diff --git a/source/Calamari.Aws/Calamari.Aws.csproj b/source/Calamari.Aws/Calamari.Aws.csproj
index 435e3e63b5..1254aaffb4 100644
--- a/source/Calamari.Aws/Calamari.Aws.csproj
+++ b/source/Calamari.Aws/Calamari.Aws.csproj
@@ -20,6 +20,7 @@
     <StartupObject />
     <TargetFramework>net8.0</TargetFramework>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="AWSSDK.ECS" Version="4.0.19" />
diff --git a/source/Calamari.Azure/Calamari.Azure.csproj b/source/Calamari.Azure/Calamari.Azure.csproj
index 35b6599c7f..8397e954de 100644
--- a/source/Calamari.Azure/Calamari.Azure.csproj
+++ b/source/Calamari.Azure/Calamari.Azure.csproj
@@ -7,6 +7,7 @@
         <Copyright>Octopus Deploy Pty Ltd</Copyright>
         <TargetFramework>net8.0</TargetFramework>
         <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+        <Nullable>enable</Nullable>
     </PropertyGroup>
     <ItemGroup>
         <PackageReference Include="Azure.Identity" Version="1.13.1" />
diff --git a/source/Calamari.AzureAppService.Tests/Calamari.AzureAppService.Tests.csproj b/source/Calamari.AzureAppService.Tests/Calamari.AzureAppService.Tests.csproj
index 7ef8b53374..0bcfe33c18 100644
--- a/source/Calamari.AzureAppService.Tests/Calamari.AzureAppService.Tests.csproj
+++ b/source/Calamari.AzureAppService.Tests/Calamari.AzureAppService.Tests.csproj
@@ -7,6 +7,7 @@
     <RuntimeIdentifiers>win-x64;linux-x64;osx-x64;linux-arm;linux-arm64</RuntimeIdentifiers>
     <TargetFramework>net8.0</TargetFramework>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/source/Calamari.AzureAppService/Calamari.AzureAppService.csproj b/source/Calamari.AzureAppService/Calamari.AzureAppService.csproj
index 3c6b81a176..b09bfa5628 100644
--- a/source/Calamari.AzureAppService/Calamari.AzureAppService.csproj
+++ b/source/Calamari.AzureAppService/Calamari.AzureAppService.csproj
@@ -10,6 +10,7 @@
     <NoWarn>NU5104</NoWarn>
     <TargetFramework>net8.0</TargetFramework>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="Azure.ResourceManager.AppService" Version="1.0.2" />
diff --git a/source/Calamari.AzureResourceGroup.Tests/Calamari.AzureResourceGroup.Tests.csproj b/source/Calamari.AzureResourceGroup.Tests/Calamari.AzureResourceGroup.Tests.csproj
index 55a49cc53c..a86b307cc1 100644
--- a/source/Calamari.AzureResourceGroup.Tests/Calamari.AzureResourceGroup.Tests.csproj
+++ b/source/Calamari.AzureResourceGroup.Tests/Calamari.AzureResourceGroup.Tests.csproj
@@ -6,6 +6,7 @@
     <RuntimeIdentifiers>win-x64;linux-x64;osx-x64;linux-arm;linux-arm64</RuntimeIdentifiers>
     <TargetFramework>net8.0</TargetFramework>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="nunit" Version="3.14.0" />
diff --git a/source/Calamari.AzureServiceFabric.Tests/Calamari.AzureServiceFabric.Tests.csproj b/source/Calamari.AzureServiceFabric.Tests/Calamari.AzureServiceFabric.Tests.csproj
index e383bd00be..efc8752dcb 100644
--- a/source/Calamari.AzureServiceFabric.Tests/Calamari.AzureServiceFabric.Tests.csproj
+++ b/source/Calamari.AzureServiceFabric.Tests/Calamari.AzureServiceFabric.Tests.csproj
@@ -7,6 +7,7 @@
         <TargetFramework>net8.0-windows</TargetFramework>
         <RuntimeIdentifiers>win-x64</RuntimeIdentifiers>
         <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+        <Nullable>enable</Nullable>
     </PropertyGroup>
     <ItemGroup>
         <PackageReference Include="FluentAssertions" Version="7.2.0" />
diff --git a/source/Calamari.AzureWebApp.Tests/Calamari.AzureWebApp.Tests.csproj b/source/Calamari.AzureWebApp.Tests/Calamari.AzureWebApp.Tests.csproj
index 0b6a698239..e5f8a14cb5 100644
--- a/source/Calamari.AzureWebApp.Tests/Calamari.AzureWebApp.Tests.csproj
+++ b/source/Calamari.AzureWebApp.Tests/Calamari.AzureWebApp.Tests.csproj
@@ -6,6 +6,7 @@
     <RuntimeIdentifiers>win-x64</RuntimeIdentifiers>
     <IsPackable>false</IsPackable>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="nunit" Version="3.14.0" />
diff --git a/source/Calamari.AzureWebApp/Calamari.AzureWebApp.csproj b/source/Calamari.AzureWebApp/Calamari.AzureWebApp.csproj
index 05304d5f16..626ca33b51 100644
--- a/source/Calamari.AzureWebApp/Calamari.AzureWebApp.csproj
+++ b/source/Calamari.AzureWebApp/Calamari.AzureWebApp.csproj
@@ -5,10 +5,11 @@
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
     <IsPackable>false</IsPackable>
     <OutputType>Exe</OutputType>
-    <LangVersion>8.0</LangVersion>
+    <LangVersion>12</LangVersion>
     <TargetFramework>net8.0</TargetFramework>
     <RuntimeIdentifiers>win-x64</RuntimeIdentifiers>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
 
