dotnet10: not possible to run dotnet9 projects (can't find net core app 9)

[gaelj]

Nixpkgs version

• Unstable (25.11)

Describe the bug

Since I added dotnet 10 (SDK, runtime and aspnetcore) to my dotnet-combined package, I can run projects targeting dotnet 10. But if I try to run a project targetting dotnet 9, I get this error

You must install or update .NET to run this application.

App: /home/gaj/.nuget/packages/swashbuckle.aspnetcore.cli/9.0.6/tools/net9.0/any/dotnet-swagger.dll
Architecture: x64
Framework: 'Microsoft.NETCore.App', version '9.0.0' (x64)
.NET location: /nix/store/9pa71r5z5sw8z63x1ci4s08b9bj22cz5-dotnet-sdk-10.0.100/share/dotnet/

The following frameworks were found:
  10.0.0 at [/nix/store/9pa71r5z5sw8z63x1ci4s08b9bj22cz5-dotnet-sdk-10.0.100/share/dotnet/shared/Microsoft.NETCore.App]

My dotnet combined package is defined as

with pkgs.dotnetCorePackages;
    combinePackages [
      runtime_6_0-bin
      runtime_7_0-bin
      runtime_8_0-bin
      runtime_9_0-bin
      runtime_10_0-bin
      aspnetcore_6_0-bin
      aspnetcore_7_0-bin
      aspnetcore_8_0-bin
      aspnetcore_9_0-bin
      aspnetcore_10_0-bin
      #sdk_9_0-bin
      sdk_10_0-bin
      pkgs.openldap
  ]

Before upgrading to dotnet10, so, with dotnet 9 SDK, there was no problem running projects targetting older frameworks.

Steps to reproduce

Use the combined net core packages described above. Create a dotnet project targeting dotnet 9. Try to run the project.

Expected behaviour

The correct dotnet9 binary should be found and the project should run

Screenshots

No response

Relevant log output

Additional context

No response

System metadata

• system: "x86_64-linux"
• host os: Linux 6.17.8, NixOS, 25.11 (Xantusia), 25.11.20251122.1c69805
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.31.2
• nixpkgs: /nix/store/h1hadfn6kxjaan80vy4k78iwsnqhhd72-source

Notify maintainers

@corngood

---

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I assert that this issue is relevant for Nixpkgs

• I assert that this is a bug and not a support request.
• I assert that this is not a duplicate of an existing issue.
• I assert that I have read the NixOS Code of Conduct and agree to abide by it.

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[corngood]

Can you provide a test case for this? Also, combinePackages is only meant to work with dotnet packages. Putting openldap in there is strange.

[gaelj]

oh sure - openldap has no place there. I removed it from my config, but I still get the problem.

To reproduce, open a terminal with SDK10 and run:

dotnet new console -n Test
cd Test

dotnet run # this works

sed -i 's/net10.0/net9.0/g' Test.csproj # replace TargetFramework attribute
rm -rf bin obj
dotnet run

gives me:

You must install or update .NET to run this application.

App: /home/gaj/test/Test/bin/Debug/net9.0/Test
Architecture: x64
Framework: 'Microsoft.NETCore.App', version '9.0.0' (x64)
.NET location: /nix/store/9pa71r5z5sw8z63x1ci4s08b9bj22cz5-dotnet-sdk-10.0.100/share/dotnet

The following frameworks were found:
  10.0.0 at [/nix/store/9pa71r5z5sw8z63x1ci4s08b9bj22cz5-dotnet-sdk-10.0.100/share/dotnet/shared/Microsoft.NETCore.App]

Learn more:
https://aka.ms/dotnet/app-launch-failed

To install missing framework, download:
https://aka.ms/dotnet-core-applaunch?framework=Microsoft.NETCore.App&framework_version=9.0.0&arch=x64&rid=linux-x64&os=nixos.25.11

If I open a dev shell with my pre-dotnet10 combined packages then dotnet 9 as well as dotnet 8 projects both run.

