diff --git a/common-client/src/main/kotlin/BackendService.kt b/common-client/src/main/kotlin/BackendService.kt
new file mode 100644
index 0000000..1e0c113
--- /dev/null
+++ b/common-client/src/main/kotlin/BackendService.kt
@@ -0,0 +1,3 @@
+object BackendService {
+
+}
\ No newline at end of file
diff --git a/common/build.gradle b/common/build.gradle
index 68f3cda..830d908 100644
--- a/common/build.gradle
+++ b/common/build.gradle
@@ -7,3 +7,12 @@ dependencies {
     testCompile "org.jetbrains.kotlin:kotlin-test-annotations-common"
     testCompile "org.jetbrains.kotlin:kotlin-test-common"
 }
+
+compileKotlinCommon {
+    kotlinOptions {
+        freeCompilerArgs = [
+                "-Xuse-experimental=kotlin.Experimental",
+                "-Xuse-experimental=kotlin.ExperimentalMultiplatform"
+        ]
+    }
+}
\ No newline at end of file
diff --git a/common/src/main/kotlin/edu/unito/klinika/annotations/Annotations.kt b/common/src/main/kotlin/edu/unito/klinika/annotations/Annotations.kt
new file mode 100644
index 0000000..a9d77a7
--- /dev/null
+++ b/common/src/main/kotlin/edu/unito/klinika/annotations/Annotations.kt
@@ -0,0 +1,13 @@
+package edu.unito.klinika.annotations
+
+@UseExperimental(ExperimentalMultiplatform::class)
+@OptionalExpectation
+expect annotation class Entity()
+
+@UseExperimental(ExperimentalMultiplatform::class)
+@OptionalExpectation
+expect annotation class Id()
+
+@UseExperimental(ExperimentalMultiplatform::class)
+@OptionalExpectation
+expect annotation class GeneratedValue()
\ No newline at end of file
diff --git a/common/src/main/kotlin/edu/unito/klinika/data/Data.kt b/common/src/main/kotlin/edu/unito/klinika/data/Data.kt
new file mode 100644
index 0000000..88259dc
--- /dev/null
+++ b/common/src/main/kotlin/edu/unito/klinika/data/Data.kt
@@ -0,0 +1,8 @@
+package edu.unito.klinika.data
+
+import edu.unito.klinika.annotations.Entity
+import edu.unito.klinika.annotations.GeneratedValue
+import edu.unito.klinika.annotations.Id
+
+@Entity
+class User(@Id @GeneratedValue val id: Long, val name: String)
\ No newline at end of file
diff --git a/server/build.gradle b/server/build.gradle
index 114c4b6..aa74bd5 100644
--- a/server/build.gradle
+++ b/server/build.gradle
@@ -24,8 +24,14 @@ dependencies {
 
 compileKotlin {
     kotlinOptions.jvmTarget = '1.8'
+    kotlinOptions {
+        freeCompilerArgs = ['-Xuse-experimental=kotlin.Experimental']
+    }
 }
 compileTestKotlin {
     kotlinOptions.jvmTarget = '1.8'
+    kotlinOptions {
+        freeCompilerArgs = ['-Xuse-experimental=kotlin.Experimental']
+    }
 }
 sourceCompatibility = '1.8'
\ No newline at end of file
diff --git a/server/src/main/kotlin/edu/unito/klinika/Main.kt b/server/src/main/kotlin/edu/unito/klinika/Main.kt
index 88cb613..04a43cc 100644
--- a/server/src/main/kotlin/edu/unito/klinika/Main.kt
+++ b/server/src/main/kotlin/edu/unito/klinika/Main.kt
@@ -1,11 +1,15 @@
 package edu.unito.klinika
 
 import org.springframework.boot.autoconfigure.SpringBootApplication
+import org.springframework.boot.autoconfigure.domain.EntityScan
 import org.springframework.boot.runApplication
 
+
 @SpringBootApplication
 class KlinikaApplication
 
 fun main(args: Array<String>) {
     runApplication<KlinikaApplication>(*args)
 }
+
+
diff --git a/server/src/main/kotlin/edu/unito/klinika/annotations/Annotations.kt b/server/src/main/kotlin/edu/unito/klinika/annotations/Annotations.kt
new file mode 100644
index 0000000..c557b12
--- /dev/null
+++ b/server/src/main/kotlin/edu/unito/klinika/annotations/Annotations.kt
@@ -0,0 +1,10 @@
+package edu.unito.klinika.annotations
+
+import javax.persistence.Entity
+import javax.persistence.GeneratedValue
+import javax.persistence.Id
+
+actual typealias Entity = Entity
+actual typealias Id = Id
+actual typealias GeneratedValue = GeneratedValue
+