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butterbase-aibutterbase-ai/butterbase-skills/skills/deploy-frontend/SKILL.md

deploy-frontend

Skill535 starsChanged 5 months agoMITView on GitHub

Use when deploying a frontend (React, Next.js, or static HTML) to a live URL on Butterbase, or when troubleshooting deployment issues like MIME type errors or blank pages

  • Installs packages
  • Sends data out

We split this skill into the rules it gives an agent

14 rules. About 0 are common, 4 are distinctive, and 10 are very specific to this project.

  • ≈0

    Common · estimate

    Many files like this have a rule of this kind.

  • ≈4

    Distinctive · estimate

    This author's own choices. Worth a look.

  • 10

    Very specific

    Tied to their project's names, files or tools. Probably skip.

  • Common
  • Distinctive
  • Very specific
  1. Very specific:

    Use manage_frontend with action: "set_env" to configure the API URL and app ID before building.

    line 26
  2. Distinctive:

    Run the framework-specific build command to produce the static output directory.

    line 49
  3. Very specific:

    After building, verify the output directory contains index.html at its root:

    line 57
  4. Very specific:

    If index.html is missing, check that the build completed without errors and that the framework is configured for static output.

    line 67
  5. Distinctive:

    Before deploying, configure CORS so the browser can make API requests from the deployment URL.

    line 73
  6. Very specific:

    Call manage_app with action: "update_cors".

    line 75
  7. Very specific:

    Always include http://localhost:5173 (Vite dev server default) for local development

    line 88
  8. Distinctive:

    If you don't yet know the exact deployment URL, you can update CORS again after Step 7

    line 91
  9. Very specific:

    Call create_frontend_deployment with the app_id and the correct framework flag from the reference table above.

    line 97
  10. Very specific:

    Call manage_frontend with action: "start_deployment" and the deployment_id from Step 4:

    line 229
  11. Distinctive:

    Check the browser console (F12) for JavaScript errors or failed network requests

    line 244
  12. Very specific:

    If you want Butterbase to run npm install + build on the server, skip Steps 2–6 and use the source-build flow:

    line 267
  13. Very specific:

    Do not use zip -r ../source.zip .

    line 275
  14. Very specific:

    If a docs/butterbase/00-state.md exists in the working directory, prefer invoking via /butterbase-skills:journey-frontend so the journey …

    line 298

≈ “Common” is an estimate: at least 1 in 5 of the 308,232 skill files we read have a rule of the same kind, not the same words. “Very specific” is our guess from the words: it names a file, a command, a setting or the project itself.

Keep what fits and drop the rest. Your version, ready for your agents.
Files
SKILL.md

Overview

7-step workflow for deploying static frontends to Butterbase. Covers building, CORS, zipping, uploading, and verification.


Framework Reference Table

FrameworkBuild commandOutput dirEnv prefixFramework flag
React (Vite)npm run builddist/VITE_react-vite
Next.js (static)next buildout/NEXT_PUBLIC_nextjs-static
Plain HTML(none)project rootN/Astatic

Note: Next.js requires output: 'export' in next.config.js to produce a static export.


Step 1: Set Environment Variables

Use manage_frontend with action: "set_env" to configure the API URL and app ID before building. These variables are injected at build time by the framework.

{
  "app_id": "app_abc123",
  "action": "set_env",
  "vars": {
    "VITE_API_URL": "https://api.butterbase.ai/v1/app_abc123",
    "VITE_APP_ID": "app_abc123"
  }
}
  • For Vite, prefix all public variables with VITE_
  • For Next.js, prefix with NEXT_PUBLIC_
  • For Create React App, prefix with REACT_APP_

set_env upserts; you can call it again to add or change variables.


Step 2: Build

Run the framework-specific build command to produce the static output directory.

FrameworkCommand
React (Vite)npm run build
Next.js (static)next build
Plain HTML(no build needed)

After building, verify the output directory contains index.html at its root:

# For Vite
ls dist/index.html

# For Next.js static export
ls out/index.html

If index.html is missing, check that the build completed without errors and that the framework is configured for static output.


Step 3: Configure CORS

Before deploying, configure CORS so the browser can make API requests from the deployment URL.

