Pilot on final approach to a non towered airport reported an experimental aircraft had departed without communicating via CTAF resulting in a NMAC.

Narrative

I was inbound to LUD behind Aircraft Z on final. Aircraft Z had landed and was taxiing off runway and I was about 1.2 miles out. I crossed highway to land on Runway 35 and a little airplane crossed the hold short line and jumped onto the runway. I made radio calls stating I was on a short final for 35. No response from the aircraft and he proceeded to initiate take off. I performed a go around and started the process for that. I was able to look down and said Aircraft Y was still in process of taking off as I was trying to regain airspeed and climb out. Still no radio calls from Aircraft Y. Other aircraft were also talking to the aircraft with no luck on answering. I aggressively turned out to the east toward the traffic pattern for Runway 35 and from my screen shot on foreflight; we were around 300' apart at this point. The impeding aircraft departed and flew an incorrect pattern on the west side of the airport and I proceeded to go downwind on the east; eventually having to tear drop into 35 downwind from the east due to Aircraft Y coming toward the east. After this; I had an uneventful landing. I believe the problem occurred due to poor awareness of the other pilot and no radio communication from the other pilot.