diff --git a/.changeset/node-engine-support.md b/.changeset/node-engine-support.md
new file mode 100644
index 00000000..9bb8af57
--- /dev/null
+++ b/.changeset/node-engine-support.md
@@ -0,0 +1,8 @@
+---
+"@proofkit/cli": patch
+"create-proofkit": patch
+"@proofkit/fmdapi": patch
+"@proofkit/fmodata": patch
+---
+
+Restrict Node engines to 22, 24, or 26.
diff --git a/.changeset/quiet-command-parsing.md b/.changeset/quiet-command-parsing.md
new file mode 100644
index 00000000..157ac389
--- /dev/null
+++ b/.changeset/quiet-command-parsing.md
@@ -0,0 +1,5 @@
+---
+"@proofkit/cli": patch
+---
+
+Parse generated package-manager commands with shell-style quoting.
diff --git a/.github/workflows/check-skills.yml b/.github/workflows/check-skills.yml
index 8faa36da..92574df4 100644
--- a/.github/workflows/check-skills.yml
+++ b/.github/workflows/check-skills.yml
@@ -35,7 +35,7 @@ jobs:
       - name: Setup Node
         uses: actions/setup-node@v4
         with:
-          node-version: 20
+          node-version: 22
 
       - name: Install intent
         run: npm install -g @tanstack/intent
diff --git a/.github/workflows/validate-skills.yml b/.github/workflows/validate-skills.yml
index 8f39716a..61e6eaa5 100644
--- a/.github/workflows/validate-skills.yml
+++ b/.github/workflows/validate-skills.yml
@@ -23,7 +23,7 @@ jobs:
       - name: Setup Node
         uses: actions/setup-node@v4
         with:
-          node-version: 20
+          node-version: 22
 
       - name: Install intent CLI
         run: npm install -g @tanstack/intent
diff --git a/package.json b/package.json
index 2d70a27a..15223cd2 100644
--- a/package.json
+++ b/package.json
@@ -46,7 +46,7 @@
   },
   "packageManager": "pnpm@11.1.1",
   "engines": {
-    "node": ">=18"
+    "node": "^22.0.0 || ^24.0.0 || ^26.0.0"
   },
   "name": "with-changesets",
   "lint-staged": {
diff --git a/packages/cli-old/package.json b/packages/cli-old/package.json
index a9da8d36..468a8075 100644
--- a/packages/cli-old/package.json
+++ b/packages/cli-old/package.json
@@ -35,7 +35,7 @@
     "package.json"
   ],
   "engines": {
-    "node": "^20.0.0 || ^22.0.0"
+    "node": "^22.0.0 || ^24.0.0 || ^26.0.0"
   },
   "scripts": {
     "typecheck": "tsc",
diff --git a/packages/cli/src/cli/init.ts b/packages/cli/src/cli/init.ts
index 0d4ceee4..0e8de6de 100644
--- a/packages/cli/src/cli/init.ts
+++ b/packages/cli/src/cli/init.ts
@@ -4,7 +4,7 @@ import { execa } from "execa";
 import fs from "fs-extra";
 import type { PackageJson } from "type-fest";
 
-import { DEFAULT_APP_NAME } from "~/consts.js";
+import { DEFAULT_APP_NAME, NODE_RUNTIME_VERSION } from "~/consts.js";
 import { createPnpmWorkspaceFileContent } from "~/core/planInit.js";
 import { addAuth } from "~/generators/auth.js";
 import { runCodegenCommand } from "~/generators/fmdapi.js";
@@ -20,9 +20,10 @@ import { buildPkgInstallerMap } from "~/installers/index.js";
 import { initProgramState, isNonInteractiveMode, state } from "~/state.js";
 import { getVersion } from "~/utils/getProofKitVersion.js";
 import { getUserPkgManager } from "~/utils/getUserPkgManager.js";
+import { logger } from "~/utils/logger.js";
 import { parseNameAndPath } from "~/utils/parseNameAndPath.js";
 import { type Settings, setSettings } from "~/utils/parseSettings.js";
-import { formatPackageManagerCommand } from "~/utils/projectFiles.js";
+import { formatPackageManagerCommand, parseCommandString } from "~/utils/projectFiles.js";
 import { validateAppName } from "~/utils/validateAppName.js";
 import { promptForFileMakerDataSource } from "./add/data-source/filemaker.js";
 import { select, text } from "./prompts.js";
@@ -147,8 +148,6 @@ type ProofKitPackageJSON = PackageJson & {
   };
 };
 
