In these situations we should be able to quickly find mate by incentivizing pushing the enemy king to the edge of the board.
(venv) dave@zwingli ra-chess-engine % go build && ./ra-chess-engine --tactics --epd test-suites/basic.epd -tacticsthinkingtime 5000 -epdregex testGuard
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...K.Pk.
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8/8/3K1Pk1/8/8/8/8/8 w - - 0 1
1 0 0 5 Kc5
1 210 0 11 Ke5
2 210 0 27 Ke5 Kg5
3 210 0 113 Ke5 Kf7 Kf5
3 220 0 249 Ke6 Kg5 f7 Kf4
4 230 0 429 Ke6 Kh6 Kf5 Kh5
4 1190 0 517 Ke7 Kg5 f7 Kf4 f8=Q Ke3
5 1190 0 850 Ke7 Kg5 f7 Kf4 f8=Q Ke3
6 1200 0 2105 Ke7 Kg5 f7 Kf4 f8=Q Ke3 Kd6 Kd3
7 1200 0 4680 Ke7 Kg5 f7 Kf4 f8=Q Ke3 Kd6 Kd3
8 1200 0 11982 Ke7 Kg5 f7 Kf4 f8=Q Ke3 Kd6 Kd3 Kc5 Kc3
9 1200 0 26056 Ke7 Kg5 f7 Kf4 f8=Q Ke3 Kd6 Kd3 Kc5 Kc3
10 1200 0 50692 Ke7 Kg5 f7 Kf4 f8=Q Ke3 Kd6 Kd3 Kc5 Ke3 Kc4 Ke4
11 1200 0 71128 Ke7 Kg5 f7 Kf4 f8=Q Ke3 Kd6 Kd3 Ke5 Kc3 Qc5 Kb2 Qc4
11 1210 0 82226 Ke6 Kh6 f7 Kg7 Ke7 Kg6 f8=Q Kg5 Kd6 Kg4 Kc5 Kg3
12 1210 0 107827 Ke6 Kh6 f7 Kg7 Ke7 Kg6 f8=Q Kg5 Kd6 Kg4
13 1210 0 310424 Ke6 Kh6 f7 Kg7 Ke7 Kg6 f8=Q Kg5 Kd6 Kg4 Kc5 Kg3 Kc4 Kg2
14 1210 6 595411 Ke6 Kh6 f7 Kg7 Ke7 Kg6 f8=Q Kg5 Kd6 Kg4 Kc5 Kg3 Kc4 Kg2
15 1230 6 1597498 Ke6 Kh6 f7 Kg7 Ke7 Kg6 f8=Q Kg5 Qf3 Kg6 Qg4 Kh6 Qf5 Kg7 Qg5 Kh7 Kd6 Kh8
16 1230 26 2781959 Ke6 Kh6 f7 Kg7 Ke7 Kg6 f8=Q Kg5 Qf3 Kh4 Qg2
17 1230 18 4462667 Ke6 Kh6 f7 Kg7 Ke7 Kg6 f8=Q Kg5 Qf3 Kh4 Qg2 Kh5 Kd6 Kh4 Kd5 Kh5 Qg1 Kh4
18 1230 56 6600722 Ke6 Kh6 f7 Kg7 Ke7 Kg6 f8=Q Kg5 Qf3 Kh4 Qg2 Kh5 Kd6 Kh4 Kd5
18 Mate8 285 10745165 Ke7 Kg5 f7 Kf4 f8=Q Ke3 Kd6 Kd3 Kd5 Kc3 Qg7 Kb3 Kc5 Ka2 Kc4 Ka3 Qa1#
[testGuard - OK] expected=Ke5 Ke6 Ke7 move=Ke7 result=d6e7 (time=2.859346062s, value=Mate(8), depth=18, stats=[nodes=10745390, leafnodes=3840000, branchnodes=5143101, qbranchnodes=1762289, tthits=13940505, cutoffs=1500760, hash cutoffs=1214966, null cutoffs=2920214, killer cutoffs={1: 148729, 2: 22195}, qcutoffs=32, qcapturesfiltered=0], pv=Ke7 Kg5 f7 Kf4 f8=Q Ke3 Kd6 Kd3 Kd5 Kc3 Qg7 Kb3 Kc5 Ka2 Kc4 Ka3 Qa1#)
Complete. 1/1 positions correct (100.00%)
Final stats [nodes=10745390, leafnodes=3840000, branchnodes=5143101, qbranchnodes=1762289, tthits=13940505, cutoffs=1500760, hash cutoffs=1214966, null cutoffs=2920214, killer cutoffs={1: 148729, 2: 22195}, qcutoffs=32, qcapturesfiltered=0]%
Takes 4 seconds on my macbook now, really this should be findable very quickly.