Privilege error when building

[ghost]

When I run pub run build_runner build --output=build, I get the following output:

[INFO] Generating build script completed, took 252ms
[WARNING] Throwing away cached asset graph due to Dart SDK update.
[INFO] Cleaning up outputs from previous builds. completed, took 32ms
[INFO] Generating build script completed, took 64ms
[INFO] Creating build script snapshot... completed, took 7.0s
[INFO] Building new asset graph completed, took 722ms
[INFO] Checking for unexpected pre-existing outputs. completed, took 1ms
[INFO] build_node_compilers:entrypoint on node/index.dart:Running dart2js with --minify --packages=.package-331d3db0d4c542b2c2c29095d74263e9 -onode/index.dart.js node/index.dart
[INFO] build_node_compilers:entrypoint on node/index.dart:Dart2Js finished with:

Compiled 7,908,073 characters Dart to 85,934 characters JavaScript in 2.15 seconds
Dart file node\index.dart compiled to JavaScript: node/index.dart.js

[INFO] Running build completed, took 3.0s
[INFO] Caching finalized dependency graph completed, took 85ms
[INFO] Creating merged output dir `build`...

You have hit a bug in build_runner
Please file an issue with reproduction steps at https://github.com/dart-lang/build/issues

FileSystemException: Cannot create link, path = 'build\node\packages' (OS Error: A required privilege is not held by the client.
, errno = 1314)
dart:io                                                                       _Link.createSync
package:build_runner_core/src/environment/create_merged_dir.dart 93:16        _createMergedOutputDir.<fn>
package:build_runner_core/src/logging/logging.dart 25:30                      logTimedAsync
package:build_runner_core/src/environment/create_merged_dir.dart 72:9         _createMergedOutputDir
package:build_runner_core/src/environment/create_merged_dir.dart 44:16        createMergedOutputDirectories
package:build_runner_core/src/environment/io_environment.dart 81:18           IOEnvironment.finalizeBuild
package:build_runner_core/src/environment/overridable_environment.dart 52:49  OverrideableEnvironment.finalizeBuild
package:build_runner_core/src/generate/build_impl.dart 218:33                 _SingleBuild.run
package:build_runner_core/src/generate/build_impl.dart 93:42                  BuildImpl.run
package:build_runner_core/src/generate/build_runner.dart 24:14                BuildRunner.run
package:build_runner/src/generate/build.dart 111:30                           build
package:build_runner/src/entrypoint/build.dart 28:24                          BuildCommand.run
package:args/command_runner.dart 197:27                                       CommandRunner.runCommand
package:args/command_runner.dart 112:25                                       CommandRunner.run.<fn>
dart:async                                                                    new Future.sync
package:args/command_runner.dart 112:14                                       CommandRunner.run
package:build_runner/src/entrypoint/run.dart 23:31                            run
.dart_tool\build\entrypoint\build.dart 78:22                                  main

I'm using the exact pubspec.yaml, node/index.dart and build.yaml as shown in the readme.

The command works when I run it in a terminal with admin permissions.

Dart VM version: 2.4.0