-const NODE_RUNTIME_VERSION = "^24.11.0";
-
 const missingTypegenCommandPatterns = [
   /ERR_PNPM_RECURSIVE_EXEC_FIRST_FAIL[\s\S]*Command\s+["'`]typegen["'`]\s+not found/i,
   /Command\s+["'`]typegen["'`]\s+not found/i,
@@ -432,22 +431,34 @@ export const runInit = async (name?: string, opts?: CliFlags) => {
   }
 
   if (!noInstall) {
-    const [fixCommand, ...fixArgs] = formatPackageManagerCommand(pkgManager, "fix").split(" ");
+    const fixCommandString = formatPackageManagerCommand(pkgManager, "fix");
+    const [fixCommand, ...fixArgs] = parseCommandString(fixCommandString);
     if (!fixCommand) {
       throw new Error(`Unable to resolve fix command for ${pkgManager}.`);
     }
     await execa(fixCommand, fixArgs, {
       cwd: projectDir,
       stdio: "pipe",
-    }).catch(() => undefined);
+    }).catch((error: unknown) => {
+      if (state.debug) {
+        logger.warn(`Fix command failed; continuing. packageManager=${pkgManager} command=${fixCommandString}`);
+        logger.error(error);
+      }
+    });
 
-    const [lintCommand, ...lintArgs] = formatPackageManagerCommand(pkgManager, "lint").split(" ");
+    const lintCommandString = formatPackageManagerCommand(pkgManager, "lint");
+    const [lintCommand, ...lintArgs] = parseCommandString(lintCommandString);
     if (!lintCommand) {
       throw new Error(`Unable to resolve lint command for ${pkgManager}.`);
     }
     await execa(lintCommand, lintArgs, {
       cwd: projectDir,
       stdio: "pipe",
+    }).catch((error: unknown) => {
+      logger.warn(`Lint did not succeed; continuing setup. packageManager=${pkgManager} command=${lintCommandString}`);
+      if (state.debug) {
+        logger.error(error);
+      }
     });
   }
 
diff --git a/packages/cli/src/consts.ts b/packages/cli/src/consts.ts
index fe357c5a..251d02ba 100644
--- a/packages/cli/src/consts.ts
+++ b/packages/cli/src/consts.ts
@@ -7,6 +7,7 @@ const distPath = path.dirname(__filename);
 export const PKG_ROOT = process.env.PROOFKIT_PKG_ROOT ?? path.join(distPath, "../");
 
 export const DEFAULT_APP_NAME = "my-proofkit-app";
+export const NODE_RUNTIME_VERSION = "^22.0.0 || ^24.0.0 || ^26.0.0";
 export const cliName = "proofkit";
 export const npmName = "@proofkit/cli";
 export const DOCS_URL = "https://proofkit.proof.sh";
diff --git a/packages/cli/src/core/executeInitPlan.ts b/packages/cli/src/core/executeInitPlan.ts
index e02b90a8..8a877119 100644
--- a/packages/cli/src/core/executeInitPlan.ts
+++ b/packages/cli/src/core/executeInitPlan.ts
@@ -24,6 +24,7 @@ import { getBrowserOxlintConfig, getUltraciteInitCommand } from "~/helpers/ultra
 import {
   formatPackageManagerCommand,
   normalizeImportAlias,
+  parseCommandString,
   replaceTextInFiles,
   updateTypegenConfig,
 } from "~/utils/projectFiles.js";
@@ -86,7 +87,7 @@ function renderNextSteps(plan: InitPlan, additionalSteps: string[] = []) {
 }
 
