff --git a/backend/individual-assignment/challenge/.gitignore b/backend/individual-assignment/challenge/.gitignore
new file mode 100644
index 00000000..b63da455
--- /dev/null
+++ b/backend/individual-assignment/challenge/.gitignore
@@ -0,0 +1,42 @@
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### IntelliJ IDEA ###
+.idea/modules.xml
+.idea/jarRepositories.xml
+.idea/compiler.xml
+.idea/libraries/
+*.iws
+*.iml
+*.ipr
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### Eclipse ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
+
+### Mac OS ###
+.DS_Store
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/build.gradle.kts b/backend/individual-assignment/challenge/build.gradle.kts
new file mode 100644
index 00000000..47087801
--- /dev/null
+++ b/backend/individual-assignment/challenge/build.gradle.kts
@@ -0,0 +1,18 @@
+plugins {
+    kotlin("jvm") version "2.0.0"
+}
+
+group = "org.example"
+version = "1.0-SNAPSHOT"
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    testImplementation(kotlin("test"))
+}
+
+tasks.test {
+    useJUnitPlatform()
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/explain.md b/backend/individual-assignment/challenge/explain.md
new file mode 100644
index 00000000..1f64a1e3
--- /dev/null
+++ b/backend/individual-assignment/challenge/explain.md
@@ -0,0 +1,39 @@
+# Hello, My Dear (and Maybe Future Leader and Co-worker)
+
+Even though the entire process so far has been in Portuguese, I am providing this document in English to encourage a broader mindset. I hope you enjoy the code! :3
+
+## Problem
+
+You are reviewing the design decisions of software that processes online orders. For these orders, payments are handled based on specific situations:
+
+- If the payment is for a physical item, a shipping label must be generated and placed in the shipping box.
+- If the payment is for a service subscription, the subscription must be activated, and the user notified via email.
+- If the payment is for an ordinary book, a shipping label must be generated with a notification that it is a tax-exempt item as provided in the Constitution Art. 150, VI, d.
+- If the payment is for any digital media (music, video), in addition to sending a purchase confirmation email to the buyer, a $10 discount voucher must be granted to the buyer associated with the payment.
+
+## Solution
+
+A new method `processProduct` was added to the `Order` class, which calls auxiliary functions that are executed based on the provided `Enum` type, similar to a map. You can check these functions in `kotlin/extension/ProductTypeProcess.kt`.
+
+After the payment is set, we must proceed with the shipping or provisioning process. Although it was not implemented, it is noted that a database transactional approach would be ideal to cancel the payment in case of an internal error during the shipping process.
+
+Regarding the process functions, an expanding approach was attempted. They route to classes that process the order information and utilize their specific data:
+
+- **physicalProcess**: Address validation was set to demonstrate exception test cases. The shipping method is the same and can extend the possible taxes by using a list of an enum, placing them in order to make them exempt from the given tax.
+- **bookProcess**: This method uses the same function as `physicalProcess`, but passes `Taxes.SHIP_ART_150` to make it exempt.
+- **digitalProcess**: Calls `DigitalPurchaseImpl`, which has the `sendMailWithVoucher` function, receiving a `SendEmailImpl`. `SendEmailImpl` is a black box that creates the email body, with or without a voucher. `DigitalProcess` has a companion object with a default voucher, which can be changed according to the situation, making it easier to provide random vouchers or larger vouchers based on the number of purchases.
+- **membershipProcess**: Also calls `SendEmailImpl`, and uses `MembershipImpl`, which validates the customer, checks if they are already a member, and proceeds accordingly before sending the email. If the business decides that the member should now receive a voucher, it can be easily changed.
+
+SOLID principles were applied, ensuring that functions have single responsibilities, adhere to Open/Closed principles, etc.
+
+The project structure follows Kotlin patterns.
+
+The test class has a 'Fixture' folder, which I prefer to create for objects, as they can become more complex, only copying certain values and changing them.
+
+**Note:**
+The `Order` class would be better as a Data Class, with an implementation that receives an `OrderDto` and deals with its data, avoiding a larger fixture class for tests as we could use the `.copy()` method.