with pkgs.dotnetCorePackages;
    combinePackages [
      runtime_6_0-bin
      runtime_7_0-bin
      runtime_8_0-bin
      runtime_9_0-bin
      aspnetcore_6_0-bin
      aspnetcore_7_0-bin
      aspnetcore_8_0-bin
      aspnetcore_9_0-bin
      sdk_9_0-bin
  ]

dotnet --info in my dotnet9 shell:

.NET SDK:
 Version:           9.0.307
 Commit:            3bc3012cf9
 Workload version:  9.0.300-manifests.7913fe7a
 MSBuild version:   17.14.28+09c1be848

Runtime Environment:
 OS Name:     nixos
 OS Version:  25.11
 OS Platform: Linux
 RID:         linux-x64
 Base Path:   /nix/store/0rikqcq1a8icaivbsqbgfl0d8sypvc2q-dotnet-sdk-9.0.307/share/dotnet/sdk/9.0.307/

.NET workloads installed:
There are no installed workloads to display.
Configured to use loose manifests when installing new manifests.

Host:
  Version:      9.0.11
  Architecture: x64
  Commit:       fa7cdded37

.NET SDKs installed:
  9.0.307 [/nix/store/06l7idpgs2z417m93zx57bgin9rk4ydh-dotnet-combined/share/dotnet/sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 6.0.36 [/nix/store/06l7idpgs2z417m93zx57bgin9rk4ydh-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 7.0.20 [/nix/store/06l7idpgs2z417m93zx57bgin9rk4ydh-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 8.0.22 [/nix/store/06l7idpgs2z417m93zx57bgin9rk4ydh-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 9.0.11 [/nix/store/06l7idpgs2z417m93zx57bgin9rk4ydh-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 6.0.36 [/nix/store/06l7idpgs2z417m93zx57bgin9rk4ydh-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 7.0.20 [/nix/store/06l7idpgs2z417m93zx57bgin9rk4ydh-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 8.0.22 [/nix/store/06l7idpgs2z417m93zx57bgin9rk4ydh-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 9.0.11 [/nix/store/06l7idpgs2z417m93zx57bgin9rk4ydh-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]

Other architectures found:
  None

Environment variables:
  DOTNET_ROOT       [/nix/store/qxrrnqpn18rsgs3nxda3vnlid9jpggdg-dotnet-wrapped-combined/share/dotnet]

global.json file:
  Not found

Learn more:
  https://aka.ms/dotnet/info

Download .NET:
  https://aka.ms/dotnet/download

and with dotnet10 shell:

.NET SDK:
 Version:           10.0.100
 Commit:            b0f34d51fc
 Workload version:  10.0.100-manifests.4c0ca8ba
 MSBuild version:   18.0.2+b0f34d51f

Runtime Environment:
 OS Name:     nixos
 OS Version:  25.11
 OS Platform: Linux
 RID:         linux-x64
 Base Path:   /nix/store/9pa71r5z5sw8z63x1ci4s08b9bj22cz5-dotnet-sdk-10.0.100/share/dotnet/sdk/10.0.100/

.NET workloads installed:
There are no installed workloads to display.
Configured to use workload sets when installing new manifests.
No workload sets are installed. Run "dotnet workload restore" to install a workload set.

Host:
  Version:      10.0.0
  Architecture: x64
  Commit:       b0f34d51fc

.NET SDKs installed:
  10.0.100 [/nix/store/n0ff8bx95icgp6q4a111cpbwdxg6k4yp-dotnet-combined/share/dotnet/sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 6.0.36 [/nix/store/n0ff8bx95icgp6q4a111cpbwdxg6k4yp-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 7.0.20 [/nix/store/n0ff8bx95icgp6q4a111cpbwdxg6k4yp-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 8.0.22 [/nix/store/n0ff8bx95icgp6q4a111cpbwdxg6k4yp-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 9.0.11 [/nix/store/n0ff8bx95icgp6q4a111cpbwdxg6k4yp-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 10.0.0 [/nix/store/n0ff8bx95icgp6q4a111cpbwdxg6k4yp-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 6.0.36 [/nix/store/n0ff8bx95icgp6q4a111cpbwdxg6k4yp-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 7.0.20 [/nix/store/n0ff8bx95icgp6q4a111cpbwdxg6k4yp-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 8.0.22 [/nix/store/n0ff8bx95icgp6q4a111cpbwdxg6k4yp-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 9.0.11 [/nix/store/n0ff8bx95icgp6q4a111cpbwdxg6k4yp-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 10.0.0 [/nix/store/n0ff8bx95icgp6q4a111cpbwdxg6k4yp-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]