 function getPackageScriptCommand(plan: InitPlan, scriptName: string) {
-  const [command, ...args] = formatPackageManagerCommand(plan.request.packageManager, scriptName).split(" ");
+  const [command, ...args] = parseCommandString(formatPackageManagerCommand(plan.request.packageManager, scriptName));
   if (!command) {
     throw new Error(`Unable to resolve ${scriptName} command for ${plan.request.packageManager}.`);
   }
@@ -436,6 +437,8 @@ export const executeInitPlan = (plan: InitPlan) =>
       yield* codegenService.runInitial(plan.targetDir, plan.request.packageManager);
     }
 
+    // plan.tasks.runFix is non-blocking: getPackageScriptCommand/processService.run can fail on fresh scaffolds.
+    // Effect.either also catches lint failures below and logs warnings; other errors still propagate.
     if (plan.tasks.runFix) {
       const fixCommand = getPackageScriptCommand(plan, "fix");
       yield* Effect.either(
@@ -448,16 +451,16 @@ export const executeInitPlan = (plan: InitPlan) =>
     }
 
     if (plan.tasks.runLint) {
-      const fixCommand = getPackageScriptCommand(plan, "fix");
+      const lintCommand = getPackageScriptCommand(plan, "lint");
       const result = yield* Effect.either(
-        processService.run(fixCommand.command, fixCommand.args, {
+        processService.run(lintCommand.command, lintCommand.args, {
           cwd: plan.targetDir,
           stdout: "pipe",
           stderr: "pipe",
         }),
       );
       if (result._tag === "Left") {
-        consoleService.warn("Lint fix did not succeed; continuing setup.");
+        consoleService.warn("Lint did not succeed; continuing setup.");
       }
     }
 
diff --git a/packages/cli/src/core/planInit.ts b/packages/cli/src/core/planInit.ts
index f69fb5a7..25b27553 100644
--- a/packages/cli/src/core/planInit.ts
+++ b/packages/cli/src/core/planInit.ts
@@ -1,6 +1,7 @@
 import path from "node:path";
 import type { PackageJson } from "type-fest";
 
+import { NODE_RUNTIME_VERSION } from "~/consts.js";
 import type { InitPlan, InitRequest, ProofKitSettings } from "~/core/types.js";
 import {
   getFmdapiVersion,
@@ -25,7 +26,6 @@ const SHARED_PNPM_BUILD_POLICY = {
 } as const;
 const NPM_PACKAGE_MANAGER_WARNING =
   "Warning: We strongly suggest using PNPM 11 or greater as your package manager to better protect your computer and your app.";
-const NODE_RUNTIME_VERSION = "^24.11.0";
 const NPM_MIN_RELEASE_AGE_DAYS = 1;
 
 export function createPnpmWorkspaceFileContent(appType: InitRequest["appType"]) {
diff --git a/packages/cli/src/helpers/intent.ts b/packages/cli/src/helpers/intent.ts
index ce8a9588..83c6a139 100644
--- a/packages/cli/src/helpers/intent.ts
+++ b/packages/cli/src/helpers/intent.ts
@@ -1,8 +1,8 @@
 import type { PackageManager } from "~/utils/packageManager.js";
-import { getTemplatePackageExecuteCommand } from "~/utils/projectFiles.js";
+import { getTemplatePackageExecuteCommand, parseCommandString } from "~/utils/projectFiles.js";
 
 function splitExecuteCommand(packageManager: PackageManager) {
-  const [command, ...args] = getTemplatePackageExecuteCommand(packageManager).split(" ");
+  const [command, ...args] = parseCommandString(getTemplatePackageExecuteCommand(packageManager));
   if (!command) {
     throw new Error(`Unable to resolve package execute command for ${packageManager}.`);
   }
diff --git a/packages/cli/src/helpers/ultracite.ts b/packages/cli/src/helpers/ultracite.ts
index 6ee96ea7..8a15406c 100644
--- a/packages/cli/src/helpers/ultracite.ts
+++ b/packages/cli/src/helpers/ultracite.ts
@@ -1,6 +1,6 @@
 import type { AppType } from "~/core/types.js";
 import type { PackageManager } from "~/utils/packageManager.js";
-import { getTemplatePackageExecuteCommand } from "~/utils/projectFiles.js";
+import { getTemplatePackageExecuteCommand, parseCommandString } from "~/utils/projectFiles.js";
 