+
+Whether we proceed with this process or not, let’s connect and maybe share knowledge! ^~^  
+[LinkedIn](https://www.linkedin.com/in/gabrielteixeirasoares/)
+
+See ya!
diff --git a/backend/individual-assignment/challenge/gradle.properties b/backend/individual-assignment/challenge/gradle.properties
new file mode 100644
index 00000000..7fc6f1ff
--- /dev/null
+++ b/backend/individual-assignment/challenge/gradle.properties
@@ -0,0 +1 @@
+kotlin.code.style=official
diff --git a/backend/individual-assignment/challenge/gradle/wrapper/gradle-wrapper.jar b/backend/individual-assignment/challenge/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 00000000..249e5832
Binary files /dev/null and b/backend/individual-assignment/challenge/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/backend/individual-assignment/challenge/gradle/wrapper/gradle-wrapper.properties b/backend/individual-assignment/challenge/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 00000000..b55f55f1
--- /dev/null
+++ b/backend/individual-assignment/challenge/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,6 @@
+#Tue Aug 13 20:31:16 BRT 2024
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.8-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/backend/individual-assignment/challenge/gradlew b/backend/individual-assignment/challenge/gradlew
new file mode 100644
index 00000000..1b6c7873
--- /dev/null
+++ b/backend/individual-assignment/challenge/gradlew
@@ -0,0 +1,234 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+APP_NAME="Gradle"
+APP_BASE_NAME=${0##*/}
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+# Collect all arguments for the java command;
+#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+#     shell script including quotes and variable substitutions, so put them in
+#     double quotes to make sure that they get re-expanded; and
+#   * put everything else in single quotes, so that it's not re-expanded.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"
diff --git a/backend/individual-assignment/challenge/gradlew.bat b/backend/individual-assignment/challenge/gradlew.bat
new file mode 100644
index 00000000..107acd32
--- /dev/null
+++ b/backend/individual-assignment/challenge/gradlew.bat
@@ -0,0 +1,89 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/backend/individual-assignment/challenge/settings.gradle.kts b/backend/individual-assignment/challenge/settings.gradle.kts
new file mode 100644
index 00000000..b4e2e9d6
--- /dev/null
+++ b/backend/individual-assignment/challenge/settings.gradle.kts
@@ -0,0 +1,5 @@
+plugins {
+    id("org.gradle.toolchains.foojay-resolver-convention") version "0.8.0"
+}
+rootProject.name = "challenge"
+
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/Main.kt b/backend/individual-assignment/challenge/src/main/kotlin/Main.kt
new file mode 100644
index 00000000..496d2331
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/Main.kt
@@ -0,0 +1,39 @@
+package org.example
+
+import org.example.dtos.Address
+import org.example.dtos.CreditCard
+import org.example.dtos.Customer
+import org.example.dtos.Product
+import org.example.enums.ProductType
+import org.example.models.impl.Order
+
+//TIP To <b>Run</b> code, press <shortcut actionId="Run"/> or
+// click the <icon src="AllIcons.Actions.Execute"/> icon in the gutter.