 
diff --git a/source/Calamari.CloudAccounts/Calamari.CloudAccounts.csproj b/source/Calamari.CloudAccounts/Calamari.CloudAccounts.csproj
index 535418a116..09f5cddb1f 100644
--- a/source/Calamari.CloudAccounts/Calamari.CloudAccounts.csproj
+++ b/source/Calamari.CloudAccounts/Calamari.CloudAccounts.csproj
@@ -11,6 +11,7 @@
         <PackageLicenseUrl>https://github.com/OctopusDeploy/Calamari/blob/main/LICENSE.txt</PackageLicenseUrl>
         <RepositoryUrl>https://github.com/OctopusDeploy/Calamari</RepositoryUrl>
         <RepositoryType>git</RepositoryType>
+        <Nullable>enable</Nullable>
     </PropertyGroup>
 
     <ItemGroup>
diff --git a/source/Calamari.ConsolidateCalamariPackages.Tests/Calamari.ConsolidateCalamariPackages.Tests.csproj b/source/Calamari.ConsolidateCalamariPackages.Tests/Calamari.ConsolidateCalamariPackages.Tests.csproj
index a2ff998be7..139378c0a2 100644
--- a/source/Calamari.ConsolidateCalamariPackages.Tests/Calamari.ConsolidateCalamariPackages.Tests.csproj
+++ b/source/Calamari.ConsolidateCalamariPackages.Tests/Calamari.ConsolidateCalamariPackages.Tests.csproj
@@ -4,6 +4,7 @@
         <TargetFramework>net8.0</TargetFramework>
         <IsPackable>false</IsPackable>
         <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+        <Nullable>enable</Nullable>
     </PropertyGroup>
 
     <ItemGroup>
diff --git a/source/Calamari.ConsolidateCalamariPackages/Calamari.ConsolidateCalamariPackages.csproj b/source/Calamari.ConsolidateCalamariPackages/Calamari.ConsolidateCalamariPackages.csproj
index ee3cc2d8a8..61b1c1e59a 100644
--- a/source/Calamari.ConsolidateCalamariPackages/Calamari.ConsolidateCalamariPackages.csproj
+++ b/source/Calamari.ConsolidateCalamariPackages/Calamari.ConsolidateCalamariPackages.csproj
@@ -15,6 +15,7 @@
             into a single archive.
         </Description>
         <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+        <Nullable>enable</Nullable>
     </PropertyGroup>
     <ItemGroup>
       <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
diff --git a/source/Calamari.GoogleCloudAccounts/Calamari.GoogleCloudAccounts.csproj b/source/Calamari.GoogleCloudAccounts/Calamari.GoogleCloudAccounts.csproj
index 012535291a..911045c1ba 100644
--- a/source/Calamari.GoogleCloudAccounts/Calamari.GoogleCloudAccounts.csproj
+++ b/source/Calamari.GoogleCloudAccounts/Calamari.GoogleCloudAccounts.csproj
@@ -6,6 +6,7 @@
         <!-- CS8632: The annotation for nullable reference types should only be used in code within a '#nullable' annotations context. -->
         <NoWarn>CS8632</NoWarn>
         <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+        <Nullable>enable</Nullable>
     </PropertyGroup>
 
