Configuration playground for domain experts

Context

Loan assessment logic changes often start with analysts who understand credit policy but cannot safely experiment in production. Testing a policy change often required an engineer to run a script or interpret spreadsheet changes before analysts could compare the result.

Constraints

• No customer or production data in the playground; synthetic inputs only.
• Changes must be explainable to compliance-minded reviewers, not only to the author.
• The tool should complement — not replace — the authoritative servicing systems.

Approach

1. Keep policy exploration separate from execution — give analysts configurable scenarios with named inputs and expected outputs they could compare.
2. Define what could change — show which parameters were editable, which were fixed, and which needed an engineering release.
3. Save useful scenarios — use them as regression cases when a policy changed again next quarter.

Trade-offs

The playground was not a full staging clone, so some integration behavior stayed mocked. That limit let analysts test policy questions quickly without reproducing the entire core-banking environment.

Outcomes

• Analysts iterate on assessment questions without queueing engineering for every variant.
• When a change needed engineering work, the request already had clearer inputs and expected outputs.