+fun main(args : Array<String>) {
+    val shirt = Product("Flowered t-shirt", ProductType.PHYSICAL, 35.00)
+    val netflix = Product("Familiar plan", ProductType.MEMBERSHIP, 29.90)
+    val book = Product("The Hitchhiker's Guide to the Galaxy", ProductType.BOOK, 120.00)
+    val music = Product("Stairway to Heaven", ProductType.DIGITAL, 5.00)
+
+    val order = Order(
+        Customer(
+            isMember = false,
+            email = "batatoncio.solanum-tuberosum@wilsomclaudio.com"
+        ),
+        Address(
+            street = "Here"
+        )
+    )
+
+    order.addProduct(shirt, 2)
+    order.addProduct(netflix, 1)
+    order.addProduct(book, 1)
+    order.addProduct(music, 1)
+
+    // In this scenario, we may use database instructions so that if the processProduct fail, the payment will rollback
+    order.pay(CreditCard("43567890-987654367"))
+
+    // Depending on how long does it take to some of these methods to be run, queue processors may be handy
+    // The carefulness needed is if process method throws something, so that a payment rollback will be needed
+    order.processProduct()
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/dtos/Address.kt b/backend/individual-assignment/challenge/src/main/kotlin/dtos/Address.kt
new file mode 100644
index 00000000..666d323a
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/dtos/Address.kt
@@ -0,0 +1,5 @@
+package org.example.dtos
+
+data class Address(
+    val street: String
+)
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/dtos/CreditCard.kt b/backend/individual-assignment/challenge/src/main/kotlin/dtos/CreditCard.kt
new file mode 100644
index 00000000..36dafa41
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/dtos/CreditCard.kt
@@ -0,0 +1,7 @@
+package org.example.dtos
+
+import org.example.models.PaymentMethod
+
+data class CreditCard(
+    val number: String
+) : PaymentMethod
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/dtos/Customer.kt b/backend/individual-assignment/challenge/src/main/kotlin/dtos/Customer.kt
new file mode 100644
index 00000000..fc1ff3bf
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/dtos/Customer.kt
@@ -0,0 +1,6 @@
+package org.example.dtos
+
+data class Customer (
+    val isMember: Boolean,
+    val email: String
+)
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/dtos/Invoice.kt b/backend/individual-assignment/challenge/src/main/kotlin/dtos/Invoice.kt
new file mode 100644
index 00000000..28211a33
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/dtos/Invoice.kt
@@ -0,0 +1,8 @@
+package org.example.dtos
+
+import org.example.models.impl.Order
+
+data class Invoice(val order: Order) {
+    val billingAddress: Address = order.address
+    val shippingAddress: Address = order.address
+}
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/dtos/OrderItem.kt b/backend/individual-assignment/challenge/src/main/kotlin/dtos/OrderItem.kt
new file mode 100644
index 00000000..1de15e21
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/dtos/OrderItem.kt
@@ -0,0 +1,8 @@
+package org.example.dtos
+
+data class OrderItem(
+    val product: Product,
+    val quantity: Int
+) {
+    val total get() = product.price * quantity
+}
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/dtos/Payment.kt b/backend/individual-assignment/challenge/src/main/kotlin/dtos/Payment.kt
new file mode 100644
index 00000000..079a323e
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/dtos/Payment.kt
@@ -0,0 +1,15 @@
+package org.example.dtos
+
+import org.example.models.PaymentMethod
+import org.example.models.impl.Order
+import java.util.*
+
+data class Payment(
+    val order: Order,
+    val paymentMethod: PaymentMethod
+) {
+    val paidAt = Date()
+    val authorizationNumber = paidAt.time
+    val amount = order.totalAmount
+    val invoice = Invoice(order)
+}
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/dtos/Product.kt b/backend/individual-assignment/challenge/src/main/kotlin/dtos/Product.kt
new file mode 100644
index 00000000..230cce2f
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/dtos/Product.kt
@@ -0,0 +1,9 @@
+package org.example.dtos
+
+import org.example.enums.ProductType
+
+data class Product(
+    val name: String,
+    val type: ProductType,
+    val price: Double
+)
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/dtos/Voucher.kt b/backend/individual-assignment/challenge/src/main/kotlin/dtos/Voucher.kt
new file mode 100644
index 00000000..63d6ec46
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/dtos/Voucher.kt
@@ -0,0 +1,5 @@
+package org.example.dtos
+
+data class Voucher(
+    val discountE4: Long
+)
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/enums/ProductType.kt b/backend/individual-assignment/challenge/src/main/kotlin/enums/ProductType.kt
