runtime

Runtime management types.

These dataclasses are returned by runtime/status helper functions and are used internally to decide whether a "prebuilt runtime" can be used on the current machine.

Conceptually:

• A runtime is a bundle containing CmdStan and a set of R packages installed into an isolated library directory (typically under ~/.brmspy/runtime/...).
• An environment (see EnvironmentConfig) is a named, user-managed library (~/.brmspy/environment/<name>/Rlib) layered on top of a runtime.

Notes

All snapshot types in this module are immutable (frozen=True) so they can be cached safely and won't be mutated accidentally by callers.

Classes

SystemInfo dataclass

Immutable snapshot of the system environment relevant to runtime selection.

Attributes:

Name	Type	Description
os	str	Operating system identifier (for example "linux", "macos", "windows").
arch	str	CPU architecture (for example "x86_64", "arm64").
r_version	tuple[int, int, int] or None	Detected R version as (major, minor, patch).
fingerprint	str	Fingerprint used for runtime lookup and caching (for example "linux-x86_64-r4.3").
glibc_version	tuple[int, int] or None	Linux-only: glibc major/minor version used for compatibility checks.
clang_version	tuple[int, int] or None	macOS-only: clang major/minor version.
gxx_version	tuple[int, int] or None	C++ compiler major/minor version if detected.
has_rtools	bool	Windows-only: whether Rtools is available.

RuntimeManifest dataclass

Manifest for a prebuilt runtime bundle.

This structure is typically loaded from a manifest.json stored alongside a runtime directory.

Attributes:

Name	Type	Description
runtime_version	str	brmspy runtime bundle version.
fingerprint	str	System fingerprint this runtime was built for.
r_version	str	R version string used for the runtime build (for example "4.5.0").
cmdstan_version	str	CmdStan version included in the runtime.
r_packages	dict[str, str]	Mapping of R package names to versions.
manifest_hash	str	Hash used to validate the runtime contents.
built_at	str	Build timestamp.

RuntimeStatus dataclass

Immutable snapshot of current runtime state.

Attributes:

Name	Type	Description
active_runtime	Path or None	Path to the currently selected runtime (if any).
is_activated	bool	Whether the worker's embedded R session has been modified/activated to use the active runtime.
system	SystemInfo	Detected system info used for compatibility evaluation.
can_use_prebuilt	bool	Whether a prebuilt runtime could be used in principle.
prebuilt_available	bool	Whether a compatible prebuilt runtime is available for the current fingerprint.
compatibility_issues	tuple[str, ...]	Human-readable reasons why prebuilt runtime usage is not possible.
installed_runtimes	tuple[Path, ...]	Runtime directories currently installed under brmspy storage.
brms_version, cmdstanr_version, rstan_version	str or None	Detected versions in the current worker session (if available).

StoredEnv dataclass

Captured R environment used for deactivation/restoration.

Attributes:

Name	Type	Description
lib_paths	list[str]	.libPaths() values captured before activation.
cmdstan_path	str or None	CmdStan path captured before activation.