     <ItemGroup>
diff --git a/source/Calamari.GoogleCloudScripting/Calamari.GoogleCloudScripting.csproj b/source/Calamari.GoogleCloudScripting/Calamari.GoogleCloudScripting.csproj
index 2a2a3858b3..91b90efb9e 100644
--- a/source/Calamari.GoogleCloudScripting/Calamari.GoogleCloudScripting.csproj
+++ b/source/Calamari.GoogleCloudScripting/Calamari.GoogleCloudScripting.csproj
@@ -10,6 +10,7 @@
         <!-- CS8632: The annotation for nullable reference types should only be used in code within a '#nullable' annotations context. -->
         <NoWarn>CS8632</NoWarn>
         <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+        <Nullable>enable</Nullable>
     </PropertyGroup>
 
     <ItemGroup>
diff --git a/source/Calamari.Scripting.Tests/Calamari.Scripting.Tests.csproj b/source/Calamari.Scripting.Tests/Calamari.Scripting.Tests.csproj
index 90f74af71d..2a57be42d8 100644
--- a/source/Calamari.Scripting.Tests/Calamari.Scripting.Tests.csproj
+++ b/source/Calamari.Scripting.Tests/Calamari.Scripting.Tests.csproj
@@ -6,6 +6,7 @@
         <RuntimeIdentifiers>win-x64;linux-x64;osx-x64;linux-arm;linux-arm64</RuntimeIdentifiers>
         <IsPackable>false</IsPackable>
         <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+        <Nullable>enable</Nullable>
     </PropertyGroup>
     <ItemGroup>
         <PackageReference Include="FluentAssertions" Version="7.2.0" />
diff --git a/source/Calamari.Terraform.Tests/Calamari.Terraform.Tests.csproj b/source/Calamari.Terraform.Tests/Calamari.Terraform.Tests.csproj
index 6ebeb461d0..e34c3f00a8 100644
--- a/source/Calamari.Terraform.Tests/Calamari.Terraform.Tests.csproj
+++ b/source/Calamari.Terraform.Tests/Calamari.Terraform.Tests.csproj
@@ -9,6 +9,7 @@
         <!-- CS8632: The annotation for nullable reference types should only be used in code within a '#nullable' annotations context. -->
         <NoWarn>CS8632</NoWarn>
         <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+        <Nullable>enable</Nullable>
     </PropertyGroup>
     <ItemGroup>
         <PackageReference Include="FluentAssertions" Version="7.2.0" />
diff --git a/source/Calamari.Terraform/Calamari.Terraform.csproj b/source/Calamari.Terraform/Calamari.Terraform.csproj
index f06bb292ec..cb714d0855 100644
--- a/source/Calamari.Terraform/Calamari.Terraform.csproj
+++ b/source/Calamari.Terraform/Calamari.Terraform.csproj
@@ -8,6 +8,7 @@
     <RuntimeIdentifiers>win-x64;linux-x64;osx-x64;linux-arm;linux-arm64</RuntimeIdentifiers>
     <TargetFramework>net8.0</TargetFramework>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="NuGet.Versioning" Version="7.4.0-octopus-release.17001" />
diff --git a/source/Calamari.Tests/Calamari.Tests.csproj b/source/Calamari.Tests/Calamari.Tests.csproj
index 388a077038..00f4a0c7c3 100644
--- a/source/Calamari.Tests/Calamari.Tests.csproj
+++ b/source/Calamari.Tests/Calamari.Tests.csproj
@@ -13,6 +13,7 @@
         <TargetFramework>net8.0</TargetFramework>
         <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
         <EmitLegacyAssetsFileItems>true</EmitLegacyAssetsFileItems>
+        <Nullable>enable</Nullable>
     </PropertyGroup>
     <ItemGroup>
         <PackageReference Include="Microsoft.Extensions.TimeProvider.Testing" Version="10.4.0" />
diff --git a/source/Calamari/Calamari.csproj b/source/Calamari/Calamari.csproj
index d8ed4ff0ab..c473527e9c 100644
--- a/source/Calamari/Calamari.csproj
+++ b/source/Calamari/Calamari.csproj
@@ -22,6 +22,7 @@
     <!-- CS8632: The annotation for nullable reference types should only be used in code within a '#nullable' annotations context. -->
     <NoWarn>CS8632</NoWarn>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
   <ItemGroup>
     <ProjectReference Include="..\Calamari.Aws\Calamari.Aws.csproj" />