new file mode 100644
index 00000000..22ec9656
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/enums/ProductType.kt
@@ -0,0 +1,8 @@
+package org.example.enums
+
+enum class ProductType {
+    PHYSICAL,
+    BOOK,
+    DIGITAL,
+    MEMBERSHIP
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/enums/Taxes.kt b/backend/individual-assignment/challenge/src/main/kotlin/enums/Taxes.kt
new file mode 100644
index 00000000..7a3ea5d8
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/enums/Taxes.kt
@@ -0,0 +1,5 @@
+package org.example.enums
+
+enum class Taxes {
+    SHIP_ART_150
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/extension/AddressExtensions.kt b/backend/individual-assignment/challenge/src/main/kotlin/extension/AddressExtensions.kt
new file mode 100644
index 00000000..95f4ba30
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/extension/AddressExtensions.kt
@@ -0,0 +1,10 @@
+package org.example.extension
+
+import org.example.dtos.Address
+
+fun Address.isValid(): Boolean {
+    if(this.street == "nowhere"){
+        return false
+    }
+    return true
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/extension/ProductTypeProcess.kt b/backend/individual-assignment/challenge/src/main/kotlin/extension/ProductTypeProcess.kt
new file mode 100644
index 00000000..2fee1e4b
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/extension/ProductTypeProcess.kt
@@ -0,0 +1,47 @@
+package org.example.extension
+
+import org.example.enums.Taxes
+import org.example.models.impl.*
+
+fun physicalProcess(
+    order: Order
+): String {
+    if(!order.address.isValid()){
+        throw Exception("Address not valid")
+    }
+    return ShippingLabelImpl().ship(
+        address = order.address,
+        customer = order.customer,
+        exemptTaxes = emptyList()
+    )
+}
+
+fun bookProcess(
+    order: Order
+): String {
+    return ShippingLabelImpl().ship(
+        address = order.address,
+        customer = order.customer,
+        exemptTaxes = listOf(Taxes.SHIP_ART_150)
+    )
+}
+
+fun digitalProcess(
+    order: Order
+): String {
+    return DigitalPurchaseImpl(
+        SendEmailImpl()
+    ).sendMailWithVoucher(
+        order.customer
+    )
+}
+
+fun membershipProcess(
+    order: Order
+): String {
+    return MembershipImpl(
+        SendEmailImpl()
+    ).activateMembership(
+        order.customer
+    )
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/models/DigitalPurchase.kt b/backend/individual-assignment/challenge/src/main/kotlin/models/DigitalPurchase.kt
new file mode 100644
index 00000000..4c687967
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/models/DigitalPurchase.kt
@@ -0,0 +1,7 @@
+package org.example.models
+
+import org.example.dtos.Customer
+
+interface DigitalPurchase{
+    fun sendMailWithVoucher(customer: Customer): String
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/models/Membership.kt b/backend/individual-assignment/challenge/src/main/kotlin/models/Membership.kt
new file mode 100644
index 00000000..6a03a577
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/models/Membership.kt
@@ -0,0 +1,7 @@
+package org.example.models
+
+import org.example.dtos.Customer
+
+interface Membership {
+    fun activateMembership(customer: Customer): String
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/models/PaymentMethod.kt b/backend/individual-assignment/challenge/src/main/kotlin/models/PaymentMethod.kt
new file mode 100644
index 00000000..607017aa
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/models/PaymentMethod.kt
@@ -0,0 +1,4 @@
+package org.example.models
+
+interface PaymentMethod {
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/models/SendEmail.kt b/backend/individual-assignment/challenge/src/main/kotlin/models/SendEmail.kt
new file mode 100644
index 00000000..7e3d16e1
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/models/SendEmail.kt
@@ -0,0 +1,10 @@
+package org.example.models
+
+import org.example.dtos.Voucher
+
+interface SendEmail {
+    fun sendEmail(
+        email: String,
+        voucher: Voucher? = null
+    ): String
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/models/ShippingLabel.kt b/backend/individual-assignment/challenge/src/main/kotlin/models/ShippingLabel.kt
new file mode 100644
index 00000000..507364a4
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/models/ShippingLabel.kt
@@ -0,0 +1,14 @@
+package org.example.models
+
+import org.example.dtos.Address
+import org.example.dtos.Customer
+import org.example.enums.Taxes
+
+interface ShippingLabel {
+    fun ship(
+        customer: Customer,
+        address: Address,
+        exemptTaxes: List<Taxes>
+    ): String
+}
+
