diff --git a/test/node/bigint.test.ts b/test/node/bigint.test.ts
index fcc95790..b1e17a83 100644
--- a/test/node/bigint.test.ts
+++ b/test/node/bigint.test.ts
@@ -1,4 +1,4 @@
-import { BSON, BSONError } from '../register-bson';
+import { BSON, EJSON, BSONError } from '../register-bson';
 import { bufferFromHexArray } from './tools/utils';
 import { expect } from 'chai';
 import { BSON_DATA_LONG } from '../../src/constants';
@@ -263,4 +263,92 @@ describe('BSON BigInt support', function () {
       expect(serializedMap).to.deep.equal(expectedSerialization);
     });
   });
+
+  describe('EJSON.stringify()', function () {
+    it('truncates bigint values when they are outside the range [BSON_INT64_MIN, BSON_INT64_MAX] in canonical mode', function () {
+      const numbers = { a: 2n ** 64n + 1n, b: -(2n ** 64n) - 1n };
+      const serialized = EJSON.stringify(numbers, { relaxed: false });
+      expect(serialized).to.equal('{"a":{"$numberLong":"1"},"b":{"$numberLong":"-1"}}');
+    });
+
+    it('truncates bigint values in the same way as BSON.serialize in canonical mode', function () {
+      const number = { a: 0x1234_5678_1234_5678_9999n };
+      const stringified = EJSON.stringify(number, { relaxed: false });
+      const serialized = BSON.serialize(number);
+
+      const VALUE_OFFSET = 7;
+      const dataView = BSONDataView.fromUint8Array(serialized);
+      const serializedValue = dataView.getBigInt64(VALUE_OFFSET, true);
+      const parsed = JSON.parse(stringified);
+
+      expect(parsed).to.have.property('a');
+      expect(parsed['a']).to.have.property('$numberLong');
+      expect(parsed.a.$numberLong).to.equal(0x5678_1234_5678_9999n.toString());
+
+      expect(parsed.a.$numberLong).to.equal(serializedValue.toString());
+    });
+
+    it('truncates bigint values in the same way as BSON.serialize in relaxed mode', function () {
+      const number = { a: 0x1234_0000_1234_5678_9999n }; // Ensure that the truncated number can be exactly represented as a JS number
+      const stringified = EJSON.stringify(number, { relaxed: true });
+      const serializedDoc = BSON.serialize(number);
+
+      const VALUE_OFFSET = 7;
+      const dataView = BSONDataView.fromUint8Array(serializedDoc);
+      const parsed = JSON.parse(stringified);
+
+      expect(parsed).to.have.property('a');
+      expect(parsed.a).to.equal(0x0000_1234_5678_9999);
+
+      expect(parsed.a).to.equal(Number(dataView.getBigInt64(VALUE_OFFSET, true)));
+    });
+
+    it('serializes bigint values to numberLong in canonical mode', function () {
+      const number = { a: 2n };
+      const serialized = EJSON.stringify(number, { relaxed: false });
+      expect(serialized).to.equal('{"a":{"$numberLong":"2"}}');
+    });
+
+    it('serializes bigint values to Number in relaxed mode', function () {
+      const number = { a: 10000n };
+      const serialized = EJSON.stringify(number, { relaxed: true });
+      expect(serialized).to.equal('{"a":10000}');
+    });
+
+    it('loses precision when serializing bigint values outside of range [Number.MIN_SAFE_INTEGER, Number.MAX_SAFE_INTEGER] in relaxed mode', function () {
+      const numbers = { a: -(2n ** 53n) - 1n, b: 2n ** 53n + 2n };
+      const serialized = EJSON.stringify(numbers, { relaxed: true });
+      expect(serialized).to.equal('{"a":-9007199254740992,"b":9007199254740994}');
+    });
+
+    it('produces bigint strings that pass loose equality checks with native bigint values that are are 64 bits wide or less', function () {
+      const number = { a: 12345n };
+      const serialized = EJSON.stringify(number, { relaxed: false });
+      const parsed = JSON.parse(serialized);
+      // eslint-disable-next-line eqeqeq
+      expect(parsed.a.$numberLong == 12345n).true;
+    });
+
+    it('produces bigint strings that are equal to the strings generated when using BigInt.toString when the bigint values used are 64 bits wide or less', function () {
+      const number = { a: 12345n };
+      const serialized = EJSON.stringify(number, { relaxed: false });
+      const parsed = JSON.parse(serialized);
+      expect(parsed.a.$numberLong).to.equal(12345n.toString());
+    });
+
+    it('produces bigint strings that fail loose equality checks with native bigint values that are more than 64 bits wide', function () {
+      const number = { a: 0x1234_5678_1234_5678_9999n };
+      const serialized = EJSON.stringify(number, { relaxed: false });
+      const parsed = JSON.parse(serialized);
+      // eslint-disable-next-line eqeqeq
+      expect(parsed.a.$numberLong == 0x1234_5678_1234_5678_9999n).false;
+    });
+
+    it('produces bigint strings that are not equal to the strings generated when using BigInt.toString when the bigint values used are more than 64 bits wide', function () {
+      const number = { a: 0x1234_5678_1234_5678_9999n };
+      const serialized = EJSON.stringify(number, { relaxed: false });
+      const parsed = JSON.parse(serialized);
+      expect(parsed.a.$numberLong).to.not.equal(0x1234_5678_1234_5678_9999n.toString());
