[strenholme]

For people who are interested, here is the solution. In standard PGN, the solution is:

1. e4 e5 2. Nf3 Nf6 3. Nxe5 Nxe4 4. Qe2 Nxd2 5. Nc6+ Ne4 6. Nxd8 Kxd8 7. Qxe4 a6 8. Bg5+ Be7 9. Qxe7#

In the Stockfish notation this engine uses, White’s moves are:

1. e2e4 2. g1f3 3. f3e5 4. d1e2 5. e5c6 6. c6d8 7. e2e4 8. c1g5 9. e4e7

Here is a Lichess analysis of this game:

https://lichess.org/WnMF3LpX

(In terms of Regexes, Javascript has a very rich Turing complete Regex library; it’s an open question whether Lua 5.1’s regexes are Turing complete, but they are good enough for the text processing I do)

[zzazzdsa]

I won with 1. e4 e5 2. Qh5 a6 3.Bc4 a5 4. Qxf7#. I wonder if you could implement a stronger engine in regex (stockfish classic at O(1) nodes is plenty strong already)

[wavemode]

I won faster than that:

1.d4 d5 2.c4 dxc4 3.Nc3 Qxd4 4.Qxd4 a6 5.Bf4 a5 6.Bxc7 a4 7.Qd8#