How to detect cheater or engine user ?

Hello sir/mam,I realize tht there are some players who are use chess engine to won the game.It could be hear to strange bt what happen if any player use chess engine & u cant detect him/her ? In ur forum topic i jst read the topics bt seriously, u need to improve ur system.In the forum,I read tht if any player u hv doubt tht he/she used chess engine,u can analysis the game,bt in the analysis when i checked some games which is completely used engine bt engine user defend itself by 2-3 mistakes & 1 blunder.& according to ur policy if any player has 0 blunder,0 mistakes it is/was engine user,not any 1-2 blunder/mistakes player.& some players geting off after every move to check their game on engine etc. etc.

Plz reply if u think about this serious topic.

even if they have 0 blunders and 0 mistakes, it doesn't necesarrily mean it's a cheater. If it's in a fast game like Bullet or Blitz, then the probability is higher, than if it's in rapid or classical.
Also, whenever you report a player, the moderators have acces to tools that we don't. (Probably a much more detailed Chess Insight than the ones we have)

Sooner or later a cheater will be exposed and enveryone will know. They can cheat for a while but not all the time.

Cheaters who play without mistakes can be easily revealed by Lichess auto-detect system. The main problem is that it's almost impossible to detect cheater who makes most of his moves like honest player but in critical position find two-three strong moves with engine assistance. That is why some people completly avoid playing Rapid and Classical games on the internet.

Do you think you can play games where you move until to a certain point, ask the engine and afterwards play on alone? That’s the way all the paranoids think. Do it a couple of times successfully and you‘re dead as a dodo.

Here you can find some general points:

https://www.reddit.com/r/chess/comments/9s9ml8/how_does_chesscom_and_lichess_deal_with_gms/e8n9uwg

"NikitaLyashenko
Cheaters who play without mistakes can be easily revealed by Lichess auto-detect system. The main problem is that it's almost impossible to detect cheater who makes most of his moves like honest player but in critical position find two-three strong moves with engine assistance. That is why some people completly avoid playing Rapid and Classical games on the internet."

Tht is the main problem of lichess server.Sometime it can't detect the cheaters,if u report tht player...lichess hardly blocked their account bcoz if u analysis the game u found 1/2 blunder ,3-4 mistakes.& the major thing is...if u in a winning position,ur opponent got offline & suddenly it came & win the game within 5-6 moves.

@AB17 Agree...this is the shortcoming of all websites though.

I don't know that I'll ever understand why people care so much. You lose a game to a cheater... so what? At most, you've lost a little time, nothing else. And you've had the opportunity to play (unknowingly, unexpectedly) against a stronger opponent (maybe even a computer). Think of it as a training exercise. Move on, play another game. If you were playing for $$$, I'd have a different view.

@grogers then why lichess use anticheat system ?
Every match will be a fair play.
If lichess not improve their system on running time then in future players will leave to play here.
then only title players & engine users will play here.

lichess making a reasonable effort to detect cheaters is completely different than the players worrying so much about it.