+    });
+  });
 });
diff --git a/test/node/extended_json.test.ts b/test/node/extended_json.test.ts
index 936a24a3..3e25c559 100644
--- a/test/node/extended_json.test.ts
+++ b/test/node/extended_json.test.ts
@@ -2,7 +2,6 @@ import * as BSON from '../register-bson';
 const EJSON = BSON.EJSON;
 import * as vm from 'node:vm';
 import { expect } from 'chai';
-import { BSONDataView } from '../../src/utils/byte_utils';
 import { BSONError } from '../../src';
 
 // BSON types
@@ -182,92 +181,6 @@ describe('Extended JSON', function () {
     expect(EJSON.parse(serialized)).to.deep.equal(numbers);
   });
 
-  it('truncates bigint values when they are outside the range [BSON_INT64_MIN, BSON_INT64_MAX] in canonical mode', function () {
-    const numbers = { a: 2n ** 64n + 1n, b: -(2n ** 64n) - 1n };
-    const serialized = EJSON.stringify(numbers, { relaxed: false });
-    expect(serialized).to.equal('{"a":{"$numberLong":"1"},"b":{"$numberLong":"-1"}}');
-  });
-
-  it('truncates bigint values in the same way as BSON.serialize in canonical mode', function () {
-    const number = { a: 0x1234_5678_1234_5678_9999n };
-    const stringified = EJSON.stringify(number, { relaxed: false });
-    const serialized = BSON.serialize(number);
-
-    const VALUE_OFFSET = 7;
-    const dataView = BSONDataView.fromUint8Array(serialized);
-    const serializedValue = dataView.getBigInt64(VALUE_OFFSET, true);
-    const parsed = JSON.parse(stringified);
-
-    expect(parsed).to.have.property('a');
-    expect(parsed['a']).to.have.property('$numberLong');
-    expect(parsed.a.$numberLong).to.equal(0x5678_1234_5678_9999n.toString());
-
-    expect(parsed.a.$numberLong).to.equal(serializedValue.toString());
-  });
-
-  it('truncates bigint values in the same way as BSON.serialize in relaxed mode', function () {
-    const number = { a: 0x1234_0000_1234_5678_9999n }; // Ensure that the truncated number can be exactly represented as a JS number
-    const stringified = EJSON.stringify(number, { relaxed: true });
-    const serializedDoc = BSON.serialize(number);
-
-    const VALUE_OFFSET = 7;
-    const dataView = BSONDataView.fromUint8Array(serializedDoc);
-    const parsed = JSON.parse(stringified);
-
-    expect(parsed).to.have.property('a');
-    expect(parsed.a).to.equal(0x0000_1234_5678_9999);
-
-    expect(parsed.a).to.equal(Number(dataView.getBigInt64(VALUE_OFFSET, true)));
-  });
-
-  it('serializes bigint values to numberLong in canonical mode', function () {
-    const number = { a: 2n };
-    const serialized = EJSON.stringify(number, { relaxed: false });
-    expect(serialized).to.equal('{"a":{"$numberLong":"2"}}');
-  });
-
-  it('serializes bigint values to Number in relaxed mode', function () {
-    const number = { a: 10000n };
-    const serialized = EJSON.stringify(number, { relaxed: true });
-    expect(serialized).to.equal('{"a":10000}');
-  });
-
-  it('loses precision when serializing bigint values outside of range [Number.MIN_SAFE_INTEGER, Number.MAX_SAFE_INTEGER] in relaxed mode', function () {
-    const numbers = { a: -(2n ** 53n) - 1n, b: 2n ** 53n + 2n };
-    const serialized = EJSON.stringify(numbers, { relaxed: true });
-    expect(serialized).to.equal('{"a":-9007199254740992,"b":9007199254740994}');
-  });
-
-  it('produces bigint strings that pass loose equality checks with native bigint values that are are 64 bits wide or less', function () {
-    const number = { a: 12345n };
-    const serialized = EJSON.stringify(number, { relaxed: false });
-    const parsed = JSON.parse(serialized);
-    // eslint-disable-next-line eqeqeq
-    expect(parsed.a.$numberLong == 12345n).true;
-  });
-
-  it('produces bigint strings that are equal to the strings generated when using BigInt.toString when the bigint values used are 64 bits wide or less', function () {
-    const number = { a: 12345n };
-    const serialized = EJSON.stringify(number, { relaxed: false });
-    const parsed = JSON.parse(serialized);
-    expect(parsed.a.$numberLong).to.equal(12345n.toString());
-  });
-
-  it('produces bigint strings that fail loose equality checks with native bigint values that are more than 64 bits wide', function () {
-    const number = { a: 0x1234_5678_1234_5678_9999n };
-    const serialized = EJSON.stringify(number, { relaxed: false });
-    const parsed = JSON.parse(serialized);
-    // eslint-disable-next-line eqeqeq
-    expect(parsed.a.$numberLong == 0x1234_5678_1234_5678_9999n).false;
-  });
-
-  it('produces bigint strings that are not equal to the strings generated when using BigInt.toString when the bigint values used are more than 64 bits wide', function () {
-    const number = { a: 0x1234_5678_1234_5678_9999n };
-    const serialized = EJSON.stringify(number, { relaxed: false });
-    const parsed = JSON.parse(serialized);
-    expect(parsed.a.$numberLong).to.not.equal(0x1234_5678_1234_5678_9999n.toString());
-  });
-
   it('should correctly parse null values', function () {
     expect(EJSON.parse('null')).to.be.null;
     expect(EJSON.parse('[null]')[0]).to.be.null;