 const ULTRACITE_EDITORS = ["universal", "cursor"] as const;
 const ULTRACITE_AGENTS = ["universal", "claude", "codex"] as const;
@@ -8,7 +8,7 @@ const ULTRACITE_HOOKS = ["cursor", "windsurf", "codebuddy", "claude"] as const;
 const ULTRACITE_INTEGRATIONS = ["husky", "lint-staged"] as const;
 
 function splitExecuteCommand(packageManager: PackageManager) {
-  const [command, ...args] = getTemplatePackageExecuteCommand(packageManager).split(" ");
+  const [command, ...args] = parseCommandString(getTemplatePackageExecuteCommand(packageManager));
   if (!command) {
     throw new Error(`Unable to resolve package execute command for ${packageManager}.`);
   }
diff --git a/packages/cli/src/utils/projectFiles.ts b/packages/cli/src/utils/projectFiles.ts
index d5484d03..465c14d0 100644
--- a/packages/cli/src/utils/projectFiles.ts
+++ b/packages/cli/src/utils/projectFiles.ts
@@ -7,6 +7,7 @@ import type { PackageManager } from "~/utils/packageManager.js";
 
 const commonFileMakerLayoutPrefixes = ["API_", "API ", "dapi_", "dapi"];
 const TRAILING_SLASH_REGEX = /[^/]$/;
+const WHITESPACE_REGEX = /\s/;
 const DEFAULT_FM_MCP_BASE_URL = "http://127.0.0.1:1365";
 const textFileExtensions = new Set([
   ".ts",
@@ -54,6 +55,60 @@ export function formatPackageManagerCommand(packageManager: PackageManager, comm
   return ["npm", "bun"].includes(packageManager) ? `${packageManager} run ${command}` : `${packageManager} ${command}`;
 }
 
+export function parseCommandString(command: string): string[] {
+  const tokens: string[] = [];
+  let current = "";
+  let quote: "'" | '"' | undefined;
+  let escaping = false;
+
+  for (const char of command) {
+    if (escaping) {
+      current += char;
+      escaping = false;
+      continue;
+    }
+
+    if (char === "\\") {
+      escaping = true;
+      continue;
+    }
+
+    if (quote) {
+      if (char === quote) {
+        quote = undefined;
+      } else {
+        current += char;
+      }
+      continue;
+    }
+
+    if (char === "'" || char === '"') {
+      quote = char;
+      continue;
+    }
+
+    if (WHITESPACE_REGEX.test(char)) {
+      if (current) {
+        tokens.push(current);
+        current = "";
+      }
+      continue;
+    }
+
+    current += char;
+  }
+
+  if (escaping) {
+    current += "\\";
+  }
+
+  if (current) {
+    tokens.push(current);
+  }
+
+  return tokens;
+}
+
 export function getTemplatePackageCommand(packageManager: PackageManager) {
   if (packageManager === "npm") {
     return "npm run";
diff --git a/packages/cli/template/vite-wv/package.json b/packages/cli/template/vite-wv/package.json
index 859ba883..f0d83da9 100644
--- a/packages/cli/template/vite-wv/package.json
+++ b/packages/cli/template/vite-wv/package.json
@@ -3,6 +3,9 @@
   "version": "0.0.0",
   "private": true,
   "type": "module",
+  "engines": {
+    "node": "^22.0.0 || ^24.0.0 || ^26.0.0"
+  },
   "scripts": {
     "build": "vite build",
     "build:upload": "__PNPM_COMMAND__ build && __PNPM_COMMAND__ upload",
diff --git a/packages/cli/template/vite-wv/src/routes/query-demo.tsx b/packages/cli/template/vite-wv/src/routes/query-demo.tsx
index e9dcd08d..785c36e4 100644
--- a/packages/cli/template/vite-wv/src/routes/query-demo.tsx
+++ b/packages/cli/template/vite-wv/src/routes/query-demo.tsx
@@ -7,7 +7,7 @@ const getConnectionHint = (): string =>
 export const QueryDemoPage = () => {
   const hintQuery = useQuery({
     queryFn: getConnectionHint,
-    queryKey: ["starter-connection-hint"],
+    queryKey: ["starter-connection-hint"] as const,
   });
 
