The generator matrix

 1  0  0  1  1  X  1  0  1  1  X  0  1  1  X
 0  1  0  1  0  0 X+1  1  X  1  1  X  X X+1  1
 0  0  1  1  X  1  1  X  X X+1  X  1  0 X+1  0

generates a code of length 15 over Z2[X]/(X^2) who´s minimum homogenous weight is 14.

Homogenous weight enumerator: w(x)=1x^0+15x^14+32x^15+15x^16+1x^30

The gray image is a linear code over GF(2) with n=30, k=6 and d=14.
As d=14 is an upper bound for linear (30,6,2)-codes, this code is optimal over Z2[X]/(X^2) for dimension 6.
This code was found by Heurico 1.16 in 0.176 seconds.