I noticed you get a 256-trie with: T:{$[~#y;z;@[256#x;*y;:;.z.s[x@*y;1_y;z]]]} that t:T[t;"key";leaf] can be used to store a leaf in the trie, and t@/"key

I noticed you get a 256-trie with: T:{$[~#y;z;@[256#x;*y;:;.z.s[x@*y;1_y;z]]]} that t:T[t;"key";leaf] can be used to store a leaf in the trie, and t@/"key" can be used to look up the key in the trie. Unfortunately, at least on my 1.7Ghz i7, with 8-byte keys, bin remains faster until around 1m records, and the difference remains negligible until you have more like 10m records. By all means, get in touch. I'm always interested in hearing about better things to work on.