diff --git a/test/unit/testutiljson.cpp b/test/unit/testutiljson.cpp
new file mode 100644
index 0000000..9103af3
--- /dev/null
+++ b/test/unit/testutiljson.cpp
@@ -0,0 +1,570 @@
+/*
+ * Copyright (C) 2022 Riyyi
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#include <cstddef>    // nullptr_t
+#include <cstdint>    // uint32_t
+#include <functional> // function
+#include <map>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+#include "macro.h"
+#include "testcase.h"
+#include "testsuite.h"
+#include "util/json/array.h"
+#include "util/json/job.h"
+#include "util/json/lexer.h"
+#include "util/json/parser.h"
+#include "util/json/serializer.h"
+#include "util/json/value.h"
+
+#define DONT_PRINT_PARSER_ERRORS
+
+#ifndef DONT_PRINT_PARSER_ERRORS
+#define EXEC(x) x
+#else
+#define EXEC(x)                                   \
+	stdout = Test::TestSuite::the().outputNull(); \
+	x;                                            \
+	stdout = Test::TestSuite::the().outputStd();
+#endif
+
+std::vector<Json::Token> lex(const std::string& input)
+{
+	EXEC(
+		Json::Job job(input);
+		Json::Lexer lexer(&job);
+		lexer.analyze(););
+	return *job.tokens();
+}
+
+Json::Value parse(const std::string& input)
+{
+	EXEC(
+		Json::Job job(input);
+		Json::Lexer lexer(&job);
+		lexer.analyze(););
+
+	if (!job.success()) {
+		return nullptr;
+	}
+
+	EXEC(
+		Json::Parser parser(&job);
+		Json::Value json = parser.parse(););
+
+	if (!job.success()) {
+		return nullptr;
+	}
+
+	return json;
+}
+
+std::string serialize(const std::string& input, uint32_t indent = 0)
+{
+	EXEC(
+		auto json = Json::Value::parse(input););
+	return json.dump(indent);
+}
+
+// -----------------------------------------
+
+TEST_CASE(JsonLexer)
+{
+	std::vector<Json::Token> tokens;
+
+	// Literal
+
+	tokens = lex("true");
+	EXPECT_EQ(tokens.size(), 1);
+	EXPECT_EQ(tokens[0].symbol, "true");
+	EXPECT(tokens[0].type == Json::Token::Type::Literal);
+
+	tokens = lex("false");
+	EXPECT_EQ(tokens.size(), 1);
+	EXPECT_EQ(tokens[0].symbol, "false");
+	EXPECT(tokens[0].type == Json::Token::Type::Literal);
+
+	tokens = lex("null");
+	EXPECT_EQ(tokens.size(), 1);
+	EXPECT_EQ(tokens[0].symbol, "null");
+	EXPECT(tokens[0].type == Json::Token::Type::Literal);
+
+	// Number
+
+	tokens = lex("3.14");
+	EXPECT_EQ(tokens.size(), 1);
+	EXPECT_EQ(tokens[0].symbol, "3.14");
+	EXPECT(tokens[0].type == Json::Token::Type::Number);
+
+	tokens = lex("-3.14e+2");
+	EXPECT_EQ(tokens.size(), 1);
+	EXPECT_EQ(tokens[0].symbol, "-3.14e+2");
+	EXPECT(tokens[0].type == Json::Token::Type::Number);
+
+	tokens = lex("+3.14");
+	EXPECT_EQ(tokens.size(), 1);
+	EXPECT_EQ(tokens[0].symbol, "+");
+	EXPECT(tokens[0].type == Json::Token::Type::None);
+
+	// String
+
+	tokens = lex(R"("a string")");
+	EXPECT_EQ(tokens.size(), 1);
+	EXPECT_EQ(tokens[0].symbol, "a string");
+	EXPECT(tokens[0].type == Json::Token::Type::String);
+
+	tokens = lex(R"("a string""another string")");
+	EXPECT_EQ(tokens.size(), 2);
+	EXPECT_EQ(tokens[0].symbol, "a string");