Call manage_app with action: "update_cors". Pass the deployment URL (use the Butterbase Pages URL pattern) and any local dev origins:

{
  "app_id": "app_abc123",
  "action": "update_cors",
  "allowed_origins": [
    "https://your-app.pages.dev",
    "http://localhost:5173"
  ]
}
  • Always include http://localhost:5173 (Vite dev server default) for local development
  • Include http://localhost:3000 if using Next.js or Create React App locally
  • Origins must include the protocol (https:// or http://) and must not have trailing slashes
  • If you don't yet know the exact deployment URL, you can update CORS again after Step 7

Step 4: Create Deployment

Call create_frontend_deployment with the app_id and the correct framework flag from the reference table above.

{
  "app_id": "app_abc123",
  "framework": "react-vite"
}

The response contains:

  • deployment_id — save this for Step 7
  • uploadUrl — the presigned S3 URL for uploading the zip (expires in 15 minutes)

Free plan: 1 deployment per app. Deploying again automatically replaces the previous deployment — no need to delete first.


Step 5: Create Zip (Node archiver — the only supported method)

⚠️ Do not use Compress-Archive, File Explorer, or zip -r from outside the build dir. Windows built-in tools write backslash (\) path separators, which makes the platform serve every file as text/html and breaks JS/CSS with MIME errors. Zipping from the parent dir nests dist/ inside the archive and ships a blank page.

Butterbase's recommended cross-platform method is the archiver Node package. It always writes POSIX / separators (works identically on macOS, Linux, Windows PowerShell, cmd, Git Bash, WSL) and zips from inside the source dir so index.html lands at the zip root.

One-time setup in the project being deployed:

npm install --save-dev archiver
mkdir -p scripts

Then save this as scripts/make-zip.mjs (copy verbatim):

#!/usr/bin/env node
/**
 * Butterbase frontend zipper — the only supported way to compress a build
 * for `create_frontend_deployment` / `create_from_source`.
 *
 * Usage:
 *   node scripts/make-zip.mjs <sourceDir> <outZip> [--exclude=glob,glob,...]
 *
 * Examples:
 *   node scripts/make-zip.mjs dist frontend.zip                # Vite
 *   node scripts/make-zip.mjs out  frontend.zip                # Next.js static export
 *   node scripts/make-zip.mjs .    source.zip \                # source-build flow
 *     --exclude=node_modules,.next,dist,out,.git,.turbo,.cache
 */
import { createWriteStream } from "node:fs";
import { stat } from "node:fs/promises";
import { resolve } from "node:path";
import archiver from "archiver";

const [, , srcArg, outArg, ...rest] = process.argv;
if (!srcArg || !outArg) {
  console.error(
    "usage: node make-zip.mjs <sourceDir> <outZip> [--exclude=glob,glob,...]"
  );
  process.exit(2);
}

const src = resolve(srcArg);
const out = resolve(outArg);

const excludeFlag = rest.find((a) => a.startsWith("--exclude="));
const excludes = excludeFlag
  ? excludeFlag
      .slice("--exclude=".length)
      .split(",")
      .map((s) => s.trim())
      .filter(Boolean)
      .flatMap((g) => [g, `${g}/**`])
  : [];

const srcStat = await stat(src).catch(() => null);
if (!srcStat?.isDirectory()) {
  console.error(`error: source is not a directory: ${src}`);
  process.exit(1);
}

const output = createWriteStream(out);
const archive = archiver("zip", { zlib: { level: 9 }, forceLocalTime: true });

output.on("close", () => {
  const mb = (archive.pointer() / (1024 * 1024)).toFixed(2);
  console.log(`wrote ${out} (${mb} MB, ${archive.pointer()} bytes)`);
});
archive.on("warning", (err) => {
  if (err.code === "ENOENT") console.warn(err);
  else throw err;
});
archive.on("error", (err) => {
  throw err;
});

archive.pipe(output);
// cwd: src + glob('**/*') ⇒ entries are relative to src, so index.html
// sits at the zip root. archiver normalises separators to '/' on every OS.
archive.glob("**/*", { cwd: src, dot: true, ignore: excludes });
await archive.finalize();

Run it:

FrameworkCommand
Vitenode scripts/make-zip.mjs dist frontend.zip
Next.js (static)node scripts/make-zip.mjs out frontend.zip
Plain HTMLnode scripts/make-zip.mjs . frontend.zip --exclude=node_modules,.git

The script prints the final size on success — must be ≤ 100 MB for static deploys, ≤ 50 MB for source-build.


