Anyone who has created a website or a backend service would want them to be fast, robust, and perform well all the time. Good design, engineering excellence, and proper processes will contribute to these goals. Yet, what is often overlooked is the importance monitoring tools have on a project's success. Hence the budget for some type of monitoring tool is often marked as optional rather than a must-have. This is our motivation. Proper monitoring tools must be set up from the very beginning. Any development team should integrate monitoring tools in their development process. Then they should extend it into production deployment. With this in mind, we created Monika, a synthetic monitoring tool. Monika is an open-source and free synthetic monitoring command-line application. The name Monika stands for “Monitoring Berkala”, which means “periodic monitoring” in the Indonesian language. With Monika, you can add as many websites as you want to monitor. You can monitor several undesirable events such as service outages or slow services. In addition, you can configure Monika to send notifications of the incidents on your services through your favorite communication tools like SMTP mail, Telegram, WhatsApp (It’s free!), etc. There are plenty of free monitoring tools online, but many fall short of our requirements. Free uptime monitors exist, but they only ping for service availability. Most users don't use services only with pings. There are also plenty of real-time monitoring tools. These tools need real users, which makes them less suitable during development. Monika however, can synthesize usage scenarios during development, and you can use the same scenarios in production. Synthetic monitoring tools enable you to generate complex usage flows for quality assurance. Those same flows, later on, can be deployed to check the production environment. All without the need to install agents or third-party libraries.