Help developers discover SchemaLens 🚀

🐦 Twitter / X

SchemaLens is in the final days of the $100 AI Startup Race.

It's a free browser-based SQL schema diff tool that generates migration scripts instantly — no install, no signup, no data sent to servers.

Lifetime Pro is $39 one-time. If you review DB migrations, worth bookmarking.

→ https://schemalens.tech

#buildinpublic #postgresql #mysql #sql #devtools

💼 LinkedIn

If your team reviews database migrations, this free tool can save you hours — and catch breaking changes before they hit production.

SchemaLens compares two SQL schemas in your browser and generates the correct migration scripts. No CLI setup, no cloud upload, no account required.

I use it to review staging → production schema drift. It turns a tedious manual comparison into a 30-second check.

The project is in the final days of the $100 AI Startup Race. Lifetime Pro is $39 one-time.

Worth bookmarking for your next migration review.

→ https://schemalens.tech

#database #postgresql #mysql #sql #devtools #engineering

📧 Email to a teammate

Hey — found a tool you might like: SchemaLens (https://schemalens.tech)

It diffs two SQL schemas in the browser and generates ALTER TABLE migration scripts. I used it to review a schema drift and it caught a column type change I would have missed.

Free forever for the web diff. They’re in the final days of a $100 startup race, so Lifetime Pro is $39 one-time.

Worth keeping in your toolkit.

🗣️ Reddit — r/PostgreSQL

I built a browser-based schema diff tool for PostgreSQL (and MySQL/SQLite/SQL Server/Oracle). No signup, no upload, no backend.

I got tired of comparing schema dumps by hand when reviewing migration PRs. Text diffs are noisy and miss semantic meaning — like whether a column was renamed vs dropped and re-added.

SchemaLens parses CREATE TABLE statements, shows exactly what changed, and generates the correct ALTER TABLE script for your dialect. Everything parses client-side so your schema never touches a server.

Live: https://schemalens.tech

Lifetime Pro is $39 one-time. The web diff itself is free forever.

Would love feedback from real PostgreSQL users — especially on edge cases like composite PKs, enums, arrays, or exotic types.

🗣️ Reddit — r/MySQL

Compare MySQL schemas in your browser and generate ALTER TABLE scripts instantly

I built a tool that compares two MySQL schemas and generates the correct migration SQL — no install, no signup, no data upload.

SchemaLens parses your CREATE TABLE dumps, detects added/removed/modified columns, type changes, nullability flips, and default value changes, then outputs MySQL-specific ALTER TABLE syntax.

Key features for MySQL users:
- Handles AUTO_INCREMENT, backtick identifiers, and COLLATE
- Detects when a column change requires MODIFY COLUMN
- Shows visual diff before you run anything
- 100% client-side — paste your schema, it never leaves your browser

Try it: https://schemalens.tech

Web diff is free forever. Lifetime Pro is $39 one-time.

If you hit edge cases with MySQL-specific syntax, I'd love to know.

🗣️ Reddit — r/webdev

Built a zero-backend schema diff tool that runs entirely in the browser

For my side project I built SchemaLens — a SQL schema diff tool with zero backend. No server, no database, no API. Just vanilla JS parsing CREATE TABLE statements and generating migration scripts.

Tech stack:
- Vanilla HTML/CSS/JS
- Custom SQL tokenizer + parser
- Semantic diff engine
- Dialect-aware migration generator (PostgreSQL, MySQL, SQLite, SQL Server, Oracle)

What it does:
- Paste two schema dumps
- See tables added/removed/modified with color coding
- Get per-column change details
- Download migration SQL or export as Markdown for PRs

Why no backend? Your schema structure reveals a lot about your data model. Privacy is the default.

Live: https://schemalens.tech

Built in public. 313+ SEO pages, 80+ micro-tools, CI/CD integrations, and more.

Happy to answer questions about the parser, the diff algorithm, or the race.