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/models/impl/DigitalPurchaseImpl.kt b/backend/individual-assignment/challenge/src/main/kotlin/models/impl/DigitalPurchaseImpl.kt
new file mode 100644
index 00000000..db4d054f
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/models/impl/DigitalPurchaseImpl.kt
@@ -0,0 +1,25 @@
+package org.example.models.impl
+
+import org.example.dtos.Voucher
+import org.example.dtos.Customer
+import org.example.models.DigitalPurchase
+import org.example.models.SendEmail
+
+class DigitalPurchaseImpl(
+    val emailSender : SendEmail
+): DigitalPurchase {
+    override fun sendMailWithVoucher(customer: Customer): String{
+        emailSender.sendEmail(
+            customer.email,
+            defaultVaucher
+        )
+
+        return "The customer received a email with voucher"
+    }
+
+    companion object{
+        private val defaultVaucher = Voucher(
+            discountE4 = 1000
+        )
+    }
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/models/impl/MembershipImpl.kt b/backend/individual-assignment/challenge/src/main/kotlin/models/impl/MembershipImpl.kt
new file mode 100644
index 00000000..d59525da
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/models/impl/MembershipImpl.kt
@@ -0,0 +1,25 @@
+package org.example.models.impl
+
+import org.example.dtos.Voucher
+import org.example.dtos.Customer
+import org.example.models.Membership
+import org.example.models.SendEmail
+
+class MembershipImpl(
+    val emailSender : SendEmail
+): Membership {
+
+    override fun activateMembership(customer: Customer): String {
+        if(customer.isMember) {
+            println("The member is already a member, the expirationDate will be increased")
+            return "The member is already a member, the expirationDate will be increased"
+        } else {
+            println("The client will have his membership activated")
+            emailSender.sendEmail(
+                email = customer.email
+            )
+
+            return "The Customer is now a member"
+        }
+    }
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/models/impl/Order.kt b/backend/individual-assignment/challenge/src/main/kotlin/models/impl/Order.kt
new file mode 100644
index 00000000..ffbadff9
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/models/impl/Order.kt
@@ -0,0 +1,72 @@
+package org.example.models.impl
+
+import org.example.dtos.*
+import org.example.enums.*
+import org.example.extension.bookProcess
+import org.example.extension.digitalProcess
+import org.example.extension.membershipProcess
+import org.example.extension.physicalProcess
+import org.example.models.PaymentMethod
+import java.util.*
+
+class Order(
+    val customer: Customer,
+    val address: Address
+) {
+    private val items = mutableListOf<OrderItem>()
+    var closedAt: Date? = null
+        private set
+    var payment: Payment? = null
+        private set
+    val totalAmount
+        get() = items.sumOf { it.total }
+
+    fun addProduct(
+        product: Product,
+        quantity: Int
+    ) {
+        val productAlreadyAdded = items.any { it.product == product }
+        if (productAlreadyAdded)
+            throw Exception("The product have already been added. Change the amount if you want more.")
+
+        items.add(OrderItem(product, quantity))
+    }
+
+    fun pay(method: PaymentMethod) {
+        if (payment != null) {
+            throw Exception("The order has already been paid!")
+        }
+
+        if (items.isEmpty()) {
+            throw Exception("Empty order can not be paid!")
+        }
+
+        payment = Payment(this, method)
+
+        close()
+    }
+
+    fun processProduct() {
+        items.forEach{
+            item ->
+            when(item.product.type) {
+                ProductType.BOOK -> bookProcess(
+                    order = this
+                )
+                ProductType.PHYSICAL -> physicalProcess(
+                    order = this
+                )
+                ProductType.DIGITAL -> digitalProcess(
+                    order = this
+                )
+                ProductType.MEMBERSHIP -> membershipProcess(
+                    order = this
+                )
+            }
+        }
+    }
+
+    private fun close() {
+        closedAt = Date()
+    }
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/models/impl/SendEmailImpl.kt b/backend/individual-assignment/challenge/src/main/kotlin/models/impl/SendEmailImpl.kt
new file mode 100644
index 00000000..2af8109c
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/models/impl/SendEmailImpl.kt
@@ -0,0 +1,14 @@
+package org.example.models.impl
+
+import org.example.dtos.Voucher
+import org.example.models.SendEmail
+
+class SendEmailImpl: SendEmail {
+    override fun sendEmail(
+        email: String,
+        voucher: Voucher?