Other architectures found:
  None

Environment variables:
  DOTNET_CLI_TELEMETRY_OPTOUT              [1]
  DOTNET_NOLOGO                            [1]
  DOTNET_PATH                              [/nix/store/xyml2j5kssim6iz4lg51fvy10kc90468-dotnet-wrapped-combined/bin/dotnet]
  DOTNET_ROOT                              [/nix/store/xyml2j5kssim6iz4lg51fvy10kc90468-dotnet-wrapped-combined/share/dotnet]
  DOTNET_SKIP_FIRST_TIME_EXPERIENCE        [1]
  DOTNET_SKIP_WORKLOAD_INTEGRITY_CHECK     [1]

global.json file:
  Not found

Learn more:
  https://aka.ms/dotnet/info

Download .NET:
  https://aka.ms/dotnet/download

I have these env vars set:

      DOTNET_PATH = "${combinedNetCorePackages}/bin/dotnet";
      DOTNET_ROOT = "${combinedNetCorePackages}/share/dotnet";

I also tried to make a dev shell with sdk 10 but without runtime / aspnetcore 10, but this still gives me the same problem.

If you want to see my exact setup:

packages:

• https://gitlab.com/gaj-nixos/shared/-/blob/main/pkgs/dotnet/dotnet9.nix?ref_type=heads
• https://gitlab.com/gaj-nixos/shared/-/blob/main/pkgs/dotnet/dotnet10.nix?ref_type=heads

dev shells:

• https://gitlab.com/gaj-nixos/shared/-/blob/main/dev-shells/dotnet9/default.nix?ref_type=heads
• https://gitlab.com/gaj-nixos/shared/-/blob/main/dev-shells/dotnet10/default.nix?ref_type=heads

modules (nixos & home-manager):

• https://gitlab.com/gaj-nixos/shared/-/blob/main/features/software/dotnet/modules.nix?ref_type=heads
• https://gitlab.com/gaj-nixos/shared/-/blob/main/features/software/dotnet/home-manager/modules.nix?ref_type=heads

[Aridor2006]

Edit: What seems to fix it for me everywhere is having a global.json present like this: {"sdk":{"version":"8.0.416","rollForward":"latestFeature"}}

Having the same problem with both dotnet test and dotnet run. Dotnet build works. Before I had only sdk_8_0 and sdk_9_0 and I was able to build and run both net8.0 and net9.0 projects. Adding sdk_10_0 breaks both net8.0 and net9.0 projects, while 10 still works. It seems like the runtime is following the symlink to the 10 installation instead of using the combined one.

I have it configured like this in home manager. Interestingly on x64 linux I can get dotnet test to work by setting the following env variables:

• MSBUILDALWAYSOVERWRITEREADONLYFILES=1
• MSBUILDTERMINALLOGGER=false

However that doesn't work on aarch64 Darwin.

  packages.dotnetSdks = pkgs.buildEnv {
    name = "dotnetSdks";
    paths = [
      (with pkgs.dotnetCorePackages;
        combinePackages [
          sdk_8_0
          sdk_9_0
          sdk_10_0
        ])
    ];
  };

Dotnet Info:

NET SDK:
 Version:           10.0.100
 Commit:            b0f34d51fc
 Workload version:  10.0.100-manifests.4eab3e0f
 MSBuild version:   18.0.2+b0f34d51f

Runtime Environment:
 OS Name:     Mac OS X
 OS Version:  26.1
 OS Platform: Darwin
 RID:         osx-arm64
 Base Path:   /nix/store/yh9k2dkcl4w85mw7fahzq5mjvk0w7kx4-dotnet-sdk-10.0.100/share/dotnet/sdk/10.0.100/

.NET workloads installed:
There are no installed workloads to display.
Configured to use workload sets when installing new manifests.
No workload sets are installed. Run "dotnet workload restore" to install a workload set.