Step 6: Upload

Upload the zip file to the presigned S3 URL returned in Step 4:

curl -X PUT "{uploadUrl}" \
  -H "Content-Type: application/zip" \
  --data-binary @frontend.zip
  • Replace {uploadUrl} with the full presigned URL from Step 4
  • The upload URL expires in 15 minutes — if it expires, repeat Step 4 to get a new one
  • Maximum file size: 100 MB
  • A successful upload returns an empty 200 response with no body

Step 7: Start & Verify

Call manage_frontend with action: "start_deployment" and the deployment_id from Step 4:

{
  "app_id": "app_abc123",
  "action": "start_deployment",
  "deployment_id": "uuid-1234"
}
  • The tool polls until the deployment status is READY (up to 5 minutes)
  • On success, it returns the live URL (e.g., https://your-app.pages.dev)

Verification checklist:

  1. Open the live URL in a browser
  2. Check the browser console (F12) for JavaScript errors or failed network requests
  3. Navigate to a non-root route to verify SPA routing works (auto-handled for react-vite and nextjs-static)
  4. Make an API call and confirm it succeeds (no CORS errors)

Troubleshooting

ProblemCauseFix
Blank pageindex.html not at zip rootRe-zip with the supported script: node make-zip.mjs dist frontend.zip
MIME type errors / broken JS/CSSWindows backslash in zip paths (Compress-Archive, File Explorer)Re-zip with node make-zip.mjs dist frontend.zip — archiver writes POSIX / on every OS
API calls return 403CORS not configuredAdd deployment URL via manage_app action update_cors
Routes return 404SPA routing not set upSPA routing is auto-handled for react-vite and nextjs-static framework flags
Deploy stuck in BUILDINGBuild errorCheck manage_frontend action list_deployments for error field
Upload fails or curl errorsUpload URL expiredGet a new URL by calling create_frontend_deployment again
Next.js pages not exportingMissing static export configAdd output: 'export' to next.config.js and rebuild
Environment variables not foundNot set before buildRun manage_frontend action set_env and rebuild — env vars are baked in at build time

Bonus: server-side build (no local build needed)

If you want Butterbase to run npm install + build on the server, skip Steps 2–6 and use the source-build flow:

  1. manage_frontend action create_from_source → returns presigned URL for a source-code zip (≤ 50 MB)
  2. Zip the source with make-zip.mjs (same script as Step 5), excluding build artefacts:
    node scripts/make-zip.mjs . source.zip \
      --exclude=node_modules,.next,dist,out,.git,.turbo,.cache
    Do not use zip -r ../source.zip . -x ... — it has the same Windows-separator hazard as Step 5.
  3. curl -X PUT "{uploadUrl}" -H "Content-Type: application/zip" --data-binary @source.zip
  4. manage_frontend action start_from_source with deployment_id, lockfile_hash (sha256 of package-lock.json), optional build_command, output_dir, package_manager, user_env

Same lockfile_hash across deploys = cached node_modules for faster rebuilds.


Edge SSR (Next.js / Remix with server-side rendering)

Static deploys can't run server-side code. For Next.js (App Router with SSR/middleware) or Remix on Cloudflare Workers, use manage_edge_ssr instead of create_frontend_deployment + manage_frontend. Same shape, separate tool:

ActionPurpose
createReturns presigned URL for a pre-built Workers zip (framework default nextjs-edge)
startUploads + deploys; polls ≤ 60s
create_from_source / start_from_sourceServer-side build flow (defaults: npx @cloudflare/next-on-pages, output .vercel/output/static)
listHistorical edge deployments

Frameworks: nextjs-edge, remix-edge, other-edge.


If a docs/butterbase/00-state.md exists in the working directory, prefer invoking via /butterbase-skills:journey-frontend so the journey orchestrator stays in sync.

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