Depends if you have model or not, basically:

DB::table('entries')->groupBy('post_id')->get(['post_id', DB::raw('MAX(id) as id')]);

Thanks for your reply. Would it also be possible to do this without DB::raw?

It's hard to see the benefits of the query builder compared to normal PDO queries if I got to use raw SQL anyway.

->select('MAX(id) AS id');

This might work.

Actually most times you will have problems to order it right. Only way i find that results well is:

$query = Stock::where('account_id', $account_id);

$sub = Stock::orderBy('microtime', 'desc'); #THIS IS MY ORDER FIELD. YOU CAN USE ID IF ITS OK FOR YOU IN MY CASE NOT

 $query->from(DB::raw("({$sub->toSql()}) as sub"))
            ->where('data_movimento','<=', $data_movimento)
            ->whereIn('product_id', $products)
            ->with('product','launch','armazem')
            ->groupBy('armazem_id')->get();

Its a query with a subquery. I try a lot of diferent aprouchs none work.

thank you @zaalbarxx, your answer still helped someone after three years. thumbs up!