Move business rules out of application code

Rules that change every month live in application code. Decisimo automates finance decisions through rule sets and decision tables that owners can read and change.

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What a rule looks like in Decisimo

A rule set is an ordered list of if-then rules. Each rule meets all or any of its conditions, with groups that nest inside one another. It reads inputs and earlier results in the decision flow by path in one JSON document, then sets values and calculates results. Array rules run over each item in a list.

Application fraud rule set showing conditions and actions for an unavailable IP provider and multiple confirmed-fraud details
This screen shows the Application fraud rules rule set, with conditions and actions for a fraud decision. Its conditions and actions show rule owners what the logic reads and changes before they revise the rule set.

Decision tables for logic that is a matrix

A decision table uses condition columns and result columns. Cells can hold ANY, comparisons or open and closed ranges, and the last matching row wins unless the table uses first-match mode. The table checks overlapping rows and imports or exports CSV; read the practical guide to decision tables.

Score Cutoff decision table with Knocked out and Score conditions mapped to decline, refer, and approve results
This screen shows the Score Cutoff decision table with condition and result columns. Its rows keep conditions and results together when the policy is revised.

One decision flow, one endpoint

A decision flow joins rule sets, decision tables, decision trees, scorecards, functions, data sources and models. If a data source call fails, its output becomes a value that a rule can read. The application sends one JSON document to the flow's endpoint and receives the whole document back. Connect a provider to add external data.

Consumer Lending Decision flow connects Affordability, Knock-out rules, Risk Scorecard and Score Cutoff between Start and End
This screen shows the Consumer Lending Decision flow, joining a function, rule set, scorecard and decision table. Rule owners can inspect how these components combine before the flow runs through its endpoint.

Changing a rule, testing it, releasing it

Editing creates a revision that you can compare with an earlier revision or revert. Each decision artifact has its own tests, and saved cases rerun as regression tests. The impact analyzer shows which past decisions would change, and nothing runs until a release is deployed. See running decisions through the endpoint and testing each release.

Questions we get asked

What is a business rules engine?

It is software that applies business rules to a decision outside application code. Decisimo runs rule sets, decision tables, decision trees, scorecards and functions in a decision flow.

Does changing a rule need a developer?

Changing a rule does not involve changing application code. The portal has precise fields for JSON paths, formula syntax and regular expressions, so the person editing needs to understand those parts.

Can rules use data from external APIs?

Yes. A data source can call a REST or SOAP API that returns JSON or XML. If the call fails, a rule can read the error and HTTP code in its output.

Can rules use machine learning models?

A decision flow can call a model over HTTP, run an uploaded Python, R or Julia model, or use an LLM. The model's output can be read by later decision logic.

How is a rule change tested before it runs?

Saved cases rerun as regression tests, and a release can run over a file of cases. The impact analyzer compares the current release with a changed one over past decisions and shows which decisions would change.

See how your rules would run

Book a demo to see how your rules can run through one endpoint.

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