Koivisto, the open source chess engine by Kim Kåhre and Finn Eggers, is the sole leader of TCEC S21 QL after round 2. Consecutive wins vs Invictus and Bagatur give Koivisto 2,0/2.
Written in C++ and first released in September 2020, Koivisto is making a good progress. It played TCEC L4 in Season 20 and entered top 30 in the first TCEC Swiss.
Update: Koivisto just won its 3rd consecutive game and will keep the lead after R3. Replay the game here
Standings after R2
1. Koivisto 2,0/2
2-4. Classic Ara, Stash, Drofa 1,5/2
5-10. Booot, Amoeba, Cheng, Invictus, Bagatur, Nirvana 1,0/2
11-13. TomitankChess, Cheese, Berserk 0,5/2
14. Francesca 0/2