refactor: delete the compatibility config surface

packages/styles/src/compatibility.ts

@@ -1,59 +0,0 @@
-export const CURRENT_COMPATIBILITY_DATE = "2026-08-02";
-export const CURRENT_FRAMEWORK_BEHAVIOUR = 1;
-
-export interface CompatibilityPolicy {
-  compatibilityDate?: string;
-  frameworkBehaviour?: number;
-}
-
-export interface CompatibilityReport {
-  configuredDate?: string;
-  effectiveDate: string;
-  currentDate: string;
-  configuredBehaviour?: number;
-  effectiveBehaviour: number;
-  currentBehaviour: number;
-  needsUpgrade: boolean;
-  future: boolean;
-  messages: string[];
-}
-
-export function isCompatibilityDate(value: string): boolean {
-  if (!/^\d{4}-\d{2}-\d{2}$/.test(value)) return false;
-  const date = new Date(`${value}T00:00:00.000Z`);
-  return Number.isFinite(date.getTime()) && date.toISOString().slice(0, 10) === value;
-}
-
-export function resolveCompatibility(policy: CompatibilityPolicy): CompatibilityReport {
-  const configuredDate = policy.compatibilityDate;
-  const configuredBehaviour = policy.frameworkBehaviour;
-  const effectiveDate = configuredDate ?? "1970-01-01";
-  const effectiveBehaviour = configuredBehaviour ?? 0;
-  const future =
-    (configuredDate !== undefined && configuredDate > CURRENT_COMPATIBILITY_DATE) ||
-    (configuredBehaviour !== undefined && configuredBehaviour > CURRENT_FRAMEWORK_BEHAVIOUR);
-  const needsUpgrade =
-    !future &&
-    (effectiveDate < CURRENT_COMPATIBILITY_DATE ||
-      effectiveBehaviour < CURRENT_FRAMEWORK_BEHAVIOUR);
-  const messages: string[] = [];
-  if (!configuredDate) messages.push("compatibilityDate is not configured; legacy defaults apply.");
-  if (!configuredBehaviour)
-    messages.push("frameworkBehaviour is not configured; behaviour version 0 applies.");
-  if (future)
-    messages.push("Configuration targets framework behavior newer than this CLI supports.");
-  else if (needsUpgrade)
-    messages.push("A newer compatibility policy is available; review it before upgrading.");
-  else messages.push("Compatibility policy matches the current framework behavior.");
-  return {
-    configuredDate,
-    effectiveDate,
-    currentDate: CURRENT_COMPATIBILITY_DATE,
-    configuredBehaviour,
-    effectiveBehaviour,
-    currentBehaviour: CURRENT_FRAMEWORK_BEHAVIOUR,
-    needsUpgrade,
-    future,
-    messages,
-  };
-}

packages/styles/src/config.ts

@@ -17,11 +17,6 @@ import type { StorageConfig } from "@wrnexus/uploader";
 import type { BrowserCookiesConfig, ThemeConfig } from "./theme.ts";
 import type { FontConfig } from "./fonts.ts";
 import { fontCspSources } from "./fonts.ts";
-import {
-  isCompatibilityDate,
-  resolveCompatibility,
-  type CompatibilityPolicy,
-} from "./compatibility.ts";
 
 export type Mode = "development" | "production";
 
@@ -230,23 +225,12 @@ export interface TypesConfig {
   globalTypes?: string;
 }
 
-export interface FunctionsConfig {
-  legacyDefaultRuntime?: "current" | "client" | "server" | "shared";
-}
-
 export interface StoresConfig {
   strictMutations?: boolean;
   persistence?: boolean;
 }
 
-export interface CompatibilityConfig {
-  legacyEmit?: boolean;
-  legacyEventProps?: boolean;
-  legacyComponentDiscovery?: boolean;
-  stringLayouts?: boolean;
-}
-
-export interface AppConfig extends CompatibilityPolicy {
+export interface AppConfig {
   /** Ordered reusable configuration layers; the application always has final precedence. */
   extends?: string | string[];
   /** Compiler/dev/build plugins, resolved in deterministic pre/normal/post order. */
@@ -260,12 +244,8 @@ export interface AppConfig extends CompatibilityPolicy {
   imports?: ImportsConfig;
   /** TypeScript-backed .wrn type checking and declaration generation. */
   types?: TypesConfig;
-  /** Legacy function runtime behavior for existing applications. */
-  functions?: FunctionsConfig;
   /** Typed global/page store behavior. */
   stores?: StoresConfig;
-  /** Temporary v0.5 syntax compatibility switches. */
-  compatibility?: CompatibilityConfig;
   /** Opt-in APIs that are not yet covered by stable compatibility guarantees. */
   experimental?: ExperimentalConfig;
   /** Route and asset budgets plus build analyzer behavior. */
@@ -597,32 +577,23 @@ export function defineConfig(config: AppConfig): AppConfig {
   return config;
 }
 
