DEV Community: gia ly bui

How to Choose the Best CS2 Case Opening Site — 2026 Comparison Guide

gia ly bui — Tue, 28 Jul 2026 14:50:42 +0000

After testing 20+ CS2 case opening sites over 6 months, here's what I learned.

The Criteria That Actually Matter

Provably Fair — Can you independently verify each roll? If not, skip.
Withdrawal Speed — Top sites process under 10 minutes.
Deposit Bonuses — Hellcase gives +10% on your first 3 deposits + a free daily case.
Community Trust — Check Trustpilot and Reddit r/csgo before depositing anywhere.
Longevity — Sites operating 5+ years are significantly safer.

The Top 3

Site	Since	Users	Bonus	Withdrawal
Hellcase	2016	5M+	+10% deposit + free daily case	<10 min
DatDrop	2017	2M+	5% deposit bonus	<15 min
CSGOFast	2015	1M+	Loyalty rewards	Instant

The Bottom Line

Stick to trusted platforms, always claim your free daily case, and never deposit more than you can afford to lose.

Full comparison with detailed reviews: https://cs2-case-sites.fly.dev

How to Build a WHOIS Lookup Tool for Free in 5 Minutes

gia ly bui — Tue, 21 Jul 2026 14:56:51 +0000

Ever needed to check who owns a domain? Here's how to build one using a free API — no registration, no API key, just a GET request.

The API

Domain WHOIS API on RapidAPI. 5,000 free requests/month. Read more at https://rapidapi.com/buigialy30206/api/domain-whois-api1/playground/apiendpoint_72a4be4a-8f73-4b30-a5e8-75ef1f165b40.

Step 1: Make a request

curl "https://mega-api-mellowed-tidepool-1271.fly.dev/whois/lookup?domain=github.com"

Step 2: Parse the response

({"registrar":"MarkMonitor","created":"2007-10-09","expires":"2028-10-09","nameservers":["ns1.github.com"]})

Step 3: Call it from JavaScript

async function lookupDomain(domain) {
  const res = await fetch(
    "<https://mega-api-mellowed-tidepool-1271.fly.dev/whois/lookup?domain=>" + domain
  );
  const data = await res.json();
  console.log(data);
}

lookupDomain("github.com");

That's it. No API key. No registration. No rate limits. Copy-paste and it works.

https://rapidapi.com/buigialy30206/api/domain-whois-api1/playground/apiendpoint_72a4be4a-8f73-4b30-a5e8-75ef1f165b40
https://www.producthunt.com/posts/steam-data-api

I Built 21 Free APIs in 3 Months — Here's What I Learned

gia ly bui — Tue, 14 Jul 2026 03:14:48 +0000

I'm a self-taught developer from China. Three months ago I had zero passive income. Today I have 21 APIs live on RapidAPI, all running on $0/month infrastructure.

Here's exactly how I did it, what worked, and what I wish I knew earlier.

The Stack (All Free)
Backend: FastAPI — $0

Hosting: Render Free Tier — $0

Health Check: UptimeRobot — $0

Monetization: RapidAPI — 20% commission

Total monthly infrastructure cost: $0.00

The Playbook

Pure Algorithm APIs Are Cheat Codes No external dependencies. No API keys. No rate limits. Write once, run forever.

QR Code Generator — Pure Python — Zero maintenance

Password Checker — Entropy math — Zero maintenance

UUID Generator — Python uuid — Zero maintenance

Markdown to HTML — Regex — Zero maintenance

These took 4 hours each. They've never broken once.

Free Public Data Sources Are Goldmines Wikidata → Company info for any business → Company Info API

RDAP Protocol → Domain registration data → Domain WHOIS API

OpenStreetMap → Business listings worldwide → Places Search API

All free. All global coverage. No API keys needed.

Caching Prevents Cold Starts Render's free tier sleeps after 15 minutes of inactivity. First request takes 50+ seconds.

Fix: UptimeRobot pings /health every 5 minutes. 50 monitors, all free.

The Numbers
After 3 months: 21 APIs, $0 monthly cost, 3+ APIs with growing traffic.

Best performer: Domain WHOIS API — 7.6K calls per week from a single user in Germany.

People are willing to pay for convenience. RDAP is free and well-documented, but wrapping it in a clean JSON API is worth real money.

What I'd Do Differently
Start with health endpoints. Lost weeks debugging cold starts that turned out to be missing /health routes.
Vary your categories. Data, Finance, Tools, Security — different search terms catch different buyers.
Write longer descriptions. RapidAPI search favors APIs with detailed markdown descriptions.
The APIs
Data: Domain WHOIS, Company Info, Email Validator, IP Geolocation, Places Search

Finance: Currency Converter, Stock Price, EU VAT Validator

Security: Password Checker

Tools: QR Code, Barcode, UUID, Markdown, Slug, User Agent Parser, PDF to Text

Search "buigialy30206" on RapidAPI to find all of them.

The real lesson: you don't need venture capital, a team, or a SaaS product. You need one free hosting provider, one free data source, one afternoon per API, and the willingness to ship.

