I noticed you get a 256-trie with:<p><pre><code>    T:{$[~#y;z;@[256#x;*y;:;.z.s[x@*y;1_y;z]]]}
</code></pre>
that t:T[t;&quot;key&quot;;leaf] can be used to store a leaf in the trie, and t@&#x2F;&quot;key&quot; can be used to look up the key in the trie.<p>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.<p>By all means, get in touch. I&#x27;m always interested in hearing about better things to work on.