diff --git a/dataflow_neuro/primitives.act b/dataflow_neuro/primitives.act
index 540fa88..624ab34 100644
--- a/dataflow_neuro/primitives.act
+++ b/dataflow_neuro/primitives.act
@@ -165,7 +165,7 @@ namespace tmpl {
             fifo_element[i].supply = supply;
             fifo_element[i].reset_B = _reset_BXX[i];
           )
-          fifo_element[N-1].out = out;
+          fifo_element[M-1].out = out;
 
           // reset buffers
           bool _reset_BX;
@@ -697,6 +697,7 @@ namespace tmpl {
           PULLUP_X4 pull_up(.a=nor_out, .y=out);
         }
 
+        export
         defproc line_end_pull_down (a1of1 in; bool? reset_B; power supply; bool! out)
         {
           bool _out, __out, nor_out;
@@ -707,4 +708,61 @@ namespace tmpl {
 
           PULLUP_X4 pull_down(.a=nor_out, .y=out);
         }
+        
+
+        
+
+        /**
+         * Appends a hard-coded word "VAL" to an input.
+         * Works by piping through all sigs, but adding
+         * some extra sigs when the input is valid.
+         * N is size of channel to pipe through.
+         * NVAL is size of word to be put on output.
+         * VAL is word to be put on output.
+         *
+         */
+        export template<pint N, NVAL, VAL>
+        defproc append (avMx1of2<N> in; avMx1of2<N+NVAL> out; power supply)
+        {
+            { N >= 0 : "What?" };
+            { NVAL >= 0 : "What?" };
+            { NVAL < 1<<VAL : "VAL too big!" };
+
+            // valid tree
+            vtree<N> in_val(.supply = supply);
+            (i:N:
+                in_val.in.d[i].t = in.d.d[i].t;
+                in_val.in.d[i].f = in.d.d[i].f;
+            )
+
+            // wire through most signals
+            (i:N:
+                in.d.d[i].t = out.d.d[i].t;
+                in.d.d[i].f = out.d.d[i].f;
+            )
+            in.a = out.a;
+            in.v = out.v;
+
+            // appender
+            pint bitval;
+            sigbuf<NVAL> sb(.in = in_val.out, .supply = supply);
+            TIELO_X1 tielows[NVAL];
+            (i:NVAL:tielows[i].vss = supply.vss; tielows[i].vdd = supply.vdd;)
+            (i:0..NVAL-1:
+                bitval = (VAL & ( 1 << i )) >> i;
+                [  bitval = 1 ->
+                    out.d.d[i+N].t = sb.out[i];
+                    out.d.d[i+N].f = tielows[i].y;
+                [] bitval = 0 ->
+                    out.d.d[i+N].f = sb.out[i];
+                    out.d.d[i+N].t = tielows[i].y;
+                [] bitval >= 2 -> {false : "fuck"};        
+                ]
+            )
+
+        }
+
+
+
+
 }}