Building n8n Custom Nodes: From Code to Production

Node Architecture: The TypeScript Advantage

Every n8n custom node is a TypeScript class. The SDK gives you type-safe credential management, input validation, and error handling out of the box.

import {
	IExecuteFunctions,
	INodeExecutionData,
	INodeType,
	INodeTypeDescription,
} from 'n8n-workflow';

export class MyCustomNode implements INodeType {
	description: INodeTypeDescription = {
		displayName: 'My Custom Node',
		name: 'myCustomNode',
		group: ['transform'],
		version: 1,
		description: 'Does something useful',
		inputs: ['main'],
		outputs: ['main'],
	};

	async execute(this: IExecuteFunctions): Promise<INodeExecutionData[][]> {
		const items = this.getInputData();
		const results = [];
		
		for (const item of items) {
			results.push(item);
		}
		return [results];
	}
}

The SDK handles credential encryption, maintains isolation between nodes, and manages state. You focus on the integration logic, not infrastructure.