Thanks for the challenge, Geronimoo. And as I said in my submission, it was extremely convenient that you ran this the same week as def's "no buys" because as soon as I had completed my submission for that challenge, I realized I could use the same basic approach here.
Here we had to start with a treasure map opening which was really annoying for getting the opening right. Opening chapel/treasure map, I realized after a few attempts that in order to get what would probably be the best result I would need to buy a highway as soon as possible (because ironworks -> village -> bridge is too slow when we have to carry around a worthless treasure map) so even though the opening split of 5/2 or 4/3 wouldn't matter, I had to restart until I got 5 coppers on either turn 3 or turn 4, and could trash at least two estates and another card on the other turn. However like with def's challenge, once I got the correct opening, the rest was pretty smooth sailing.
My turn 10 in this challenge is remarkably similar to my turn 9 in def's naturally. I was actually foolish and the first time I got to a turn 10 with everything set up correctly I just blazed through it incorrectly assuming that my experience from the previous challenge would allow me to intuitively gain things in the right proportions to complete the challenge. I was wrong. I ran out of ironworks and I hadn't put in workshops into the kingdom so I ran out of gains. Whoops. I restarted, putting in workshops, and the next time I got the correct opening I realized I accidentally had bought an ironworks instead of a treasure map on my opening buy. I played it out, gaining a treasure map with the ironworks on the first available opportunity, and I got the 10 turn solution and I was half considering just submitting it. But I figured if I could get to that point twice I could do it again, so a few more restart attempts and I got it. And somehow after mapping out my gains for turn 10 I realized I wouldn't need the workshops at all, but if I got them I could gain a few bridges just for fun, so I did.