Neuron-JS vs node-rules

node-rules is an older Node.js business rules engine with durable category awareness. Keep it when the existing system works and migration would add risk without operational benefit. Choose Neuron-JS when the next version of the rules layer must be serializable, TypeScript-owned, validation-first, and explainable.

Fast answer

Use Neuron-JS when business rules need to become governed JSON assets in a modern TypeScript codebase.

Use node-rules when maintaining an existing Node.js rules system is simpler, safer, and already satisfies the product requirements.

Decision matrix

Need	Neuron-JS	node-rules
Modern TypeScript package surface	Yes	Limited/older style
Serializable JSON rule assets	Yes	Partial/project-specific
Registry-owned vocabulary	Yes	Project-owned rule functions
Validation before runtime	Built in	Project-owned
Explanation traces	Built in	Project-owned
Existing Node rules maintenance	Migration required	Strong fit if already adopted
Best fit	New or modernized TypeScript rule systems	Existing older Node.js rules systems

Choose Neuron-JS when

Rules need to be stored, versioned, reviewed, or edited outside deployment cycles.
A TypeScript team wants explicit extension classes and package-root imports.
Generated rules need validation before execution.
The product needs explanation traces for audit, support, or regression tests.
Workflow automation needs deterministic decisions from approved JSON input.

Choose node-rules when

The current node-rules implementation is stable and well tested.
The rule layer depends on behavior that would be expensive to recreate.
The team does not need JSON schema validation, AI-generated rule safety, or explanation traces.
Migration would create more risk than keeping the older engine.

Migration guide

Treat migration as a model cleanup. Convert implicit rule-function behavior into explicit data contracts and approved registry components.

Before: imperative Node.js rule style

typescript

const rule = {
  condition(R) {
    R.when(this.cartTotal >= 100 && this.customerTier === 'gold');
  },
  consequence(R) {
    this.discountPercent = 15;
    R.stop();
  },
};

After: Neuron-JS script

json

{
  "id": "gold-tier-pricing-policy",
  "rules": [
    {
      "id": "gold-cart-discount",
      "type": "simple_rule",
      "options": {},
      "conditions": [
        {
          "id": "cart-threshold",
          "type": "compare_two_numbers",
          "options": {},
          "params": [
            { "id": "cart-total", "name": "op1", "type": "simple_number", "value": "125", "options": {} },
            { "id": "operator", "name": "comp", "type": "comparator", "value": ">=", "options": {} },
            { "id": "minimum", "name": "op2", "type": "simple_number", "value": "100", "options": {} }
          ]
        }
      ],
      "actions": [
        {
          "id": "discount-value",
          "type": "add_two_numbers",
          "options": {},
          "params": [
            { "id": "base-discount", "name": "op1", "type": "simple_number", "value": "10", "options": {} },
            { "id": "gold-bonus", "name": "op2", "type": "simple_number", "value": "5", "options": {} }
          ]
        }
      ]
    }
  ]
}

Validate and explain the migrated rule

typescript

import {
  Neuron,
  Synapse,
  explainExecution,
  summarizeExecutionOutput,
  validateExecutionContext,
  validateScript,
} from '@sebasoft/neuron-js';

const context = { messages: [], state: { cartTotal: 125, customerTier: 'gold' } };

const scriptValidation = validateScript(script);
const contextValidation = validateExecutionContext(context);

if (!scriptValidation.ok || !contextValidation.ok) {
  throw new Error('Invalid migrated rule input');
}

const result = new Synapse(new Neuron()).execute(script, context);
const output = summarizeExecutionOutput(result);
const explanation = explainExecution({ script, result });

Migration checklist

Inventory existing rules and rank by business value and risk.
Preserve current behavior with characterization tests before translating rules.
Move rule conditions into approved Neuron-JS condition types.
Move consequences into approved Neuron-JS action types.
Make stop/priority behavior explicit in tests; do not assume execution order equivalence.
Validate with validateScript(script).
Add explanation snapshots for the highest-risk rules.

Neuron-JS vs node-rules ​

Fast answer ​

Decision matrix ​

Choose Neuron-JS when ​

Choose node-rules when ​

Migration guide ​

Before: imperative Node.js rule style ​

After: Neuron-JS script ​

Validate and explain the migrated rule ​

Migration checklist ​

Related docs ​