🗣️ Reddit — r/SQL

SchemaLens (https://schemalens.tech) is a free browser-based schema diff tool I’ve been using. Paste two CREATE TABLE dumps, get a visual semantic diff + generated migration scripts.

Supports PostgreSQL, MySQL, SQLite, SQL Server, and Oracle. Runs entirely client-side so your schema never leaves the browser. Also has a CLI (`npx schemalens-cli`) if you prefer terminal workflows.

The project is in the final days of the $100 AI Startup Race. Lifetime Pro is $39 one-time. Web diff remains free forever.

💬 Hacker News — Show HN-style post

Show HN: SchemaLens — browser-based SQL schema diff with migration generation

SchemaLens compares two SQL CREATE TABLE dumps in the browser and generates dialect-correct migration scripts. No install, no signup, no backend.

Built in public. 313+ SEO pages, 80+ micro-tools, CI/CD integrations, and more.

Live: https://schemalens.tech

Why build this? I kept needing a quick way to check schema drift between staging and production without spinning up a CLI tool or connecting to a database. Text diffs of SQL dumps miss semantic changes (renamed column vs dropped/re-added, type widening vs narrowing). SchemaLens parses the DDL and shows the real diff.

Tech: vanilla JS, custom SQL tokenizer/parser, semantic diff engine. Everything runs client-side.

Free forever for the web diff. Lifetime Pro ($39 one-time) adds saved history, shareable links, and the full micro-tool library.

Would love feedback on parser edge cases and dialect coverage.

🚀 IndieHackers

SchemaLens — privacy-first SQL schema diff tool, built in public

I just launched SchemaLens, a browser-based SQL schema diff tool for PostgreSQL, MySQL, SQLite, SQL Server, and Oracle.

The problem: Reviewing database migrations by comparing two SQL dumps is tedious and error-prone. Text diffs miss semantic meaning. CLI tools require installation and database connections.

The solution: Paste two CREATE TABLE dumps into SchemaLens. Get an instant visual diff and a dialect-correct migration script. No install, no signup, no backend.

Why privacy-first matters: Your schema structure reveals a lot about your business logic. SchemaLens parses everything in the browser. Your data never touches a server.

Stack: Vanilla HTML/CSS/JS. Custom SQL parser. Vercel hosting.

Monetization: Web diff is free forever. Lifetime Pro at $39 one-time for saved history, shareable links, and 80+ micro-tools.

Live: https://schemalens.tech

Built in public over 12 weeks: 313 SEO pages, 80+ micro-tools, GitHub Action, VS Code extension, Chrome extension. Would love feedback from developers and indie hackers.

🐦 Twitter / X — Schema Lockfile Generator

New free tool from SchemaLens: a schema lockfile generator.

Paste a SQL dump, get a deterministic SHA-256 fingerprint + a GitHub Actions workflow that fails the build on unexpected schema drift.

No database connection. No signup. No data leaves your browser.

→ https://schemalens.tech/tools/schema-lockfile-generator.html

#postgresql #mysql #sqlite #sql #devtools #ci #githubactions

💼 LinkedIn — Schema Lockfile Generator

We just shipped a free schema lockfile generator for teams that want to gate deployments on schema state.

Instead of comparing raw SQL dumps (noisy, order-dependent, full of environment-specific defaults), SchemaLens canonicalizes the dump, sorts tables/columns, strips comments, and produces a deterministic SHA-256 fingerprint.

The output:
- A schema.lock JSON file you commit to git
- A ready-to-run GitHub Actions workflow that regenerates the hash in CI and fails on drift
- Support for PostgreSQL, MySQL, SQLite, SQL Server, and Oracle

It is completely client-side. Your schema dump never leaves the browser unless you run the optional CI script.

Useful for:
- Verifying that staging and production schemas still match
- Catching missing migration files
- Adding a lightweight gate before deployment

→ https://schemalens.tech/tools/schema-lockfile-generator.html

#database #postgresql #mysql #sql #devtools #ci #engineering

🔗 Short Link

Share this kit so others can spread the word too:

https://schemalens.tech/share-kit.html