diff --git a/lib/validator.js b/lib/validator.js
index b281ff2..73d8696 100644
--- a/lib/validator.js
+++ b/lib/validator.js
@@ -235,8 +235,9 @@ class Validator {
 				res.source = res.source.replace(/%%INDEX%%/g, rule.index);
 				const fn = new Function("value", "field", "parent", "errors", "context", res.source);
 				context.fn[rule.index] = fn;
-				sourceCode.push(this.makeCustomValidator({vName: resVar, path: customPath, schema: rule.schema, context, messages: rule.messages, ruleIndex: rule.index}));
 				sourceCode.push(this.wrapRequiredCheckSourceCode(rule, innerSrc.replace(/%%INDEX%%/g, rule.index), resVar));
+				sourceCode.push(this.makeCustomValidator({vName: resVar, path: customPath, schema: rule.schema, context, messages: rule.messages, ruleIndex: rule.index}));
+
 			} else {
 				sourceCode.push(this.wrapRequiredCheckSourceCode(rule));
 			}
diff --git a/test/rules/multi.spec.js b/test/rules/multi.spec.js
index e1ce797..1979dc4 100644
--- a/test/rules/multi.spec.js
+++ b/test/rules/multi.spec.js
@@ -2,7 +2,7 @@
 
 const Validator = require("../../lib/validator");
 const v = new Validator({
-	useNewCustomCheckerFunction: true
+	useNewCustomCheckerFunction: true,
 });
 
 describe("Test rule: multi", () => {
@@ -28,7 +28,7 @@ describe("Test rule: multi", () => {
 		expect(fn).toBeCalledWith("s", [], schema.rules[0], "$$root", null, expect.any(Object));
 	});
 
-	it("should value equals to other field", () => {
-		// TODO: move from validator.spec.js
-	});
+	// it("should value equals to other field", () => {
+	// 	// TODO: move from validator.spec.js
+	// });
 });
diff --git a/test/validator.spec.js b/test/validator.spec.js
index 880f1f5..90c5062 100644
--- a/test/validator.spec.js
+++ b/test/validator.spec.js
@@ -428,7 +428,7 @@ describe("Test custom validation v1", () => {
 	});
 });
 
-describe("Test custom validation v2", () => {
+describe("Test custom validation", () => {
 	const v = new Validator({
 		useNewCustomCheckerFunction: true,
 		messages: {
@@ -468,6 +468,25 @@ describe("Test custom validation v2", () => {
 		expect(check({num: 18})[0].type).toEqual("numberMax");
 		expect(check({num: 13})[0].type).toEqual("evenNumber");
 	});
+
+	it("should call checker function after build-in rule", () => {
+		// depended to number rule
+		const checkerFn = jest.fn((v) => v);
+
+		const schema = {
+			a: {
+				type: "number",
+				convert: true,
+				custom: checkerFn
+			}
+		};
+		const check = v.compile(schema);
+		const o = { a: "123" };
+
+		expect(check(o)).toBe(true);
+		expect(checkerFn).toBeCalledTimes(1);
+		expect(checkerFn.mock.calls[0][0]).toBe(123);
+	});
 });
 
 describe("Test default settings", () => {