+	EXPECT_EQ(tokens[1].symbol, "another string");
+	EXPECT(tokens[0].type == Json::Token::Type::String);
+
+	tokens = lex("\"a string\nwill break on the newline symbol\"");
+	EXPECT_EQ(tokens.size(), 1);
+	EXPECT_EQ(tokens[0].symbol, "a string");
+	EXPECT(tokens[0].type == Json::Token::Type::String);
+
+	// Array
+
+	tokens = lex("[]");
+	EXPECT_EQ(tokens.size(), 2);
+	EXPECT_EQ(tokens[0].symbol, "[");
+	EXPECT_EQ(tokens[1].symbol, "]");
+
+	tokens = lex("[\n\n\n]");
+	EXPECT_EQ(tokens.size(), 2);
+	EXPECT_EQ(tokens[0].symbol, "[");
+	EXPECT_EQ(tokens[1].symbol, "]");
+
+	// Object
+
+	tokens = lex("{}");
+	EXPECT_EQ(tokens.size(), 2);
+	EXPECT_EQ(tokens[0].symbol, "{");
+	EXPECT_EQ(tokens[1].symbol, "}");
+
+	tokens = lex("{\n\n\n}");
+	EXPECT_EQ(tokens.size(), 2);
+	EXPECT_EQ(tokens[0].symbol, "{");
+	EXPECT_EQ(tokens[1].symbol, "}");
+}
+
+TEST_CASE(JsonParser)
+{
+	Json::Value json;
+
+	json = parse("null");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse("true");
+	EXPECT_EQ(json.size(), 1);
+	EXPECT_EQ(json.type(), Json::Value::Type::Bool);
+
+	json = parse("false");
+	EXPECT_EQ(json.size(), 1);
+	EXPECT_EQ(json.type(), Json::Value::Type::Bool);
+
+	json = parse("3.14");
+	EXPECT_EQ(json.size(), 1);
+	EXPECT_EQ(json.type(), Json::Value::Type::Number);
+
+	json = parse(R"("a string")");
+	EXPECT_EQ(json.size(), 1);
+	EXPECT_EQ(json.type(), Json::Value::Type::String);
+
+	// Array
+
+	json = parse("[");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse("[ 123");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse("[ 123,");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse("[ 123, ]");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse("[ 123 456 ]");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse("[]");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Array);
+
+	json = parse(R"([ "element", 3.14 ])");
+	EXPECT_EQ(json.size(), 2);
+	EXPECT_EQ(json.type(), Json::Value::Type::Array);
+
+	// Object
+
+	json = parse("{");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse(R"({ "name")");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse(R"({ "name":)");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse(R"({ "name":,)");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse(R"({ "name":"value")");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse(R"({ "name":"value",)");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse(R"({ "name":"value", })");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse(R"({ "name" "value" })");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse(R"({ 123 })");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse("{}");
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Object);
+
+	json = parse(R"({ "name": "value", "name2": 3.14 })");
+	EXPECT_EQ(json.size(), 2);
+	EXPECT_EQ(json.type(), Json::Value::Type::Object);
+
+	// Multiple root elements
+
+	json = parse("54 false");
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse("3.14, 666");