Host:
  Version:      10.0.0
  Architecture: arm64
  Commit:       b0f34d51fc

.NET SDKs installed:
  8.0.416 [/nix/store/l4h8j4fqwrkv9hzp3l70pcsc95bl7jaj-dotnet-combined/share/dotnet/sdk]
  9.0.307 [/nix/store/l4h8j4fqwrkv9hzp3l70pcsc95bl7jaj-dotnet-combined/share/dotnet/sdk]
  10.0.100 [/nix/store/l4h8j4fqwrkv9hzp3l70pcsc95bl7jaj-dotnet-combined/share/dotnet/sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 8.0.22 [/nix/store/l4h8j4fqwrkv9hzp3l70pcsc95bl7jaj-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 9.0.11 [/nix/store/l4h8j4fqwrkv9hzp3l70pcsc95bl7jaj-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 10.0.0 [/nix/store/l4h8j4fqwrkv9hzp3l70pcsc95bl7jaj-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 8.0.22 [/nix/store/l4h8j4fqwrkv9hzp3l70pcsc95bl7jaj-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 9.0.11 [/nix/store/l4h8j4fqwrkv9hzp3l70pcsc95bl7jaj-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 10.0.0 [/nix/store/l4h8j4fqwrkv9hzp3l70pcsc95bl7jaj-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]

Other architectures found:
  None

Environment variables:
  Not set

global.json file:
  Not found

Learn more:
  https://aka.ms/dotnet/info

Download .NET:
  https://aka.ms/dotnet/download

[stewild]

For me, explicitly setting DOTNET_ROOT_X64 resolves this issue.

DOTNET_ROOT_X64="$DOTNET_ROOT"

See related discussion in dotnet/sdk#51693

[gaelj]

In my case, setting DOTNET_ROOT_X64="$DOTNET_ROOT" does seem to help when running some projects.

Unfortunately I have other projects which use swagger CLI and those still crash.

I have the impression the problem is with the value of Base Path (reported in dotnet --info) which does not point to the combined package, but to 10.0.100 files.

dotnet swagger tofile --output Resources/swagger.yml --yaml bin/Debug/net9.0/xxx.Server.dll
You must install or update .NET to run this application.

App: /home/gaj/.nuget/packages/swashbuckle.aspnetcore.cli/9.0.6/tools/net9.0/any/dotnet-swagger.dll
Architecture: x64
Framework: 'Microsoft.NETCore.App', version '9.0.0' (x64)
.NET location: /nix/store/ykg62jcq8m0iwq2538mrjbin2gh094yd-dotnet-sdk-10.0.100/share/dotnet/

The following frameworks were found:
  10.0.0 at [/nix/store/ykg62jcq8m0iwq2538mrjbin2gh094yd-dotnet-sdk-10.0.100/share/dotnet/shared/Microsoft.NETCore.App]

Learn more:
https://aka.ms/dotnet/app-launch-failed

To install missing framework, download:
https://aka.ms/dotnet-core-applaunch?framework=Microsoft.NETCore.App&framework_version=9.0.0&arch=x64&rid=linux-x64&os=nixos.25.11

using a global.json file as described above just makes it crash differently:

dotnet swagger tofile --output Resources/swagger.yml --yaml bin/Debug/net9.0/WebAuthentication.Server.dll
The command could not be loaded, possibly because:
  * You intended to execute a .NET application:
      The application 'swagger' does not exist or is not a managed .dll or .exe.
  * You intended to execute a .NET SDK command:
      A compatible .NET SDK was not found.

