From 9a609bf08ac1b6157dbdfb827fc01e771d71262e Mon Sep 17 00:00:00 2001
From: Ruben Fiszel <ruben@windmill.dev>
Date: Fri, 5 Jun 2026 11:43:40 +0200
Subject: [PATCH] feat: make C# dotnet target framework configurable via
 DOTNET_TARGET_FRAMEWORK (#9454)

* feat: make C# dotnet target framework configurable via DOTNET_TARGET_FRAMEWORK

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* fix: include dotnet target framework in C# binary cache key

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---
 backend/windmill-worker/src/csharp_executor.rs | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/backend/windmill-worker/src/csharp_executor.rs b/backend/windmill-worker/src/csharp_executor.rs
index 70df9fb4e0..944236cf2b 100644
--- a/backend/windmill-worker/src/csharp_executor.rs
+++ b/backend/windmill-worker/src/csharp_executor.rs
@@ -56,9 +56,13 @@ const DOTNET_ROOT_DEFAULT: &str = "C:\\Program Files\\dotnet";
 #[cfg(unix)]
 const DOTNET_ROOT_DEFAULT: &str = "/usr/share/dotnet";
 
+#[cfg(feature = "csharp")]
+const DOTNET_TARGET_FRAMEWORK_DEFAULT: &str = "net9.0";
+
 #[cfg(feature = "csharp")]
 lazy_static::lazy_static! {
     static ref DOTNET_ROOT: String = std::env::var("DOTNET_ROOT").unwrap_or_else(|_| DOTNET_ROOT_DEFAULT.to_string());
+    static ref DOTNET_TARGET_FRAMEWORK: String = std::env::var("DOTNET_TARGET_FRAMEWORK").unwrap_or_else(|_| DOTNET_TARGET_FRAMEWORK_DEFAULT.to_string());
 }
 
 #[cfg(feature = "csharp")]
@@ -212,6 +216,7 @@ fn gen_cs_proj(
         )
     };
 
+    let target_framework = DOTNET_TARGET_FRAMEWORK.as_str();
     write_file(
         job_dir,
         "Main.csproj",
@@ -219,7 +224,7 @@ fn gen_cs_proj(
             r#"<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net9.0</TargetFramework>
+    <TargetFramework>{target_framework}</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <StartupObject>WindmillScriptCSharpInternal.Wrapper</StartupObject>
     <RestorePackagesWithLockFile>true</RestorePackagesWithLockFile>
@@ -510,9 +515,10 @@ pub async fn handle_csharp_job(
 
     let ws_suffix = crate::workspace_registry_cache_suffix(&job.workspace_id).await;
     let mut hash = calculate_hash(&format!(
-        "{}{}",
+        "{}{}{}",
         inner_content,
-        requirements_o.unwrap_or(&String::new())
+        requirements_o.unwrap_or(&String::new()),
+        DOTNET_TARGET_FRAMEWORK.as_str()
     ));
     hash.push_str(&ws_suffix);
     let bin_path = format!("{}/{hash}", *CSHARP_CACHE_DIR);