Lokad.Bash

An embeddable, non-interactive Bash interpreter for .NET 10 and .NET 11. Your application controls commands, filesystem queries, files, pipes and resource admission through IBashHost. The runtime has no third-party runtime dependencies and does not supply a filesystem or process host.

This checkout prepares version 0.2.0, including the public API migrations in the changelog. Build the package locally and point your consumer's NuGet source to the resulting artifacts/nuget/ directory; publication is separate.

dotnet add package Lokad.Bash --version 0.2.0 --source ./artifacts/nuget

using Lokad.Bash;
using Lokad.Bash.Evaluation;

IBashHost host = new ApplicationBashHost(); // Application-owned capabilities.
using var cancellation = new CancellationTokenSource(TimeSpan.FromSeconds(10));
var result = await BashScript.RunAsync(
    host, "for name in alpha beta; do printf '%s\n' \"$name\"; done",
    EvaluationOptions.Default, cancellation.Token);
Console.WriteLine(result.ExitCode);

ApplicationBashHost is application code. The test suite's small host and filesystem fixture illustrate the contract. They are test fixtures and are not included in the package.

For syntax inspection, use Syntax.Parser.TryParse or Helpers.ShellCommandParser.TryParseChain. For prepared or stepped execution, construct Evaluation.Evaluation and drive it through Engine. Keep retained source bytes immutable and retain their storage through all users.

This is a Bash subset. It deliberately excludes interactive sessions, job control, OS signals, startup files and ambient machine access. Shell utilities are supplied by the host. See compatibility, runtime contracts and memory design for exact boundaries. Cancellation and memory admission are cooperative; this library is not an OS isolation boundary.

Build

Install the SDK in global.json and the .NET 10 runtime. The pinned .NET 11 SDK is a release candidate; both target frameworks are built and tested explicitly.

dotnet restore Lokad.Bash.slnx --locked-mode
dotnet test Lokad.Bash.slnx -c Release --no-restore
dotnet pack src/Lokad.Bash/Lokad.Bash.csproj -c Release --no-restore
./scripts/Test-NuGetPackage.ps1 -PackagePath artifacts/nuget/Lokad.Bash.0.2.0.nupkg

Language and evaluator-contract regressions use in-memory IBashHost fixtures. Their small command stubs support language assertions; utility implementations, storage systems and application command-adapter policies are tested by their hosts. See test ownership for boundary responsibilities and qualification.

CI runs on Windows and Linux. Packages go to artifacts/nuget/ as Lokad.Bash.0.2.0.nupkg and Lokad.Bash.0.2.0.snupkg. The installed consumer restores only from the produced package in an isolated feed/cache, checks assembly hashes and exercises both runtimes through the public API. CI retains its evidence. Before 1.0, minor versions may change public APIs, with migration notes in the changelog.

The benchmarks use separate non-packable driver/probe projects. Preparation, equivalence checks, lifecycle previews, core checks and isolated allocation/native RSS smoke modes run without comparative timings. The dedicated-VM campaign is complete: 1,254 timing rows, 846 separate cold memory observations and explicit startup controls cover 25 macro families and 12 core kernels on both runtimes. The report retains each family's boundaries, scaling, limitations and subsequent investigation priorities.

GNU correctness controls

The versioned corpus in tests/Lokad.Bash.Tests/Conformance/cases.json has explicit byte/status expectations, script hashes and pinned GNU reference versions/hashes. The ordinary test suite checks supported cases and separately declared managed expectations for known deviations. The native verifier checks every applicable case's GNU expectation, retaining each deviation's reason. Run it with PowerShell 7:

./scripts/Verify-GnuBash.ps1 -ReferencePath /usr/bin/bash
# Windows with the pinned Ubuntu/WSL reference:
./scripts/Verify-GnuBash.ps1 -ReferencePath /usr/bin/bash -WslDistribution Ubuntu

The verifier rejects an unexpected reference binary and writes results under artifacts/conformance/. These are correctness controls, not a conformance score or performance measurements. The MSYS reference covers byte/C-locale controls; Linux C.utf8 is the character-semantics reference. Broader compatibility gaps remain documented in compatibility.