Buck2

Buck2 has a native Remote Execution API client. NativeLink can serve the CAS, Action Cache, capabilities, and execution services that Buck2 expects.

The repo includes a runnable Buck2 integration test at integration_tests/buck2/. It starts NativeLink with a combined scheduler and local worker, runs buck2 build //..., and checks for BUILD SUCCEEDED.

Start NativeLink

Use a config that exposes these services on localhost:50051:

• CAS
• Action Cache
• execution
• capabilities
• ByteStream

The integration test uses integration_tests/buck2/buck2_cas.json5 and instance name main.

Configure Buck2

In your Buck2 project, add .buckconfig:

[cells]
root = .

[buck2_re_client]
engine_address = localhost:50051
action_cache_address = localhost:50051
cas_address = localhost:50051
tls = false
instance_name = main

[build]
execution_platforms = root//platforms:platforms

The checked-in integration test uses the same settings in integration_tests/buck2/.buckconfig.

Register an execution platform

Buck2 needs an execution platform that allows remote actions. The integration test registers one with remote_enabled = true and local_enabled = true:

platform = ExecutionPlatformInfo(
    label = ctx.label.raw_target(),
    configuration = configuration,
    executor_config = CommandExecutorConfig(
        local_enabled = True,
        remote_enabled = True,
        use_limited_hybrid = True,
        remote_execution_properties = {},
        remote_execution_use_case = "buck2-default",
        remote_output_paths = "output_paths",
    ),
)

See integration_tests/buck2/platforms/defs.bzl for the complete rule.

Run a build

buck2 build //...

The integration test uses a small staged build graph that mixes local-only and remote-capable actions, then verifies the output with diff. That shape is useful when validating a new cluster because it proves both upload and download paths are working.

Troubleshooting

• Buck2 cannot connect. Confirm NativeLink is listening on 50051 and Buck2 is not expecting TLS.
• Everything runs locally. Check that your selected execution platform sets remote_enabled = True.
• Instance-name errors. Make sure Buck2's instance_name matches the NativeLink config. The integration test uses main.