Make every first-party SDK runnable from a fresh Codespace

[rmcdaniel]

A fresh Sample App Codespace is not yet a truthful playground for all first-party SDKs. PHP embedded examples are immediately available, while framework-neutral PHP, Python, and Rust authoring are hidden behind containerized onboarding or the conformance matrix. The default environment lacks Python and Rust authoring toolchains, Docker Compose access, and the Durable Workflow CLI. An evaluator can read the SDK references and ask an agent to create a workflow and activity from scratch, yet the agent cannot execute a valid path from inside the repository.

Make Sample App an easy, symmetric PHP, Python, and Rust playground without regressing Codespaces startup performance.

Acceptance criteria

• After a fresh Codespace reports setup complete, PHP and Composer, Python 3.10 or newer with isolated package support, Rust 1.86 or newer with Cargo, Docker Compose, and dw are directly executable by the non-root Codespaces user.
• Tooling is supplied by the published development image or a bounded checksum-verified cache/bootstrap. The post-create path does not run apt, rustup, compile the CLI, or rebuild language toolchains.
• Docker access works from inside the development container and is permission-safe for the non-root user; every documented service-mode command passes its Docker preflight in Codespaces.
• Expose one memorable playground interface with symmetric php, python, and rust choices. Each choice can scaffold or run caller-owned source against an isolated published Server and prints the completed result plus the exact Waterline run URL.
• Each proof creates new workflow and activity source outside the repository's canonical matrix workers, registers a worker, starts the workflow, executes the activity, and receives the result. Replaying a prewritten conformance cell is insufficient.
• The PHP path covers the framework-neutral SDK with an ergonomic Laravel integration option; moving from embedded Laravel to service mode must not discard dependency injection, configuration, logging, or testability.
• Python and Rust dependencies for the supported SDK floors are pre-fetched or otherwise cached so first use is not dominated by rebuilding the SDK dependency graph.
• The top-level README and repository agent guidance make the three paths discoverable from a natural-language request to create and run a workflow. Users do not need to infer conformance commands.
• CI runs the same authored-from-scratch journey for PHP, Python, and Rust using published artifacts and verifies each result, worker registration, workflow history, and Waterline selection.
• A fresh standard two-core Codespace records creation timing and executes all three journeys as the normal user. Setup remains under five minutes, the repository stays clean except for intentionally created playground source, and no recovery container or manual package installation is used.

Close only after exact fresh-Codespace transcripts and timing evidence for all three SDKs are attached.

[rmcdaniel]

Fresh Codespace evidence on 2026-08-11 confirms partial progress: Rust, Cargo, and dw were directly available and the evaluator did not install or scaffold a toolchain. A Rust workflow plus activity completed against a managed namespace.

This does not satisfy the playground contract yet. The evaluator had to modify and build the comprehensive conformance worker, the checked-in worker used Rust SDK 2.0.0-rc.5, and workflow start fell back from the CLI to raw HTTP. Keep this open until the same obvious authored-from-scratch interface works symmetrically for PHP, Python, and Rust using current artifacts and prints the managed run location.

[rmcdaniel]

Partial fresh-environment evidence (2026-08-11): the evaluator reports Rust, Cargo, and dw were directly available and cargo test plus a release build succeeded without installing tooling. That confirms the missing-toolchain defect has improved. The run modified the existing comprehensive conformance worker, used its helpers and registration pattern, and did not exercise the symmetric PHP/Python playground or record fresh Codespace creation timing. It therefore does not satisfy the authored-from-scratch or all-SDK acceptance criteria. Preserve the working preinstalled toolchain while completing the memorable caller-owned playground path.

[rmcdaniel]

Consolidated into #41; the full acceptance criteria are retained in that root issue.