Add the Analysing the UK Autumn Budget 2026 webinar deck

lib/slideshows.ts

@@ -29,8 +29,10 @@ import { overhang2026LightningConfig } from "@/slideshows/overhang-2026-lightnin
 import { blsTaxsim2026Config } from "@/slideshows/bls-taxsim-2026/config";
 import { scottishGovernment2026Config } from "@/slideshows/scottish-government-2026/config";
 import { goodGrowthFoundation2026Config } from "@/slideshows/good-growth-foundation-2026/config";
+import { autumnBudget2026Config } from "@/slideshows/autumn-budget-2026/config";
 
 export const slideshows: SlideshowConfig[] = [
+  autumnBudget2026Config,
   goodGrowthFoundation2026Config,
   scottishGovernment2026Config,
   blsTaxsim2026Config,

next.config.ts

@@ -8,6 +8,16 @@ const nextConfig: NextConfig = {
   env: {
     NEXT_PUBLIC_BASE_PATH: '/slides',
   },
+  // The Autumn Budget 2026 webinar deck was introduction-2026 until 28 October.
+  async redirects() {
+    return [
+      {
+        source: '/introduction-2026/:path*',
+        destination: '/autumn-budget-2026/:path*',
+        permanent: true,
+      },
+    ];
+  },
   // Pin the workspace root so Turbopack does not silently pick up a stray
   // lockfile from a parent directory during local development or CI.
   turbopack: {

slideshows/autumn-budget-2026/README.md

@@ -0,0 +1,33 @@
+# Analysing the Autumn Budget 2026 with PolicyEngine
+
+5 slides at `/slides/autumn-budget-2026`, for the 28 October 2026 webinar
+(`/slides/introduction-2026` redirects here):
+what PolicyEngine is, how we prepared for Budget day, and a slide with the live
+[Autumn Budget 2026 dashboard](https://ab2026-local-preview.vercel.app/uk/autumn-budget-2026)
+embedded in it, where the analysis is presented. The closing slide links the
+same address, with its QR code, and credits the Nuffield Foundation, which
+funds our UK Budget analysis.
+
+- `config.ts` controls the slide order and metadata.
+- `content.ts` holds the sources, the three pillars of What PolicyEngine is,
+  the dates of the Budget-day rehearsals (the mock Budgets) and the
+  preparation items, written for a general audience.
+- `slides/index.tsx` contains the slides. The analysis slide embeds the
+  dashboard itself (`slides/DashboardEmbed.tsx`): Expand stretches the same
+  frame over the whole screen, so whatever is open in it is kept, and New tab
+  opens it in the browser. Buttons in its bar load the Public finances,
+  Pensioners (By age) and Living standards sub-tabs and the Household
+  calculator tab into the frame. The deck draws no charts of its own, so nothing
+  here goes stale when the dashboard's data change.
+- `SPEAKER-NOTES.md` gives the presenter track.
+
+`public/images/autumn-budget-2026/dashboard-qr.svg` encodes
+the dashboard's address.
+
+`public/logos/funders/nuffield-foundation-white.svg` is the Nuffield
+Foundation's white logo, downloaded from nuffieldfoundation.org on 22 October
+2026 (3,432 bytes, SHA-256
+`b3727385be9295f8daa3938c745f87b2e00e5675130354f6394ae6b3fec5654c`). That day
+its communications team asked for "funded" rather than "supported", and for
+its logo, the white version on a dark background. Keep the file as
+downloaded; don't recolour or redraw it.

