He started his programming journey in Visual Basic (.NET) at seven years old. At the age of fourteen, he formed an interest in web development. Throughout his life, he started a couple of businesses. Most of which never really came to fruition or failed early on. These were Instagram automation tools, game server hosting (Penalty-Networks, formerly Cosmos-Networks), a record label (Deep Sound Records).

His current and most successful business, Anti-Joy, was originally a subsidiary of Deep Sound Records until he decided to dissolve Deep Sound Records and focus on Anti-Joy, due to his belief in the vision the project shared. When Anti-Joy launched, he was just eighteen years old. One of the most essential elements of all his businesses was superior customer service and transparency.

Jonas Madsen believes Anti-Joy became successful due to his vast belief and dedication to the business. Currently, he is actively expanding and developing his business and developing a subsidiary of Anti-Joy, which will be a worldwide music merchandise and download store named Shusic. He's also working on a book on climate change about how environmentalists neglect science in favor of emotions.