diff --git a/src/jiggle.js b/src/jiggle.js
index de46cff..04231fe 100644
--- a/src/jiggle.js
+++ b/src/jiggle.js
@@ -1,3 +1,9 @@
-export default function() {
-  return (Math.random() - 0.5) * 1e-6;
+// https://en.wikipedia.org/wiki/Linear_congruential_generator#Parameters_in_common_use
+const a = 1664525,
+      c = 1013904223,
+      m = 4294967296;
+let s = 1;
+export default function(seed) {
+  if (seed) s = Math.abs(a * seed);
+  return ((s = (a * s + c) % m) / m - 0.5) * 1e-6;
 }