diff --git a/bct.k b/bct.k
new file mode 100644
index 0000000..05b709e
--- /dev/null
+++ b/bct.k
@@ -0,0 +1,14 @@
+/ Bitwise Cyclic Tag (https://esolangs.org/wiki/Bitwise_Cyclic_Tag)
+/ 
+/ 00111
+/ 101
+i:0
+c:-1_(1:`)-"0"
+d:-1_(1:`)-"0"
+bct:{[d;c;i]
+ \(d;c[(#c)!i+!c[i]+1])
+ e:c@i
+ n:(#c)!i+1
+ ((~e)_d,(c[i]**d)#c@n;c;(#c)!n+e)}.
+cond: {[d;c;i] 0<(#d)&#c}.
+cond bct/(d;c;i);