CVXPY
Minimize
  Sum(abs(X + Y), None, False)
Subject To
Bounds
 0.0 <= X
 0.0 <= Y
End
----------------------------------------
AFTER COMPILATION
Minimize
 Obj: +1 x_0 +1 x_1
Subject to
 c1: -1 x_2 <= +0
 c2: -1 x_3 <= +0
 c3: -1 x_4 <= +0
 c4: -1 x_5 <= +0
 c5: -1 x_0 +1 x_2 +1 x_4 <= +0
 c6: -1 x_1 +1 x_3 +1 x_5 <= +0
 c7: -1 x_0 -1 x_2 -1 x_4 <= +0
 c8: -1 x_1 -1 x_3 -1 x_5 <= +0
Bounds
 x_0 free
 x_1 free
 x_2 free
 x_3 free
 x_4 free
 x_5 free
End
----------------------------------------
SCIP
Minimize
 Obj: +1 x5
Subject to
\   [nonlinear] <c1>: abs((<X_0>+<Y_0>))+abs((<X_1>+<Y_1>))+<x5>*(-1) <= 0;
Bounds
 x5 free
End