+const REMOVED_CONFIG_KEYS = [
+  "compatibilityDate",
+  "frameworkBehaviour",
+  "functions",
+  "compatibility",
+] as const;
+
 export function validateAppConfig(config: AppConfig): ConfigIssue[] {
   const issues: ConfigIssue[] = [];
-  if (config.compatibilityDate !== undefined && !isCompatibilityDate(config.compatibilityDate)) {
-    issues.push({
-      path: "compatibilityDate",
-      severity: "error",
-      message: "must be a real ISO calendar date in YYYY-MM-DD format",
-    });
-  }
-  if (
-    config.frameworkBehaviour !== undefined &&
-    (!Number.isInteger(config.frameworkBehaviour) || config.frameworkBehaviour < 1)
-  ) {
-    issues.push({
-      path: "frameworkBehaviour",
-      severity: "error",
-      message: "must be a positive integer",
-    });
-  }
-  const compatibility = resolveCompatibility(config);
-  if (compatibility.future) {
-    issues.push({
-      path: "compatibilityDate",
-      severity: "error",
-      message: "targets framework behavior newer than this version supports",
-    });
+  for (const key of REMOVED_CONFIG_KEYS) {
+    if ((config as Record<string, unknown>)[key] !== undefined) {
+      issues.push({
+        path: key,
+        severity: "error",
+        message: "was removed; delete it from the configuration",
+      });
+    }
   }
   const sampleRate = config.observability?.sampleRate;
   if (

packages/styles/src/index.ts

@@ -36,13 +36,6 @@ export {
   resolveConfigLayers,
   validateAppConfig,
 } from "./config.ts";
-export {
-  CURRENT_COMPATIBILITY_DATE,
-  CURRENT_FRAMEWORK_BEHAVIOUR,
-  isCompatibilityDate,
-  resolveCompatibility,
-} from "./compatibility.ts";
-export type { CompatibilityPolicy, CompatibilityReport } from "./compatibility.ts";
 export { findStyleEntry, bundleCss } from "./styles.ts";
 export type { FontConfig, GoogleFont, LocalFontFace, FontDisplay } from "./fonts.ts";
 export { renderFontHead, renderProductionFontHead, fontCspSources } from "./fonts.ts";

packages/styles/test/config.test.ts

@@ -7,7 +7,6 @@ import {
   resolveProfile,
   loadEnv,
   renderStyles,
-  resolveCompatibility,
   validateAppConfig,
   explainAppConfig,
 } from "../src/index.ts";
@@ -16,18 +15,6 @@ afterEach(() => {
   delete process.env.WRNEXUS_PROFILE;
 });
 
-test("compatibility dates pin behavior and reject invalid or future policies", () => {
-  expect(
-    resolveCompatibility({ compatibilityDate: "2026-08-02", frameworkBehaviour: 1 }),
-  ).toMatchObject({ needsUpgrade: false, future: false, effectiveBehaviour: 1 });
-  expect(validateAppConfig({ compatibilityDate: "2026-02-31" })).toContainEqual(
-    expect.objectContaining({ path: "compatibilityDate", severity: "error" }),
-  );
-  expect(validateAppConfig({ frameworkBehaviour: 2 })).toContainEqual(
-    expect.objectContaining({ severity: "error" }),
-  );
-});
-
 test("observability config requires bounded sampling and a valid OTLP endpoint", () => {
   expect(validateAppConfig({ observability: { sampleRate: Number.NaN } })).toContainEqual(
     expect.objectContaining({ path: "observability.sampleRate", severity: "error" }),

packages/styles/test/removed-config-keys.test.ts

@@ -0,0 +1,28 @@
+import { expect, test } from "bun:test";
+import { validateAppConfig } from "../src/config.ts";
+
+// A stale config must fail loudly. Silently ignoring a removed key leaves
+// someone believing a flag still applies.
+const REMOVED = [
+  { key: "compatibilityDate", config: { compatibilityDate: "2026-08-02" } },
+  { key: "frameworkBehaviour", config: { frameworkBehaviour: 1 } },
+  { key: "functions", config: { functions: { legacyDefaultRuntime: "current" } } },
+  { key: "compatibility", config: { compatibility: { legacyEmit: false } } },
+];
+
+for (const { key, config } of REMOVED) {
+  test(`a config still setting "${key}" is rejected with a message naming it`, () => {
+    const issues = validateAppConfig(config as never);
+    const match = issues.find((issue) => issue.path === key || issue.path.startsWith(`${key}.`));
+
+    expect(match).toBeDefined();
+    expect(match!.severity).toBe("error");
+    expect(match!.message.toLowerCase()).toContain("removed");
+  });
+}
+
+test("a config without those keys is accepted", () => {
+  const issues = validateAppConfig({} as never);
+
+  expect(issues.filter((issue) => issue.severity === "error")).toEqual([]);
+});