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = parse("true\nfalse");
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+}
+
+TEST_CASE(JsonToJsonValue)
+{
+	Json::Value json;
+
+	json = {};
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = nullptr;
+	EXPECT_EQ(json.size(), 0);
+	EXPECT_EQ(json.type(), Json::Value::Type::Null);
+
+	json = true;
+	EXPECT_EQ(json.size(), 1);
+	EXPECT_EQ(json.type(), Json::Value::Type::Bool);
+
+	json = false;
+	EXPECT_EQ(json.size(), 1);
+	EXPECT_EQ(json.type(), Json::Value::Type::Bool);
+
+	json = 666;
+	EXPECT_EQ(json.size(), 1);
+	EXPECT_EQ(json.type(), Json::Value::Type::Number);
+
+	json = 3.14;
+	EXPECT_EQ(json.size(), 1);
+	EXPECT_EQ(json.type(), Json::Value::Type::Number);
+
+	const char* characters = "my string";
+	json = characters;
+	EXPECT_EQ(json.size(), 1);
+	EXPECT_EQ(json.type(), Json::Value::Type::String);
+
+	std::string string = "my string";
+	json = string;
+	EXPECT_EQ(json.size(), 1);
+	EXPECT_EQ(json.type(), Json::Value::Type::String);
+
+	// Nested Array with multiple types
+	json = { "element", 3.14, true, nullptr, { "nested element", { "more nesting", { 1, 2, 3, "yes" } } } };
+	EXPECT_EQ(json.size(), 5);
+	EXPECT_EQ(json.type(), Json::Value::Type::Array);
+
+	// Nested Object with multiple types
+	json = { { "name", "value" }, { "name2", 3.14 }, { "name3", true }, { "name4", nullptr }, { "name5", { { "nested name", "value" } } } };
+	EXPECT_EQ(json.size(), 5);
+	EXPECT_EQ(json.type(), Json::Value::Type::Object);
+
+	// Array with singular type
+	std::vector<std::string> vector = { "element", "element2", "element3" };
+	json = vector;
+	EXPECT_EQ(json.size(), 3);
+	EXPECT_EQ(json.type(), Json::Value::Type::Array);
+
+	// Object with singular type
+	std::map<std::string, std::string> map = { { "name", "value" }, { "name2", "value2" } };
+	json = map;
+	EXPECT_EQ(json.size(), 2);
+	EXPECT_EQ(json.type(), Json::Value::Type::Object);
+
+	// Object with singular type
+	std::unordered_map<std::string, std::string> unorderedMap = { { "name", "value" }, { "name2", "value2" } };
+	json = unorderedMap;
+	EXPECT_EQ(json.size(), 2);
+	EXPECT_EQ(json.type(), Json::Value::Type::Object);
+}
+
+TEST_CASE(JsonFromJsonValue)
+{
+	Json::Value json;
+
+	json = nullptr;
+	EXPECT_EQ(json.get<std::nullptr_t>(), nullptr);
+
+	json = true;
+	EXPECT_EQ(json.get<bool>(), true);
+
+	json = false;
+	EXPECT_EQ(json.get<bool>(), false);
+
+	json = 666;
+	EXPECT_EQ(json.get<int>(), 666);
+
+	json = 3.14;
+	EXPECT_EQ(json.get<double>(), 3.14);
+
+	std::string string;
+	json = "my string";
+	json.getTo(string);
+	EXPECT_EQ(string, "my string");
+	EXPECT_EQ(json.get<std::string>(), "my string");
+
+	// Array with singular type
+	json = { "element", "element2" };
+	EXPECT_EQ(json[0].get<std::string>(), "element");
+	EXPECT_EQ(json.at(1).get<std::string>(), "element2");
+	auto array = json.get<std::vector<std::string>>();
+	EXPECT_EQ(array.size(), 2);
+	EXPECT_EQ(array[0], "element");
+	EXPECT_EQ(array[1], "element2");
+
+	// Array with multiple types