Requested SDK version: 8.0.416
global.json file: /srv/gitlab.xxx.xxx/global.json

Installed SDKs:
10.0.100 [/nix/store/4n095nyffqhzc2nl0vbylnzvxnaah3dm-dotnet-combined/share/dotnet/sdk]

Install the [8.0.416] .NET SDK or update [/srv/gitlab.xxx.xxx/global.json] to match an installed SDK.

Learn about SDK resolution:
https://aka.ms/dotnet/sdk-not-found

[corngood]

I'm just working on a test for this

master...corngood:nixpkgs:dotnet-cross-target-test

This is odd:

$ dotnet run
App: /tmp/nix-shell.pfkBU0/test/bin/Debug/net9.0/test
Architecture: x64
Framework: 'Microsoft.NETCore.App', version '9.0.0' (x64)
.NET location: /nix/store/jl3858nslcfn094yhs51hgq7sg6ksv6r-dotnet-sdk-10.0.100/share/dotnet

The following frameworks were found:
  10.0.0 at [/nix/store/jl3858nslcfn094yhs51hgq7sg6ksv6r-dotnet-sdk-10.0.100/share/dotnet/shared/Microsoft.NETCore.App]

Learn more:
https://aka.ms/dotnet/app-launch-failed

To install missing framework, download:
https://aka.ms/dotnet-core-applaunch?framework=Microsoft.NETCore.App&framework_version=9.0.0&arch=x64&rid=linux-x64&os=nixos.25.11

$ dotnet --list-runtimes
Microsoft.AspNetCore.App 9.0.11 [/nix/store/gask04g26i87x10vviflb32la9avgpmn-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 10.0.0 [/nix/store/gask04g26i87x10vviflb32la9avgpmn-dotnet-combined/share/dotnet/shared/Microsoft.AspNetCore.App]
Microsoft.NETCore.App 9.0.11 [/nix/store/gask04g26i87x10vviflb32la9avgpmn-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]
Microsoft.NETCore.App 10.0.0 [/nix/store/gask04g26i87x10vviflb32la9avgpmn-dotnet-combined/share/dotnet/shared/Microsoft.NETCore.App]

I'm guessing it has something to do with combinePackages and the symlinks causing it to find sdk10 rather than the combined package.

[corngood]

It looks like this was introduced with: dotnet/sdk@69ae64b

By using a path relative to the SDK after following the symlinks, it's finding the muxer in dotnet-sdk_10, rather than the one in combinePackages.

[dynnian]

Looks like csharp-ls is broken in nixpkgs 25.11 because of this bug.

You must install or update .NET to run this application.

App: /nix/store/5kjzdkp7jrq132zyxq2r91vbnl42z8bi-csharp-ls-0.20.0/lib/csharp-ls/csharp-ls
Architecture: x64
Framework: 'Microsoft.NETCore.App', version '9.0.0' (x64)
.NET location: /nix/store/jl3858nslcfn094yhs51hgq7sg6ksv6r-dotnet-sdk-10.0.100/share/dotnet

The following frameworks were found:
  10.0.0 at [/nix/store/jl3858nslcfn094yhs51hgq7sg6ksv6r-dotnet-sdk-10.0.100/share/dotnet/shared/Microsoft.NETCore.App]

Learn more:
https://aka.ms/dotnet/app-launch-failed

To install missing framework, download:
https://aka.ms/dotnet-core-applaunch?framework=Microsoft.NETCore.App&framework_version=9.0.0&arch=x64&rid=linux-x64&os=nixos.25.11

Process csharp-ls stderr finished

I only have dotnet 10 installed, I'll install dotnet 9 and see what happens.

[dynnian]

Doing this:

  dotnet = with pkgs.dotnetCorePackages; combinePackages [
    sdk_9_0
    sdk_10_0
    runtime_9_0
    runtime_10_0
    aspnetcore_9_0
    aspnetcore_10_0
  ];
  csharpLsFixed = pkgs.writeShellScriptBin "csharp-ls" ''
    export DOTNET_ROOT="${dotnet}/share/dotnet"
    export DOTNET_ROOT_X64="$DOTNET_ROOT"
    export DOTNET_MULTILEVEL_LOOKUP=0
    exec "${pkgs.csharp-ls}/lib/csharp-ls/csharp-ls" "$@"
  '';

And adding both dotnet and csharpLsFixed to home manager's home.packages fixed csharp-ls for me. Got help from GPT ngl, but works for now.