   return (
diff --git a/packages/cli/tests/executor.test.ts b/packages/cli/tests/executor.test.ts
index 43db6dde..b0ca09bc 100644
--- a/packages/cli/tests/executor.test.ts
+++ b/packages/cli/tests/executor.test.ts
@@ -69,7 +69,7 @@ describe("executeInitPlan command paths", () => {
       ].join(" "),
       "pnpx @tanstack/intent@latest install",
       "pnpm fix",
-      "pnpm fix",
+      "pnpm lint",
     ]);
     expect(tracker.filemakerBootstraps).toBe(1);
     expect(tracker.codegens).toBe(1);
@@ -125,7 +125,7 @@ describe("executeInitPlan command paths", () => {
     expect(npmrcFile).toContain("min-release-age=1");
   });
 
-  it("warns and continues when final lint fix fails", async () => {
+  it("warns and continues when final lint fails", async () => {
     const cwd = await fs.mkdtemp(path.join(os.tmpdir(), "proofkit-lint-fix-warn-"));
     const console = {
       error: [] as string[],
@@ -161,13 +161,13 @@ describe("executeInitPlan command paths", () => {
         makeTestLayer({
           console,
           cwd,
-          failProcessCommand: "pnpm fix",
+          failProcessCommand: "pnpm lint",
           failures: {
             processRun: new ExternalCommandError({
-              args: ["fix"],
+              args: ["lint"],
               command: "pnpm",
               cwd,
-              message: "fix failed",
+              message: "lint failed",
             }),
           },
           packageManager: "pnpm",
@@ -177,7 +177,8 @@ describe("executeInitPlan command paths", () => {
     );
 
     expect(tracker.commands).toContain("pnpm fix");
-    expect(console.warn).toContain("Lint fix did not succeed; continuing setup.");
+    expect(tracker.commands).toContain("pnpm lint");
+    expect(console.warn).toContain("Lint did not succeed; continuing setup.");
   });
 
   it("supports force overwrite for an existing directory", async () => {
diff --git a/packages/cli/tests/init-run-init-regression.test.ts b/packages/cli/tests/init-run-init-regression.test.ts
index 3342d2ff..09502384 100644
--- a/packages/cli/tests/init-run-init-regression.test.ts
+++ b/packages/cli/tests/init-run-init-regression.test.ts
@@ -200,6 +200,7 @@ describe("runInit browser post-init typegen regression", () => {
 
   it("writes pnpm build policy before install for pnpm 10", async () => {
     mockState.appType = "webviewer";
+    execaMock.mockResolvedValue({ stdout: "10.0.0" });
 