+	json = { "string", 3.14, true, nullptr };
+	EXPECT_EQ(json[0].get<std::string>(), "string");
+	EXPECT_EQ(json.at(1).get<double>(), 3.14);
+	EXPECT_EQ(json[2].get<bool>(), true);
+	EXPECT_EQ(json[3].get<std::nullptr_t>(), nullptr);
+	auto valueArray = json.get<std::vector<Json::Value>>();
+	EXPECT_EQ(valueArray.size(), 4);
+	EXPECT_EQ(valueArray[0].get<std::string>(), "string");
+	EXPECT_EQ(valueArray[1].get<double>(), 3.14);
+	EXPECT_EQ(valueArray[2].get<bool>(), true);
+	EXPECT_EQ(valueArray[3].get<std::nullptr_t>(), nullptr);
+
+	// Nested Array with multiple types
+	json = {
+		"value",
+		{
+			"thing",
+			666,
+		},
+		{
+			{
+				3.14,
+			},
+		}
+	};
+	EXPECT_EQ(json[0].get<std::string>(), "value");
+	EXPECT_EQ(json.at(1)[0].get<std::string>(), "thing");
+	EXPECT_EQ(json[1].at(1).get<int>(), 666);
+	EXPECT_EQ(json[2][0][0].get<double>(), 3.14);
+
+	// Object with singular type
+	json = { { "name", "value" }, { "name2", "value2" } };
+	EXPECT_EQ(json["name"].get<std::string>(), "value");
+	EXPECT_EQ(json.at("name2").get<std::string>(), "value2");
+	auto object = json.get<std::map<std::string, std::string>>();
+	EXPECT_EQ(object.size(), 2);
+	EXPECT_EQ(object["name"], "value");
+	EXPECT_EQ(object["name2"], "value2");
+	auto unorderedObject = json.get<std::unordered_map<std::string, std::string>>();
+	EXPECT_EQ(unorderedObject.size(), 2);
+	EXPECT_EQ(unorderedObject["name"], "value");
+	EXPECT_EQ(unorderedObject["name2"], "value2");
+
+	// Object with multiple types
+	json = { { "name", "value" }, { "name2", 3.14 }, { "name3", true }, { "name4", nullptr } };
+	EXPECT_EQ(json["name"].get<std::string>(), "value");
+	EXPECT_EQ(json.at("name2").get<double>(), 3.14);
+	EXPECT_EQ(json["name3"].get<bool>(), true);
+	EXPECT_EQ(json["name4"].get<std::nullptr_t>(), nullptr);
+	auto valueObject = json.get<std::map<std::string, Json::Value>>();
+	EXPECT_EQ(valueObject.size(), 4);
+	EXPECT_EQ(valueObject["name"].get<std::string>(), "value");
+	EXPECT_EQ(valueObject["name2"].get<double>(), 3.14);
+	EXPECT_EQ(valueObject["name3"].get<bool>(), true);
+	EXPECT_EQ(valueObject["name4"].get<std::nullptr_t>(), nullptr);
+
+	// Nested Object with multiple types
+	json = {
+		{
+			"name",
+			"value",
+		},
+		{
+			"nest 1-deep",
+			{ {
+				"number",
+				1,
+			} },
+		},
+		{
+			"nest 2-deep",
+			{ {
+				"nest 1-deep",
+				{ {
+					"bool",
+					true,
+				} },
+			} },
+		},
+	};
+	EXPECT_EQ(json["name"].get<std::string>(), "value");
+	EXPECT_EQ(json["nest 1-deep"]["number"].get<int>(), 1);
+	EXPECT_EQ(json["nest 2-deep"]["nest 1-deep"]["bool"].get<bool>(), true);
+}
+
+TEST_CASE(JsonImplicitConversion)
+{
+	Json::Value array;
+	array[0];
+	EXPECT_EQ(array.type(), Json::Value::Type::Array);
+
+	Json::Value arrayEmplace;
+	arrayEmplace.emplace_back("element");
+	arrayEmplace.emplace_back({ "nested element" });
+	EXPECT_EQ(arrayEmplace.type(), Json::Value::Type::Array);
+	EXPECT_EQ(arrayEmplace[1].type(), Json::Value::Type::Array);
+
+	Json::Value object;
+	object[""];
