Everything needed to take Dev Workbench from zero to its first 5,000 stars: a pre-launch checklist, ready-to-post copy for Hacker News, Reddit and Product Hunt, and a week-by-week growth plan.

Replace {{DEMO_URL}} with https://zzoraemon043.github.io/dev-workbench/ and {{REPO_URL}} with https://github.com/zzoraemon043/dev-workbench before posting.

One-liner: The offline-first developer toolbox. Paste anything — it figures out the rest.

The hook (lead with this everywhere): You paste production JWTs and customer JSON into random websites every week. Those sites can log everything. Dev Workbench does the same jobs in a static page that never makes a network request.

Three proof points, in this order:

1. Smart paste — paste a JWT, JSON, wss:// URL, base64 blob or epoch timestamp anywhere and the right tool opens with the right decoder.
2. Zero backend, verifiable — open DevTools → Network while using it. Nothing. Share links live in the URL fragment, which is never sent to servers.
3. It feels like a native app — command palette, Alt+1…6, drag-and-drop, PWA install, light/dark.

Audience: full-stack and backend developers, API integrators, security-conscious teams that ban online formatters.

• Enable GitHub Pages (Settings → Pages → Source: GitHub Actions) and confirm the live demo loads.
• Repository description: The offline-first developer toolbox: JSON, Regex, JWT, Diff, encoders & WebSocket debugging in one zero-backend tab.
• Repository website: the demo URL.
• Topics: developer-tools, devtools, json, regex, jwt, diff, base64, websocket, offline-first, pwa, privacy, react, typescript, vite, tailwindcss.
• Social preview image (Settings → General): 1280×640, dark JSON Studio screenshot with the one-liner on top.
• Record a 20–30 second GIF/MP4: paste a JWT → auto-routes → claims + countdown → Alt+2 → regex highlight → Ctrl+K palette. Put it at the top of the README.
• Enable Discussions; pin a "Which tool should we build next?" thread.
• Create 8–10 good first issue tickets from the README roadmap (cron explainer, cURL ⇄ fetch, JSON Schema, RS256 verification…). New visitors who see easy issues become contributors.
• Cut a v1.0.0 release with notes and screenshots — releases show up in followers' feeds.
• Test the demo on Chrome, Firefox, Safari and a phone. First impressions are unforgiving.

When: Tuesday–Thursday, 8:00–10:00 a.m. US Eastern. Post it yourself from an account with some history. Stay in the thread for the first 3 hours and answer every comment.

Rules to respect: link directly to the demo or repo, no marketing superlatives in the title, never ask anyone for upvotes (vote rings get detected and the post is killed).

Show HN: Dev Workbench – JSON, JWT, regex and diff tools that never leave your browser

Show HN: An offline developer toolbox where you paste anything and it picks the tool

{{DEMO_URL}}

Hi HN, I built Dev Workbench because I kept pasting production JWTs and customer
payloads into whatever "online JSON formatter" Google showed me, and at some
point realized I had no idea what those sites log.

It's a static React app — no backend, no analytics, no third-party scripts.
You can verify it in the Network tab. It bundles the tools I reach for every day:

- JSON Studio: validation with line/column errors, a tree with click-to-copy
  JSONPath, JSONPath queries, and JSON -> TypeScript interfaces (optional keys
  and unions inferred across array items)
- Regex Lab: live highlighting, capture groups, replace preview, and a
  token-by-token plain-English explanation. Matching runs in a Web Worker with
  a 1.5s watchdog, so (a+)+$ can't freeze the tab
- JWT Inspector: claims with a live expiry countdown, HS256/384/512
  verification via Web Crypto, and "edit payload & re-sign" for test tokens
- Diff Studio: Myers diff with word-level highlights
- Codec Pipeline: chain base64/url/hex/hash/case/timestamp transforms and
  drag to reorder (think CyberChef-lite)
- Socket Console: a small WebSocket client with a JSON-aware frame log

The part I'm happiest with is smart paste: hit Cmd+V anywhere outside an editor
and it detects whether you pasted a JWT, JSON, a ws:// URL, base64 or an epoch
timestamp and opens the right tool. Share links compress the tool state into the
URL fragment with CompressionStream, so sharing still doesn't involve a server
(and HMAC secrets are deliberately excluded).

Stack: Vite, React 19, TypeScript (strict), Tailwind v4, Zustand. MIT licensed.

Code: {{REPO_URL}}

I'd love feedback on which tool is missing from your daily workflow — RS256
verification and a cURL <-> fetch converter are next on my list.

Space posts at least 2–3 days apart, adapt each one to the subreddit, and reply to every comment. Read each subreddit's self-promotion rules first; on most, you should be an active participant, not just a poster.

Title

[Showoff Saturday] I built an offline developer toolbox — paste a JWT/JSON/base64/ws:// URL anywhere and it opens the right tool

Body

I got tired of juggling 6 bookmarked "online formatter" sites (and of wondering
what they log), so I built Dev Workbench: one tab, zero backend, works offline.

