The realization space is
  [1   1   0   x1   1   0   0       x1    1       x1]
  [0   1   1   -1   1   1   0   x1 - 1    0   x1 - 1]
  [0   0   0    0   1   1   1       x1   x1     x1^2]
in the multivariate polynomial ring in 1 variable over ZZ
avoiding the zero loci of the polynomials
RingElem[x1, x1 - 1, x1^2 - x1 + 1, x1^2 + 1, x1 + 1, x1^2 + x1 - 1]