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Visual tour

From APIs to the numerical core

Python and Rust entry points share the portfolio layer and ledge-core kernel

Python and Rust callers use the same portfolio semantics. The portfolio layer compiles budget, boxes, exposure templates, turnover, and tracking error into the factor-structured kernel. ledge-core performs scaling, ADMM/SMW updates, the exact L1 proximal step, polishing, and independent audits without forming the dense covariance matrix.

One model, many rebalance dates

A rolling sequence updates data while reusing structure and warm starts

A PortfolioSequence holds fixed covariance and constraint structure. Each date updates expected returns and holdings, then reuses cached reduced factorizations and the preceding primal/dual solution. The annotation comes from the repository's seeded 300-asset, 24-date example; run python docs/examples/rolling_backtest.py to reproduce it.

Measured comparison, not a marketing sketch

Published L1 rolling comparison on a logarithmic milliseconds-per-step scale

The bars are parsed directly from the committed benchmarks/results/2026-07-l1/summary.md: ten repeats with ten rolling steps per repeat. Ledge uses its native L1 proximal block; OSQP and Clarabel receive factor-lifted epigraph formulations. The chart is deliberately logarithmic because the range spans four orders of magnitude.

The full report includes setup, cold, rolling, status, iteration, and independently audited residual data. Read the benchmark evidence chapter before quoting a result.

Reproduce the visuals

From the repository root:

python scripts/generate_demo_assets.py --check
python scripts/generate_demo_assets.py

The script uses the standard library for SVGs and Pillow for the README's terminal GIF. Provenance and refresh instructions live in docs/assets/README.md.