Open Arsenal

A transparent engine for controlled amortization.

Solvra is an open-source financial modeling engine built to bring structure, transparency, and predictability to loan amortization. It replaces traditional compounding-driven mortgage behavior with a controlled system where interest is calculated under a defined cap and distributed uniformly across the full loan term. This creates a deterministic framework for understanding how loans behave across different durations without hidden variability in payment structure.

At its core, Solvra uses a capped-interest model based on a maximum 15-year effective interest window. This means that even if a loan extends beyond 15 years, the total interest exposure does not increase beyond that limit. Instead, the system ensures that the total interest is calculated within this constraint and then spread evenly across every payment period in the loan, producing consistent monthly payments regardless of term length.

Solvra’s feature set is centered around scenario modeling and financial transparency. Users can compare multiple loan terms side-by-side, analyze how different interest rates impact affordability, and test long-term financial outcomes under consistent rules. Because every calculation is deterministic, results are fully reproducible and ideal for structured planning, stress testing, and comparative analysis.

By removing traditional amortization irregularities and enforcing a uniform distribution model, Solvra provides a simplified yet powerful way to evaluate debt structures. It is designed for clarity-focused financial analysis rather than market-based lending simulation, making it particularly useful for modeling controlled lending environments, regulatory scenarios, and predictable payment planning systems.

This specification is released under the GNU Affero General Public License v3.0 or later (AGPL-3.0+) and may be used freely with required attribution under Section 7. A Specification Branding License is available for attribution-free deployments, with fees based on usage, scope, and deployment size.