log4j configuration

        val ctx = LoggerContext.getContext(false)
        val root = ctx.rootLogger
        val cfg = ctx.configuration

        val layout = PatternLayout.newBuilder()
            .withPattern("[%d{HH:mm:ss}] [%25.25t] [%level]: %msg%n")
            .withCharset(StandardCharsets.UTF_8)
            .withAlwaysWriteExceptions(true)
            .withConfiguration(cfg)
            .build()

        val policy = OnStartupTriggeringPolicy.createPolicy(0)

        val strategy = DefaultRolloverStrategy.newBuilder()
            .withMax("10")
            .withMin("1")
            .withFileIndex("min")
            .withConfig(cfg)
            .build()

        val fileAppender = (
                RollingFileAppender.newBuilder<RollingFileAppenderBuilder>() as RollingFileAppender.Builder<RollingFileAppenderBuilder>
        ).apply {
            name = "File"
            configuration = cfg
            setLayout(layout)

            withFileName(File("latest.log").absolutePath.toString())
            withFilePattern(File("latestn.log").absolutePath.toString() + ".%i")
            withAppend(true)
            withImmediateFlush(true)
            withPolicy(policy)
            withStrategy(strategy)
        }.build()

        fileAppender.start()

        cfg.addAppender(fileAppender)
        root.addAppender(fileAppender)

        root.info("test")