diff --git a/src/utils/errors.js b/src/utils/errors.js
new file mode 100644
index 0000000..3f42ec5
--- /dev/null
+++ b/src/utils/errors.js
@@ -0,0 +1,50 @@
+const errorHandler = (err, environment) => {
+	// no stacktraces leaked to user
+	const responseJson = {}
+	console.error(err)
+	switch (err.code) {
+		case 'ER_DUP_ENTRY':
+			responseJson.message = 'Conflict'
+			responseJson.code = 409
+			break
+		case 'BAD_REQUEST':
+			responseJson.message = 'Bad Request'
+			responseJson.code = 400
+			break
+		case 'NOT_FOUND':
+			responseJson.message = 'Not Found'
+			responseJson.code = 404
+			break
+		case 'UNPROCESSABLE_ENTITY':
+			responseJson.message = 'Unprocessable Entity'
+			responseJson.code = 422
+			break
+		default:
+			responseJson.message = 'Server Error'
+			responseJson.code = 500
+			break
+	}
+
+	// development error handler
+	// will print stacktrace
+	if (environment === 'development' || environment === 'test') {
+		responseJson.error = err
+	}
+	return responseJson
+}
+
+const error404 = () => {
+	const err = new Error('Not Found')
+	err.code = 'NOT_FOUND'
+	err.status = 404
+	return err
+}
+
+const error422 = (message = 'Unprocessable Entity') => {
+	const err = new Error(message)
+	err.code = 'UNPROCESSABLE_ENTITY'
+	err.status = 422
+	return err
+}
+
+export { error404, error422, errorHandler }
diff --git a/src/utils/hasChildren.js b/src/utils/hasChildren.js
new file mode 100644
index 0000000..ecdb8f8
--- /dev/null
+++ b/src/utils/hasChildren.js
@@ -0,0 +1,21 @@
+import { hasChildrenModel } from '../models/hasChildrenModel'
+
+const hasChildren = (req, res, next, config, { adapter, schema, table1, fieldNameTable1, uuidTable1, table2, fieldNameTable2 }) => {
+	return new Promise((resolve) => {
+		const conn = adapter.start(config)
+		resolve(hasChildrenModel({ adapter, schema, table1, fieldNameTable1, uuidTable1, table2, fieldNameTable2 }, conn)
+			.then((hasChildren) => {
+				const result = hasChildren === undefined || hasChildren.length === 0 ? [] : { hasChildren }
+				next(result)
+				return result
+			})
+			.catch((err) => {
+				throw (err.message)
+			})
+			.finally(() => {
+				adapter.end(conn)
+			}))
+	})
+}
+
+export { hasChildren }
diff --git a/src/utils/hasChildrenValidator.js b/src/utils/hasChildrenValidator.js
new file mode 100644
index 0000000..d42d3f6
--- /dev/null
+++ b/src/utils/hasChildrenValidator.js
@@ -0,0 +1,8 @@
+import { sendUnprocessableEntityResponse } from './responses'
+
+const hasChildrenValidator = (result, req, res, next, config) => {
+	return result.length === 0
+		? next(result)
+		: sendUnprocessableEntityResponse(res, config.environment)
+}
+export { hasChildrenValidator }
diff --git a/src/utils/links.js b/src/utils/links.js
new file mode 100644
index 0000000..673965d
--- /dev/null
+++ b/src/utils/links.js
@@ -0,0 +1,23 @@
+const addLinks = (result, req, res, next, hasAddLinks, routes) => {
+	const links = { _links: routes }
+
+	hasAddLinks ? next(Object.assign({}, links, result)) : next(result, req, res, next, routes)
+}
+
+const getRoutes = ({ prefix, routes }) => routes
+	.filter(r => r.route)
+	.reduce((acc, route) => {
+		const capitalize = val => val.charAt(0).toUpperCase() + val.slice(1)
+		const entity = route.route.path
+			.split('/')
+			.map(val => val.replace(':', ''))
+			.map(val => val.replace('-', ''))
+			.map(capitalize)
+			.join('')
+
+		const method = Object.keys(route.route.methods)[0]
+		const newEndpoint = { [method + entity]: `${method.toUpperCase()} - ${prefix}${route.route.path}` }
+		return { ...acc, ...newEndpoint }
+	}, {})
+
+export { addLinks, getRoutes }
diff --git a/src/utils/pagination.js b/src/utils/pagination.js
new file mode 100644
index 0000000..dd039dc
--- /dev/null
+++ b/src/utils/pagination.js
@@ -0,0 +1,12 @@
+const pagination = ({ limit, page }) => {
+	const validateLimit = Number.isNaN(Number(limit)) || limit === '' ? 100 : Math.abs(limit)
+	const validatePage = Number.isNaN(Number(page)) || page === '' ? 1 : Math.abs(page)
+
+	const auxPage = Number.parseInt(validatePage) === 0 ? 1 : Number.parseInt(validatePage)
+	const auxLimit = Math.abs(Number.parseInt(validateLimit))
+
+	const offset = (Math.abs(auxPage) - 1) * auxLimit
+	return ` LIMIT ${auxLimit} OFFSET ${offset} `
+}
+
+export { pagination }
diff --git a/src/utils/responses.js b/src/utils/responses.js
new file mode 100644
index 0000000..f9787ed
--- /dev/null
+++ b/src/utils/responses.js
@@ -0,0 +1,48 @@
+import { error422, errorHandler } from './errors.js'
+
+const sendOkResponse = (result, req, res) => {
+	res.status(200).json(result)
+}
+const sendCreatedResponse = (result, req, res) => {
+	res.status(201).json(result)
+}
+
+const sendResponseNoContent = (result, req, res) => {
+	res.status(204).json(result)
+}
+
+const sendResponseServerError = (res, err) => {
+	res.status(500).json(err)
+}
+
+const sendResponseBadRequest = (res, err) => {
+	res.status(400).json(err)
+}
+
+const sendResponseUnauthorized = (res, err) => {
+	return res.status(401).json(err)
+}
+
+const sendResponseAccessDenied = (res, err) => {
+	return res.status(403).json(err)
+}
+
+const sendResponseNotFound = (res, err) => {
+	res.status(404).json(err)
+}
+
+const sendResponseUnprocessableEntity = (res, err) => {
+	res.status(422).json(err)
+}
+
+const sendUnprocessableEntityResponse = (res, environment, err = error422()) => {
+	const error = errorHandler(err, environment)
+	res.status(422).json(error)
+}
+
+const sendLoginSuccessfullResponse = (result, req, res) => {
+	res.status(201).json(result)
+	console.warn(`User ${result.user._data.username} has logged in`)
+}
+
+export { sendLoginSuccessfullResponse, sendCreatedResponse, sendResponseAccessDenied, sendOkResponse, sendResponseBadRequest, sendResponseNoContent, sendResponseNotFound, sendResponseServerError, sendResponseUnauthorized, sendResponseUnprocessableEntity, sendUnprocessableEntityResponse }