+    ): String {
+        println("Method that will make email body, with whatever tool")
+        return "Method that will make email body, with whatever tool"
+    }
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/main/kotlin/models/impl/ShippingLabelImpl.kt b/backend/individual-assignment/challenge/src/main/kotlin/models/impl/ShippingLabelImpl.kt
new file mode 100644
index 00000000..080e0d17
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/main/kotlin/models/impl/ShippingLabelImpl.kt
@@ -0,0 +1,22 @@
+package org.example.models.impl
+
+import org.example.enums.Taxes
+import org.example.dtos.Address
+import org.example.dtos.Customer
+import org.example.models.ShippingLabel
+
+class ShippingLabelImpl: ShippingLabel {
+    override fun ship(
+        customer: Customer,
+        address: Address,
+        exemptTaxes: List<Taxes>
+    ): String {
+        if(exemptTaxes.isEmpty()){
+            println("The object was shipped with taxes")
+            return "The object was shipped with taxes"
+        } else {
+            println("The object was shipped with NO taxes")
+            return "The object was shipped with NO taxes"
+        }
+    }
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/test/kotlin/DigitalPurchaseTest.kt b/backend/individual-assignment/challenge/src/test/kotlin/DigitalPurchaseTest.kt
new file mode 100644
index 00000000..008b4ea4
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/test/kotlin/DigitalPurchaseTest.kt
@@ -0,0 +1,54 @@
+import fixtures.CustomerFixture
+import org.example.models.impl.DigitalPurchaseImpl
+import org.example.models.impl.SendEmailImpl
+import org.junit.jupiter.api.Test
+import kotlin.test.assertEquals
+
+class DigitalPurchaseTest {
+    //Other classes will not be tested due to time limit...
+    val emailSenderMockk = SendEmailImpl() // This was supposed to be mockk<SendEmail>()
+    val digitalImpl = DigitalPurchaseImpl(emailSenderMockk)
+
+    @Test
+    fun `(sendEmail) Shall send email with voucher`(){
+        val customer = CustomerFixture().customer
+
+        /*
+        every {
+            emailSenderMockk.sendEmail()
+        } returns "success"
+         */
+
+        val response = digitalImpl.sendMailWithVoucher(
+            customer = customer
+        )
+
+        assertEquals("The customer received a email with voucher",response)
+    }
+
+    @Test
+    fun `(sendEmail) Rethrow error if emailSender throws`(){
+        val customer = CustomerFixture().customer
+
+
+        /*
+        every {
+            emailSenderMockk.sendEmail()
+        } throws Exception("Fon")
+         */
+
+        /*
+            assertFail when calling sendMailWithVoucher
+         */
+
+        val response = digitalImpl.sendMailWithVoucher(
+            customer = customer
+        )
+
+        /*
+         Would Assert message and exception type
+         */
+
+        assertEquals(true, true)
+    }
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/test/kotlin/ProductTypeProcessTest.kt b/backend/individual-assignment/challenge/src/test/kotlin/ProductTypeProcessTest.kt
new file mode 100644
index 00000000..f9d61531
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/test/kotlin/ProductTypeProcessTest.kt
@@ -0,0 +1,71 @@
+import fixtures.OrderFixture
+import org.example.extension.bookProcess
+import org.example.extension.digitalProcess
+import org.example.extension.membershipProcess
+import org.example.extension.physicalProcess
+import org.junit.jupiter.api.Order
+import org.junit.jupiter.api.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFails
+import kotlin.test.assertFailsWith
+import kotlin.test.assertTrue
+
+class ProductTypeProcessTest {
+    private val order = OrderFixture().order
+
+    @Test
+    fun `(physicalProcess) Shall ship the object with the taxes`(){