slideshows/autumn-budget-2026/SPEAKER-NOTES.md

@@ -0,0 +1,70 @@
+# Speaker notes: Analysing the UK Autumn Budget 2026 with PolicyEngine
+
+## 1. Title
+
+Webinar, Wednesday 28 October 2026, 4:30pm UK time. Presenters: Vahid
+Ahmadi, Max Ghenis, María Juaristi.
+
+## 2. What PolicyEngine is
+
+A brief view: PolicyEngine in one line (a nonprofit building free,
+open-source tools, in policyengine.org's own words), then the rules, the
+households and the results, and that all the code is public.
+
+## 3. How we prepared
+
+The slide is for a general audience: the rehearsals and what they gave us.
+The detail below is background, if asked.
+
+- Last year's Budget (26 November 2025): the dashboard went live on Budget
+  day, and the other measures and the household calculator followed by 28
+  November (the 2025 dashboard repo's commit history).
+- Five Budget-day rehearsals, the mock Budgets (28 September; 5, 12, 19 and
+  26 October): drill issues #6 (with the drill 1 retrospective), #8, #10, #53
+  and #144 in the dashboard repo.
+- The model and data: the policyengine package 6.11.1, with policyengine-uk
+  2.151.0 and the Microcosm UK 2024-25 households. The live dashboard's
+  publication manifest records it for every measure and the package, and
+  main's uv.lock pins it (28 October).
+- National results run on Modal, one machine per measure: all ten units (nine
+  measures and the package) took 8.1 minutes on 26 October (dashboard PR
+  #178). The household calculator also runs on Modal and is kept warm.
+- Mark anything still in review as such on the slide before presenting.
+
+## 4. The analysis: live dashboard
+
+The dashboard itself is on the slide; it loads while slide 3 is showing.
+Press **Expand** to fill the screen with it and present from there. **Back to
+the slide** returns to the deck with the same tab, measures and household
+still open. **New tab** opens it in a browser tab, if the embedded copy ever
+misbehaves.
+
+While you are using the dashboard, the arrow keys, Space and a clicker go to
+it, not to the deck (the arrows switch its tabs). Press **Back to the slide**,
+or click the bar above the dashboard, before moving on.
+
+The buttons in the bar (Public finances, Pensioners, Living standards,
+Household calculator) load that view into the frame; each click reloads it,
+so measures or a household chosen in the frame are not kept. Its tabs:
+
+- **Population impact**, with five sub-tabs: **Public finances** (the
+  default: revenue by year and the OBR comparison), **All households** (the
+  constituency map and households by income), **By age** (the Pensioners
+  button opens it at pensioners), **Living standards** (income by decile and
+  inequality) and **Poverty**.
+- **Household calculator**: run one household live with Calculate, or pick
+  an example card.
+- **Pre-measures forecast**: the outlook before the Budget's measures, with
+  the OBR forecast named on the tab.
+- **Policies**: what each measure does.
+- **Methodology**.
+
+These are the tabs at ab2026-local-preview.vercel.app/uk/autumn-budget-2026
+on 28 October. The frame and the closing slide's link and QR code all open
+that address.
+
+## 5. Close
+
+The dashboard link, with a QR code for phones, and how to reach us. Thank
+the Nuffield Foundation, which funds our UK Budget analysis ("funded by",
+not "supported by").

slideshows/autumn-budget-2026/config.ts

@@ -0,0 +1,26 @@
+import type { SlideshowConfig } from "@/lib/types";
+import {
+  ClosingSlide,
+  DashboardSlide,
+  PreparationSlide,
+  TitleSlide,
+  WhatSlide,
+} from "./slides";
+
+export const autumnBudget2026Config: SlideshowConfig = {
+  id: "autumn-budget-2026",
+  title: "Analysing the Autumn Budget 2026 with PolicyEngine",
+  description:
+    "What PolicyEngine is, how we prepared for Budget day, and the analysis, presented live on the dashboard.",
+  date: "2026-10-28",
+  location: "PolicyEngine",
+  // The slides keep this clear of the viewer's slide counter (deck.module.css).
+  footerText: "Autumn Budget 2026 webinar · 28 October 2026",
+  slides: [
+    TitleSlide,
+    WhatSlide,
+    PreparationSlide,
+    DashboardSlide,
+    ClosingSlide,
+  ],
+};