My home manager module to install dotnet globally

{ pkgs, lib, ... }:
let
  dotnet = with pkgs.dotnetCorePackages; combinePackages [
    # SDKs
    sdk_9_0
    sdk_10_0

    # Runtimes
    runtime_9_0
    runtime_10_0

    # ASP.NET Core runtimes
    aspnetcore_9_0
    aspnetcore_10_0
  ];
  csharpLsFixed = pkgs.writeShellScriptBin "csharp-ls" ''
    export DOTNET_ROOT="${dotnet}/share/dotnet"
    export DOTNET_ROOT_X64="$DOTNET_ROOT"
    export DOTNET_MULTILEVEL_LOOKUP=0
    exec "${pkgs.csharp-ls}/lib/csharp-ls/csharp-ls" "$@"
  '';
in {
  home.packages = with pkgs; [
    dotnet
    dotnetPackages.Nuget
    mono
    csharpier
    csharpLsFixed
    csharprepl
    jetbrains.rider
  ];

  home.sessionVariables = {
    # Helps Rider / tooling that expects DOTNET_ROOT
    DOTNET_ROOT = "${dotnet}/share/dotnet";
    DOTNET_ROOT_X64 = "$DOTNET_ROOT";

    # Recommended on NixOS to avoid “multi-level” probing / weirdness
    DOTNET_MULTILEVEL_LOOKUP = "0";

    # Writable locations (dotnet tends to assume these)
    DOTNET_CLI_HOME = "$HOME/.dotnet";
    NUGET_PACKAGES  = "$HOME/.nuget/packages";

    # Optional niceties
    DOTNET_NOLOGO = "1";
    DOTNET_CLI_TELEMETRY_OPTOUT = "1";
  };

  home.activation.ensureDotnetDirs =
    lib.hm.dag.entryAfter [ "writeBoundary" ] ''
      mkdir -p \
        "$HOME/.dotnet" \
        "$HOME/.nuget/packages" \
        "$HOME/.nuget/NuGet" \
        "$HOME/.local/share/NuGet"
    '';
}

[gaelj]

I can confirm that @dynnian 's workaround solves my problem.

[gaelj]

Well actually, I can build and run, but calling dotnet tools is still broken.

When running a net9.0 dotnet tool on a net9.0 project with the above setup, I get:

swagger:

You must install or update .NET to run this application.

App: /home/gaj/.nuget/packages/swashbuckle.aspnetcore.cli/9.0.6/tools/net9.0/any/dotnet-swagger.dll
Architecture: x64
Framework: 'Microsoft.NETCore.App', version '9.0.0' (x64)
.NET location: /nix/store/ykg62jcq8m0iwq2538mrjbin2gh094yd-dotnet-sdk-10.0.100/share/dotnet/

The following frameworks were found:
  10.0.0 at [/nix/store/ykg62jcq8m0iwq2538mrjbin2gh094yd-dotnet-sdk-10.0.100/share/dotnet/shared/Microsoft.NETCore.App]

dotnet-ef:

You must install or update .NET to run this application.

App: /home/gaj/.nuget/packages/dotnet-ef/9.0.11/tools/net8.0/any/tools/netcoreapp2.0/any/ef.dll
Architecture: x64
Framework: 'Microsoft.NETCore.App', version '9.0.0' (x64)
.NET location: /nix/store/ykg62jcq8m0iwq2538mrjbin2gh094yd-dotnet-sdk-10.0.100/share/dotnet/

The following frameworks were found:
  10.0.0 at [/nix/store/ykg62jcq8m0iwq2538mrjbin2gh094yd-dotnet-sdk-10.0.100/share/dotnet/shared/Microsoft.NETCore.App]