+        val response = physicalProcess(order)
+
+        assertEquals("The object was shipped with taxes", response)
+    }
+
+    @Test
+    fun `(physicalProcess) Shall throw exception if Address is not valid`(){
+        val order = OrderFixture().invalidAddressOrder
+        val response = assertFailsWith<Exception>{
+            physicalProcess(order)
+        }
+
+        assertEquals("Address not valid", response.message)
+    }
+
+    @Test
+    fun `(bookProcess) Shall ship the object without taxes`(){
+        val response = bookProcess(order)
+
+        assertEquals("The object was shipped with NO taxes", response)
+    }
+
+    @Test
+    fun `(digitalProcess) Shall send email with voucher`(){
+        val response = digitalProcess(order)
+
+        assertEquals("The customer received a email with voucher",response)
+    }
+
+    @Test
+    fun `(membershipProcess) Shall make the Customer a member`(){
+        val response = membershipProcess(order)
+
+        assertEquals("The Customer is now a member", response)
+    }
+
+    @Test
+    fun `(membershipProcess) Shall extend the Customer membership if hes already a member`(){
+        val order = OrderFixture().memberOrder
+
+        val response = membershipProcess(order)
+
+        assertEquals("The member is already a member, the expirationDate will be increased", response)
+    }
+
+    @Test
+    fun `(membershipProcess) rethrow error if MembershipImpl has any error`(){
+        //This case would mockkStatic the Membership, and make every activateMembership throws error
+        // Need to import it, but will not
+        // All methods that may be mocked would have a method like this, so that it will make its own test
+        // an UNIT test...
+        assertTrue(true)
+    }
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/test/kotlin/fixtures/AddressFixture.kt b/backend/individual-assignment/challenge/src/test/kotlin/fixtures/AddressFixture.kt
new file mode 100644
index 00000000..68b9ff70
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/test/kotlin/fixtures/AddressFixture.kt
@@ -0,0 +1,13 @@
+package fixtures
+
+import org.example.dtos.Address
+
+class AddressFixture {
+    val address = Address(
+        street = "somewhere"
+    )
+
+    val invalidAddress = Address(
+        street = "nowhere"
+    )
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/test/kotlin/fixtures/CustomerFixture.kt b/backend/individual-assignment/challenge/src/test/kotlin/fixtures/CustomerFixture.kt
new file mode 100644
index 00000000..eb845eec
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/test/kotlin/fixtures/CustomerFixture.kt
@@ -0,0 +1,15 @@
+package fixtures
+
+import org.example.dtos.Customer
+
+class CustomerFixture{
+    val customer = Customer(
+        isMember = false,
+        email = "batata@gmail.com"
+    )
+
+    val nonMemberCustomer = Customer(
+        isMember = true,
+        email = "batata@gmail.com"
+    )
+}
\ No newline at end of file
diff --git a/backend/individual-assignment/challenge/src/test/kotlin/fixtures/OrderFixture.kt b/backend/individual-assignment/challenge/src/test/kotlin/fixtures/OrderFixture.kt
new file mode 100644
index 00000000..6788bae6
--- /dev/null
+++ b/backend/individual-assignment/challenge/src/test/kotlin/fixtures/OrderFixture.kt
@@ -0,0 +1,20 @@
+package fixtures
+
+import org.example.models.impl.Order
+
+class OrderFixture {
+    val order = Order(
+        customer = CustomerFixture().customer,
+        address = AddressFixture().address
+    )
+
+    val memberOrder = Order(
+        customer = CustomerFixture().nonMemberCustomer,
+        address = AddressFixture().address
+    )
+
+    val invalidAddressOrder = Order(
+        customer = CustomerFixture().nonMemberCustomer,
+        address = AddressFixture().invalidAddress
+    )
+}
\ No newline at end of file