The best passive income is the one that costs $0 to run.
https://www.producthunt.com/posts/steam-data-api

20 Free APIs on RapidAPI — The Complete List

gia ly bui — Fri, 10 Jul 2026 12:09:44 +0000

Over the past 3 weeks, I've built and published 20 APIs on RapidAPI. All free. All $0/month to run.

Categories:
📊 Business Data (3)
✅ Validation (4)
🔧 Generators (5)
🛠 Utilities (7)
📍 Location (1)

Every API listed on my profile. Free tiers on all of them.
https://www.producthunt.com/posts/steam-data-api
https://rapidapi.com/user/buigialy30206

7 Free Utility APIs That Replace Paid SaaS Tools

gia ly bui — Thu, 09 Jul 2026 11:23:35 +0000

URL Metadata — extract OG tags, favicon, title from any URL
Markdown to HTML — convert MD to HTML in one call
PDF to Text — extract text from PDF URLs
Language Detector — 55+ languages in one call
Sentiment Analysis — VADER lexicon, Positive/Negative/Neutral
User Agent Parser — browser, OS, device from UA strings
Currency Converter — 150+ currencies, live rates

All free. All on RapidAPI. All cost $0/month.
https://www.producthunt.com/posts/steam-data-api
https://rapidapi.com/user/buigialy30206

5 Free Generator APIs Every Indie Hacker Needs

gia ly bui — Wed, 08 Jul 2026 11:48:00 +0000

QR Code Generator — PNG or base64, customizable size
UUID Generator — v1 and v4, batch up to 100
Barcode Generator — Code128, EAN13, EAN8
Random User Generator — realistic fake profiles for testing
Text to Slug — any text → URL-friendly slug

No API keys. No limits for free tiers. All on RapidAPI.
https://www.producthunt.com/posts/steam-data-api
https://rapidapi.com/user/buigialy30206

I Built a Free Email Validator API — SMTP Handshake Explained

gia ly bui — Tue, 07 Jul 2026 10:46:09 +0000

Sending to invalid emails kills deliverability. Most validators cost $20-50/month.

Built my own. Three checks: syntax (regex), MX record (DNS), SMTP handshake (connect to mail server, ask "does this mailbox exist?", disconnect).

Stack: FastAPI + Python stdlib. Zero deps. $0/month. 1,000 free/month.

Search "Email Validator API" on RapidAPI.
https://www.producthunt.com/posts/steam-data-api
https://rapidapi.com/user/buigialy30206

I Built a Free Places Search API in One Day

gia ly bui — Mon, 06 Jul 2026 14:49:32 +0000

I needed business phone numbers for a sales project. Google Places wanted $0.03 per lookup. No thanks.

Built this over a weekend. Search "plumber in New York" → returns:

Business name
Phone number
Address
Website
GPS coordinates

60+ business types supported. Every country with OpenStreetMap data.

Stack: FastAPI + Render free tier + Overpass API

Total cost to run: $0/month. Free tier: 3,000 requests/month.
Paid plans from $29.99/month.

Search "Places Search API" on RapidAPI to try it.
Code on GitHub: github.com/buigialy30206-eng/google-maps-api
https://www.producthunt.com/posts/steam-data-api
https://rapidapi.com/user/buigialy30206

Why I Switched from Google Places API to a Free Alternative

gia ly bui — Sun, 05 Jul 2026 12:14:03 +0000

I was building a local business directory and needed location data. Google Places API pricing added up fast:

Text Search: $0.032 per call
Place Details: $0.017 per call
1,000 searches = $49 gone

So I looked for alternatives.

Found one built on OpenStreetMap data, hosted on RapidAPI. It's not Google-level coverage for every region, but for US/Europe cities it's solid.

What I get:

Business name, phone, address, website, GPS
60+ types (restaurant, hotel, pharmacy, gym...)
3,000 free requests/month
No API key sign-up

Stack behind it is FastAPI + Overpass API. The source code is on GitHub.

If you're prototyping or building something that doesn't need pixel-perfect data, this is worth a look. Search "Places Search API" on RapidAPI.
https://www.producthunt.com/posts/steam-data-api
https://rapidapi.com/user/buigialy30206

I built a free Places Search API — 60+ business types, worldwide, no API keys

gia ly bui — Sat, 04 Jul 2026 03:46:23 +0000

markdown I scrape data for a living and got tired of paying for business data APIs.

Built my own using OpenStreetMap. Returns structured JSON.

What it does
Search plumber in New York → name, phone, address, website, GPS
60+ types: restaurant, hotel, pharmacy, dentist, gym, bank...
Every country with OSM data
Free tier: 3,000 req/month
Tech
FastAPI + Render free tier + Overpass API. $0/month to run.

Links
API: API Hub — search "Places Search API"
Code: buigialy30206-eng/google-maps-api · GitHub
Feedback welcome!
https://www.producthunt.com/posts/steam-data-api
https://rapidapi.com/user/buigialy30206