slideshows/autumn-budget-2026/content.ts

@@ -0,0 +1,144 @@
+// Content for the PolicyEngine and Autumn Budget 2026 deck.
+
+export type Source = { label: string; href: string };
+
+export const sources = {
+  home: { label: "policyengine.org", href: "https://www.policyengine.org/uk" },
+  model: {
+    label: "PolicyEngine UK code",
+    href: "https://github.com/PolicyEngine/policyengine-uk",
+  },
+  data: {
+    label: "Microcosm data pipeline",
+    href: "https://github.com/PolicyEngine/microcosm",
+  },
+  hansard: {
+    label: "Hansard, 24 February 2026",
+    href: "https://hansard.parliament.uk/Lords/2026-02-24/debates/A381F7D6-0A3C-48FD-8D9E-67751E25877A/NationalInsuranceContributions(EmployerPensionsContributions)Bill",
+  },
+  tpa: {
+    label: "Tax Policy Associates, September 2026",
+    href: "https://taxpolicy.org.uk/2026/09/10/universities-uk-national-insurance-proposal/",
+  },
+  cps: {
+    label: "Centre for Policy Studies, July 2023",
+    href: "https://cps.org.uk/research/family-friendly-taxation/",
+  },
+  nuffield: {
+    label: "Nuffield Foundation project",
+    href: "https://www.nuffieldfoundation.org/project/enhancing-localising-and-democratising-tax-benefit-policy-analysis",
+  },
+  nef: {
+    label: "New Economics Foundation, July 2026",
+    href: "https://neweconomics.org/2026/07/insecure-low-quality-work-a-major-driver-of-uks-neets-and-inactivity-crisis",
+  },
+  no10Post: {
+    label: "PolicyEngine at No 10",
+    href: "https://www.policyengine.org/uk/research/policyengine-10-downing-street",
+  },
+  // The dashboard the webinar presents, on the analysis slide and in the
+  // closing slide's link and QR code. The host alone returns 404.
+  dashboard: {
+    label: "Autumn Budget 2026 dashboard",
+    href: "https://ab2026-local-preview.vercel.app/uk/autumn-budget-2026",
+  },
+  dashboardCode: {
+    label: "Dashboard code",
+    href: "https://github.com/PolicyEngine/uk-autumn-budget-dashboard-2026",
+  },
+  dashboard2025Code: {
+    label: "2025 dashboard code",
+    href: "https://github.com/PolicyEngine/uk-autumn-budget-dashboard",
+  },
+};
+
+// How policyengine.org/uk/donate describes PolicyEngine.
+export const about =
+  "PolicyEngine is a nonprofit building free, open-source tools that help people understand tax and benefit policies.";
+
+// The Nuffield Foundation's credit. On 22 October its communications team
+// asked for "funded" rather than "supported", and for its logo, the white
+// version on a dark background. The logo is the white one from
+// nuffieldfoundation.org, kept as downloaded (3,432 bytes, SHA-256
+// b3727385…); its own size is 117.862 by 70.
+export const funder = {
+  label: "Funded by",
+  name: "Nuffield Foundation",
+  logo: "/logos/funders/nuffield-foundation-white.svg",
+  width: 118,
+  height: 70,
+};
+
+// What PolicyEngine is: the rules, the households and the results. The rules
+// are the main ones in the Good Growth Foundation deck's checked list.
+export const pillars = [
+  {
+    title: "Rules",
+    items: [
+      "Income tax and National Insurance",
+      "Universal Credit and other benefits",
+      "State Pension and Pension Credit",
+      "VAT, fuel duty and capital gains tax",
+    ],
+  },
+  {
+    title: "Households",
+    items: [
+      "Built from the Family Resources Survey",
+      "With HMRC tax records and other surveys",
+      "Weighted to match official statistics",
+      "Or enter any household yourself",
+    ],
+  },
+  {
+    title: "Results",
+    items: [
+      "Cost or saving to the Treasury",
+      "Who gains and loses, by income decile",
+      "Poverty and inequality",
+      "By region and constituency",
+    ],
+  },
+];
+
+// Last year's Budget, from the 2025 dashboard's commit history: the dashboard
+// went live on the day, and the other measures and the household calculator
+// followed by 28 November.
+export const lastBudget = {
+  title: "Autumn Budget 2025",
+  text: "Analysed on the day, 26 Nov",
+};
+
+// The five Budget-day rehearsals (the mock Budgets): full runs of the day on
+// invented measures.
+export const mockBudgets = ["28 Sep", "5 Oct", "12 Oct", "19 Oct", "26 Oct"];
+
+export type PrepItem = { title: string; text: string; status: "Done" | "In review" };
+
+// Written for a general audience: the technical detail is in the speaker
+// notes. Each line is checked against PolicyEngine/uk-autumn-budget-dashboard-2026;
+// the version is the one in the live dashboard's publication manifest and in
+// main's uv.lock on 28 October.
+export const preparation: PrepItem[] = [
+  {
+    title: "Fixed model and data",
+    text: "Every figure comes from PolicyEngine 6.11.1 and the same set of households, so anyone can reproduce it.",
+    status: "Done",
+  },
+  {
+    title: "A household calculator",
+    text: "Enter any household to see how the measures change its income, live on the dashboard.",
+    status: "Done",
+  },
+  {
+    title: "Every measure in about 8 minutes",
+    text: "The cost of each measure, and who gains and loses, worked out all at once rather than one by one.",
+    status: "Done",
+  },
+  {
+    title: "Each measure published once reviewed",
+    text: "A measure goes on the dashboard as soon as its figures have been checked.",
+    status: "In review",
+  },
+];
+

slideshows/autumn-budget-2026/funder.test.ts

@@ -0,0 +1,31 @@
+import { createHash } from "node:crypto";
+import { readFileSync } from "node:fs";
+import path from "node:path";
+import { describe, expect, it } from "vitest";
+import { funder } from "./content";
+
+// The white logo as downloaded from nuffieldfoundation.org on 22 October. Keep
+// it byte for byte: don't recolour or redraw it.
+const DOWNLOADED_SHA256 =
+  "b3727385be9295f8daa3938c745f87b2e00e5675130354f6394ae6b3fec5654c";
+
+describe("the Nuffield Foundation credit on the closing slide", () => {
+  const file = path.join(__dirname, "../../public", funder.logo);
+  const bytes = readFileSync(file);
+
+  it("uses the logo exactly as downloaded", () => {
+    expect(bytes.length).toBe(3432);
+    expect(createHash("sha256").update(bytes).digest("hex")).toBe(DOWNLOADED_SHA256);
+  });
+
+  it("matches the logo's own dimensions", () => {
+    const svg = bytes.toString("utf8");
+    const size = (name: string) => Number(svg.match(new RegExp(`${name}="([\\d.]+)"`))?.[1]);
+    expect(Math.round(size("width"))).toBe(funder.width);
+    expect(Math.round(size("height"))).toBe(funder.height);
+  });
+
+  it('reads "Funded by"', () => {
+    expect(funder.label).toBe("Funded by");
+  });
+});