diff --git a/tile.cc b/tile.cc
index 7b1931b..5c5adf9 100644
--- a/tile.cc
+++ b/tile.cc
@@ -197,6 +197,39 @@ int remove_noop(struct draw *geom, int n) {
 	return out;
 }
 
+int shrink_lines(struct draw *geom, int len, int z, int basezoom) {
+	double scale = 1.0 / exp(log(sqrt(2.5)) * (basezoom - z));
+	struct draw tmp[3 * len];
+	int out = 0;
+	int i;
+
+	for (i = 0; i < len; i++) {
+		if (i > 0 && (geom[i - 1].op == VT_MOVETO || geom[i - 1].op == VT_LINETO) && geom[i].op == VT_LINETO) {
+			long long cx = (geom[i].x + geom[i - 1].x) / 2;
+			long long cy = (geom[i].y + geom[i - 1].y) / 2;
+
+			tmp[out + 0].op = VT_MOVETO;
+			tmp[out + 0].x = cx + (geom[i - 1].x - cx) * scale;
+			tmp[out + 0].y = cy + (geom[i - 1].y - cy) * scale;
+
+			tmp[out + 1].op = VT_LINETO;
+			tmp[out + 1].x = cx + (geom[i].x - cx) * scale;
+			tmp[out + 1].y = cy + (geom[i].y - cy) * scale;
+
+			tmp[out + 2].op = VT_MOVETO;
+			tmp[out + 2].x = geom[i].x;
+			tmp[out + 2].y = geom[i].y;
+
+			out += 3;
+		} else {
+			tmp[out++] = geom[i];
+		}
+	}
+
+	memcpy(geom, tmp, out * sizeof(struct draw));
+	return out;
+}
+
 void to_tile_scale(struct draw *geom, int n, int z, int detail) {
 	int i;
 
@@ -261,12 +294,16 @@ long long write_tile(struct index *start, struct index *end, char *metabase, uns
 		}
 
 		int len = decode_feature(&meta, NULL, z, tx, ty, detail);
-		struct draw geom[len];
+		struct draw geom[3 * len];
 
 		meta = metabase + i->fpos;
 		deserialize_int(&meta, &t);
 		decode_feature(&meta, geom, z, tx, ty, detail);
 
+		if (t == VT_LINE && z != basezoom) {
+			len = shrink_lines(geom, len, z, basezoom);
+		}
+
 		to_tile_scale(geom, len, z, detail);
 
 		if (t == VT_LINE || t == VT_POLYGON) {