Domain model and workflow boundaries

fincore works with labelled pandas inputs. Most direct metric functions accept a return Series; portfolio and reporting workflows optionally accept aligned positions, transactions, benchmarks, and metadata.

One operation, one owner

The public API is deliberately not a flat convenience layer. A function lives in the domain responsible for its semantics:

from fincore.metrics.ratios import sharpe_ratio
from fincore.performance.cashflows import cashflow_adjusted_twr
from fincore.report.portfolio.compute import build_portfolio_report

This keeps validation, numerical behaviour, and optional dependencies local to the operation rather than routing calls through package-shaped compatibility layers.

Immutable boundaries

Canonical report documents, runtime artifacts, data snapshots, and extension snapshots are immutable at their public boundary. Callers can retain a result without later calculations silently changing it.

Optional capabilities

Core analysis does not import renderers, providers, Bayesian engines, or interactive backends eagerly. Install the named extra for the capability you select, such as fincore[visualization] or fincore[report-xlsx].

Removed 0.5 surfaces

Upstream-shaped module paths, root-level calls, stateful analysis context objects, and rolling-engine facades were removed. See the migration guide for the purpose-based replacement map.