Demo: {{DEMO_URL}}
Source (MIT): {{REPO_URL}}

What's inside:
• JSON Studio — tree view, JSONPath queries, JSON → TypeScript interfaces
• Regex Lab — live highlights, capture groups, plain-English explanations
• JWT Inspector — claims, expiry countdown, HS256 verify + re-sign
• Diff Studio — word-level side-by-side diffs
• Codec Pipeline — drag-and-drop chains of base64/url/hex/sha/case transforms
• Socket Console — WebSocket client with a JSON-aware frame log

Front-end details people here might enjoy:
• Regex matching runs in a Web Worker that gets terminated after 1.5s, so
  catastrophic backtracking can't hang the UI
• Share links = tool state → CompressionStream('deflate-raw') → base64url →
  URL fragment. No server, no database
• Native <dialog> for the command palette, Tailwind v4 CSS-variable theming,
  every tool lazy-loaded (~90 KB gzipped initial JS)

Built with Vite + React 19 + TypeScript + Tailwind v4 + Zustand. Feedback and
feature requests very welcome — what tool do you open the most?

r/programming prefers technical substance over product announcements. Post a write-up and link the repo from it.

Title

Building a zero-backend developer toolbox: Myers diff, regex sandboxing with Web Workers, and share links that never touch a server

Body / blog outline (publish on dev.to or your blog, then submit the article link)

1. The problem: online formatters are a data-leak vector. Examples of what developers paste.
2. Constraint: "no network by construction" — what that rules out and what the web platform gives you instead (Web Crypto, CompressionStream, Service Workers).
3. Myers' O(ND) diff in ~60 lines, plus the trick of snapshotting only diagonals [-d-1, d+1] to keep memory at O(D²).
4. Sandboxing untrusted regexes: why RegExp can't be interrupted and how a terminable Worker with a watchdog solves it.
5. Inferring TypeScript types from JSON: merging shapes across array items into optional keys and unions.
6. Stateless sharing with compressed URL fragments, and why fragments are never sent to servers.
7. Link: {{REPO_URL}} — MIT, contributions welcome.

• r/javascript — focus on the Web Worker regex watchdog.
• r/reactjs — focus on the plugin-style tool registry and lazy loading.
• r/selfhosted — focus on "static files, host it behind your VPN, nothing phones home".
• r/netsec / r/AskNetsec — focus on "stop pasting tokens into third-party sites" (be educational, not promotional).

When: 12:01 a.m. Pacific, Tuesday–Thursday. Ask a well-followed hunter only if you have one; self-hunting is fine. Line up 10–20 people who genuinely use it to leave thoughtful comments (not just upvotes) during the day.

Name: Dev Workbench

Tagline (60 chars max)

Paste anything: the private, offline toolbox for developers

Topics: Developer Tools, Open Source, Privacy, Productivity

Description (260 chars max)

JSON, regex, JWT, diff, encoder pipelines and a WebSocket console in one beautiful tab. Paste anything and it opens the right tool. 100% client-side: no backend, no tracking, works offline. Free and open source (MIT).

Gallery (in this order):

1. Hero: dark JSON Studio with the tagline overlaid
2. 30-second demo video (smart paste → JWT → regex → palette)
3. JWT Inspector with "Signature verified" and expiry countdown
4. Regex Lab with highlights and explanations
5. Codec Pipeline drag-and-drop
6. Light-mode JSON → TypeScript

Maker's first comment

Hey Product Hunt,

I'm the maker of Dev Workbench. Like most developers, I used to paste JWTs,
API responses and config files into whatever online formatter came up first —
until I realized I had no idea what those sites were logging.

Dev Workbench is my answer: a single, fast tab with the tools I use daily, built
so that nothing you paste ever leaves your browser. There's literally no backend.

A few things I'm proud of:
- Smart paste: Cmd/Ctrl+V anywhere and it detects JWT, JSON, URLs, base64,
  timestamps and WebSocket endpoints, then opens the right tool
- Offline JWT verification and re-signing with the Web Crypto API
- Drag-and-drop transform pipelines (base64 → JSON → …)
- Share links that store state in the URL itself — still no server
- Command palette and shortcuts for everything

It's free and MIT-licensed. I'd love to hear which tool you'd want next!

Complete the pre-launch checklist. Get 5–10 friends to try it and fix every rough edge they hit.

Day 1 Show HN → Day 3 r/webdev (Showoff Saturday) → Day 5 Product Hunt → Day 6 X/Bluesky video. Reply to everything within the hour. Turn every feature request into a GitHub issue and link it back in the thread — visible responsiveness converts visitors into stargazers.

Ship one visible improvement per week (start with the most requested tool) and announce each one. Publish the r/programming technical article. Submit to newsletters and awesome lists. Thank first-time contributors publicly.

• Monthly releases with GIFs in the notes.
• A "Tool of the month" contributor challenge in Discussions.
• Embed mode (?embed=1) so docs sites and blogs can embed a tool — every embed is a backlink.
• A browser extension that opens Workbench on selected text.

• docs/screenshots/*.png — already in the repo
• Social preview image, 1280×640
• Product Hunt thumbnail, 240×240 (the logo on a gradient)
• 30-second demo video (MP4 and GIF under 10 MB)
• 3 short clips: smart paste, regex watchdog, drag-and-drop pipeline