diff --git a/src/qft/carpet.js b/src/qft/carpet.js
index cccddac..544d68b 100644
--- a/src/qft/carpet.js
+++ b/src/qft/carpet.js
@@ -43,6 +43,13 @@ export function carpetSVG(size, opts = {}) {
     blips: 1.0,             // density of the spiralling wave-packet excitations
     hue: 0.52, hue2: 0.55, sat: 0.55, lightNear: 0.34, lightFar: 0.62,
     strokeNear: 1.7, strokeFar: 0.5,
+    // optional field injections (all default OFF → output unchanged):
+    //   warpFn(t, d)  → extra normalized vertical displacement (×amp) — an
+    //                   external field (e.g. wind) shaping the rows
+    //   phaseFn(t, r) → phase shift added to every base mode (shimmer)
+    //   modesFn(rng, o) → replace the base mode set entirely (e.g. a CMB
+    //                   power-spectrum-shaped spectrum)
+    warpFn: null, phaseFn: null, modesFn: null,
   }, opts);
   const W = size, H = size, u = size / 1000;
   const paper = resolveSubstrate(o.substrate).paper.flat;
@@ -50,8 +57,10 @@ export function carpetSVG(size, opts = {}) {
 
   // ---- base sea: low-frequency field modes (phase drifts slowly per row) ----
   const M = Math.round(4 + o.chaos * 8);
-  const modes = [];
-  for (let m = 0; m < M; m++) {
+  let modes = [];
+  if (o.modesFn) {
+    modes = o.modesFn(rng, o);
+  } else for (let m = 0; m < M; m++) {
     const f = range(rng, 0.4, 3.0 + o.chaos * 5);     // low q: long swells dominate
     modes.push({ f, a: 1 / (1 + f * 1.0), phi: range(rng, 0, Math.PI * 2), drift: range(rng, -1, 1) * (0.06 + f * 0.02) });
   }
@@ -78,7 +87,8 @@ export function carpetSVG(size, opts = {}) {
 
   const value = (t, r) => {
     let s = 0;
-    for (const m of modes) s += m.a * Math.sin(2 * Math.PI * m.f * t + m.phi + r * m.drift);
+    const dphi = o.phaseFn ? o.phaseFn(t, r) : 0;
+    for (const m of modes) s += m.a * Math.sin(2 * Math.PI * m.f * t + m.phi + r * m.drift + dphi);
     s /= norm;
     let blip = 0;
     for (const e of exc) {
@@ -112,7 +122,8 @@ export function carpetSVG(size, opts = {}) {
     for (let i = 0; i <= npts; i++) {
       const t = i / npts;
       const e = env(t);
-      pts.push({ x: cx - half + t * 2 * half, y: baseY[r] - amp * e * value(t, r) - amp * 0.55 * (e - eMin) * d });
+      const warp = o.warpFn ? o.warpFn(t, d) * amp : 0;
+      pts.push({ x: cx - half + t * 2 * half, y: baseY[r] - amp * e * value(t, r) - amp * 0.55 * (e - eMin) * d + warp });
     }
     const path = smoothPath(pts);
     const hue = o.hue + (o.hue2 - o.hue) * (1 - d);