+	EXPECT_EQ(object.type(), Json::Value::Type::Object);
+
+	Json::Value objectEmplace;
+	objectEmplace.emplace("name", "value");
+	objectEmplace.emplace("name2", { { "nested name", "value" } });
+	EXPECT_EQ(objectEmplace.type(), Json::Value::Type::Object);
+	EXPECT_EQ(objectEmplace["name2"].type(), Json::Value::Type::Object);
+}
+
+TEST_CASE(JsonSerializer)
+{
+	EXPECT_EQ(serialize(""), "null");
+	EXPECT_EQ(serialize("null"), "null");
+	EXPECT_EQ(serialize("true"), "true");
+	EXPECT_EQ(serialize("false"), "false");
+	EXPECT_EQ(serialize("3.14"), "3.14");
+	EXPECT_EQ(serialize(R"("string")"), R"("string")");
+
+	EXPECT_EQ(serialize("\n\n\n"), "null");
+	EXPECT_EQ(serialize("null\n"), "null");
+	EXPECT_EQ(serialize("true\n"), "true");
+	EXPECT_EQ(serialize("false\n"), "false");
+	EXPECT_EQ(serialize("3.14\n"), "3.14");
+	// clang-format off
+	EXPECT_EQ(serialize(R"("string")" "\n"), R"("string")");
+	// clang-format on
+
+	EXPECT_EQ(serialize("[\n\n\n]"), "[]");
+	EXPECT_EQ(serialize("[null]"), "[null]");
+	EXPECT_EQ(serialize("[true]"), "[true]");
+	EXPECT_EQ(serialize("[false]"), "[false]");
+	EXPECT_EQ(serialize("[3.14]"), "[3.14]");
+	EXPECT_EQ(serialize(R"(["string"])"), R"(["string"])");
+
+	EXPECT_EQ(serialize("[\n\n\n]", 4), "[\n]");
+	EXPECT_EQ(serialize("[null]", 4), "[\n    null\n]");
+	EXPECT_EQ(serialize("[true]", 4), "[\n    true\n]");
+	EXPECT_EQ(serialize("[false]", 4), "[\n    false\n]");
+	EXPECT_EQ(serialize("[3.14]", 4), "[\n    3.14\n]");
+	// clang-format off
+	EXPECT_EQ(serialize(R"(["string"])", 4), "[\n    " R"("string")" "\n]");
+	// clang-format on
+
+	// Check for trailing comma on last array element
+	EXPECT_EQ(serialize(R"([1])"), R"([1])");
+	EXPECT_EQ(serialize(R"([1,2])"), R"([1,2])");
+	EXPECT_EQ(serialize(R"([1,2,3])"), R"([1,2,3])");
+
+	// Check for trailing comma on last object member
+	EXPECT_EQ(serialize(R"({"n1":"v1"})"), R"({"n1":"v1"})");
+	EXPECT_EQ(serialize(R"({"n1":"v1", "n2":"v2"})"), R"({"n1":"v1","n2":"v2"})");
+	EXPECT_EQ(serialize(R"({"n1":"v1", "n2":"v2", "n3":"v3"})"), R"({"n1":"v1","n2":"v2","n3":"v3"})");
+
+	// clang-format off
+	EXPECT_EQ(serialize(R"({
+	"object member one": [
+		"array element one"
+	],
+	"object member two": [
+		"array element one",
+		"array element two"
+	],
+	"object member three": [
+		"array element one",
+		2,
+		3.0,
+		4.56,
+		true,
+		false,
+		null
+	],
+	"object member four": 3.14,
+	"object member five": "value five",
+	"object member six": null,
+	"object member seven": { "no": 0 }
+})", 4), R"({
+    "object member five": "value five",
+    "object member four": 3.14,
+    "object member one": [
+        "array element one"
+    ],
+    "object member seven": {
+        "no": 0
+    },
+    "object member six": null,
+    "object member three": [
+        "array element one",
+        2,
+        3,
+        4.56,
+        true,
+        false,
+        null
+    ],
+    "object member two": [
+        "array element one",
+        "array element two"
+    ]
+})");
+	// clang-format on
+}