     await expect(
       runInit("demo-webviewer", {
@@ -214,6 +215,19 @@ describe("runInit browser post-init typegen regression", () => {
       expect.stringContaining('  "sharp": false'),
       "utf8",
     );
+    const workspaceWriteCallIndex = writeFileSyncMock.mock.calls.findIndex(([filePath]) =>
+      String(filePath).endsWith("pnpm-workspace.yaml"),
+    );
+    const firstPnpmScriptCallIndex = execaMock.mock.calls.findIndex(
+      ([command, args]) => command === "pnpm" && Array.isArray(args) && args[0] !== "-v",
+    );
+    expect(workspaceWriteCallIndex).not.toBe(-1);
+    expect(firstPnpmScriptCallIndex).not.toBe(-1);
+    const workspaceWriteOrder = writeFileSyncMock.mock.invocationCallOrder[workspaceWriteCallIndex];
+    const firstPnpmScriptOrder = execaMock.mock.invocationCallOrder[firstPnpmScriptCallIndex];
+    expect(workspaceWriteOrder).toBeDefined();
+    expect(firstPnpmScriptOrder).toBeDefined();
+    expect(workspaceWriteOrder as number).toBeLessThan(firstPnpmScriptOrder as number);
     expect(execaMock).toHaveBeenCalledWith("pnpm", ["fix"], {
       cwd: "/tmp/proofkit-regression/demo-browser",
       stdio: "pipe",
diff --git a/packages/cli/tests/init-scaffold-contract.test.ts b/packages/cli/tests/init-scaffold-contract.test.ts
index 44a71aba..f1bfc070 100644
--- a/packages/cli/tests/init-scaffold-contract.test.ts
+++ b/packages/cli/tests/init-scaffold-contract.test.ts
@@ -3,6 +3,7 @@ import { existsSync, mkdirSync, readdirSync, readFileSync, rmSync } from "node:f
 import { join } from "node:path";
 import { parse as parseJsonc } from "jsonc-parser/lib/esm/main.js";
 import { beforeEach, describe, expect, it } from "vitest";
+import { NODE_RUNTIME_VERSION } from "~/consts.js";
 
 interface PackageJsonShape {
   version?: string;
@@ -182,10 +183,10 @@ describe("Init scaffold contract tests", () => {
     expect(packageJson.devEngines?.packageManager?.onFail).toBe("download");
     expect(packageJson.devEngines?.runtime).toEqual({
       name: "node",
-      version: "^24.11.0",
+      version: NODE_RUNTIME_VERSION,
       onFail: "download",
     });
-    expect(packageJson.engines?.node).toBe("^24.11.0");
+    expect(packageJson.engines?.node).toBe(NODE_RUNTIME_VERSION);
     expect(allProofkitDependenciesUseCurrentVersions(packageJson)).toBe(true);
     expect(readFileSync(join(browserProjectDir, "CLAUDE.md"), "utf-8")).toBe("@AGENTS.md\n");
     expect(readFileSync(join(browserProjectDir, ".cursorignore"), "utf-8")).toBe("CLAUDE.md\n");
@@ -245,10 +246,10 @@ describe("Init scaffold contract tests", () => {
     expect(packageJson.devEngines?.packageManager?.onFail).toBe("download");
     expect(packageJson.devEngines?.runtime).toEqual({
       name: "node",
-      version: "^24.11.0",
+      version: NODE_RUNTIME_VERSION,
       onFail: "download",
     });
-    expect(packageJson.engines?.node).toBe("^24.11.0");
+    expect(packageJson.engines?.node).toBe(NODE_RUNTIME_VERSION);
     expect(allProofkitDependenciesUseCurrentVersions(packageJson)).toBe(true);
     expect(readFileSync(join(webviewerProjectDir, "CLAUDE.md"), "utf-8")).toBe("@AGENTS.md\n");
     expect(readFileSync(join(webviewerProjectDir, ".cursorignore"), "utf-8")).toBe("CLAUDE.md\n");
diff --git a/packages/cli/tests/integration.test.ts b/packages/cli/tests/integration.test.ts
index bf47bf85..3bdcc4e5 100644
--- a/packages/cli/tests/integration.test.ts
+++ b/packages/cli/tests/integration.test.ts
@@ -3,6 +3,7 @@ import path from "node:path";
 import { Effect } from "effect";
 import fs from "fs-extra";
 import { describe, expect, it } from "vitest";
+import { NODE_RUNTIME_VERSION } from "~/consts.js";
 import { executeInitPlan } from "~/core/executeInitPlan.js";
 import { planInit } from "~/core/planInit.js";
 import { getProofkitDependencyVersion, getTypegenVersion, getVersion } from "~/utils/getProofKitVersion.js";
@@ -74,11 +75,11 @@ describe("integration scaffold generation", () => {
     });
     expect(packageJson.devEngines?.runtime).toEqual({
       name: "node",
-      version: "^24.11.0",
+      version: NODE_RUNTIME_VERSION,
       onFail: "download",
     });
     expect(packageJson.engines).toEqual({
-      node: "^24.11.0",
+      node: NODE_RUNTIME_VERSION,
     });
     expect(packageJson.proofkitMetadata).toMatchObject({
       scaffoldPackage: "@proofkit/cli",
diff --git a/packages/cli/tests/planner.test.ts b/packages/cli/tests/planner.test.ts
index a0c5c47d..558b60fa 100644
--- a/packages/cli/tests/planner.test.ts
+++ b/packages/cli/tests/planner.test.ts
@@ -1,5 +1,6 @@
 import path from "node:path";
 import { describe, expect, it } from "vitest";
+import { NODE_RUNTIME_VERSION } from "~/consts.js";
 import { planInit } from "~/core/planInit.js";
 import {
   getFmdapiVersion,
@@ -33,11 +34,11 @@ describe("planInit", () => {
     });
     expect(plan.packageJson.devEngines?.runtime).toEqual({
       name: "node",
-      version: "^24.11.0",
+      version: NODE_RUNTIME_VERSION,
       onFail: "download",
     });
     expect(plan.packageJson.engines).toEqual({
-      node: "^24.11.0",
+      node: NODE_RUNTIME_VERSION,
     });
     expect(plan.settings.appType).toBe("browser");
     expect(plan.packageJson.devDependencies["@proofkit/cli"]).toBe(proofkitCliVersion);
diff --git a/packages/cli/tests/test-layer.ts b/packages/cli/tests/test-layer.ts
index f848b0f2..e3d7d42b 100644
--- a/packages/cli/tests/test-layer.ts
+++ b/packages/cli/tests/test-layer.ts
@@ -348,11 +348,15 @@ export function makeTestLayer(options: {
       run: (command: string, args: string[]) => {
         const processCommand = [command, ...args].join(" ");
         tracker?.commands.push(processCommand);
+        const processRunFailure = options.failures?.processRun;
         if (options.failProcessCommand === processCommand) {
-          return Effect.fail(options.failures?.processRun as ExternalCommandError);
+          if (!processRunFailure) {
+            throw new Error("makeTestLayer requires failures.processRun when failProcessCommand is set.");
+          }
+          return Effect.fail(processRunFailure as ExternalCommandError);
         }
-        if (!options.failProcessCommand && options.failures?.processRun) {
-          return Effect.fail(options.failures.processRun as ExternalCommandError);
+        if (!options.failProcessCommand && processRunFailure) {
+          return Effect.fail(processRunFailure as ExternalCommandError);
         }
         return Effect.succeed({ stdout: "", stderr: "" });
       },
diff --git a/packages/create-proofkit/package.json b/packages/create-proofkit/package.json
index 688c2aef..4fec33e5 100644
--- a/packages/create-proofkit/package.json
+++ b/packages/create-proofkit/package.json
@@ -27,7 +27,7 @@
     "vitest": "^4.0.17"
   },
   "engines": {
-    "node": ">=20.12.0"
+    "node": "^22.0.0 || ^24.0.0 || ^26.0.0"
   },
   "publishConfig": {
     "access": "public"
diff --git a/packages/fmdapi/package.json b/packages/fmdapi/package.json
index 03d1417f..f0720a05 100644
--- a/packages/fmdapi/package.json
+++ b/packages/fmdapi/package.json
@@ -80,7 +80,7 @@
     "vitest": "^4.0.17"
   },
   "engines": {
-    "node": ">=18.0.0"
+    "node": "^22.0.0 || ^24.0.0 || ^26.0.0"
   },
   "files": [
     "src",
diff --git a/packages/fmodata/package.json b/packages/fmodata/package.json
index 32a2493a..d3b24e11 100644
--- a/packages/fmodata/package.json
+++ b/packages/fmodata/package.json
@@ -93,7 +93,7 @@
     "zod": "^4.3.5"
   },
   "engines": {
-    "node": ">=18.0.0"
+    "node": "^22.0.0 || ^24.0.0 || ^26.0.0"
   },
   "files": [
     "src",