YuYin

YuYin is a Chinese pronunciation assistant that helps you learn Chinese pronunciation

www.yuyin.io · Added June 5, 2026 · Last analysed June 5, 2026 · via · 62% unique tagline

Own this Launch?

StackScope is a free public catalogue of indie launches. We find launches on Product Hunt, Hacker News and similar feeds, then crawl each site to detect its tech stack and score it for launch readiness: DNS, security headers, SEO basics. This page is what we saw on 5 June 2026; the live site may have changed since.

YuYin is missing several launch fundamentals. Visible gaps: missing several security headers, incomplete legal pages, and no robots.txt or sitemap.

Launched on Product Hunt on June 5, 2026. The site is hosted on Amazon.com in the United States. Our crawler found 9 technologies on this site, covering baas, DNS providers, business email, and frameworks. The stack includes Next.js, React, and Chakra UI.

Notably, it's on one of the most common stacks we track, shared by 1,289 launches.

If you own this site, refresh the snapshot and see the full fix list any time →

3.1

StackScope Score

Poor

52/100 Launch Readiness

Partially ready

1/6 Security Headers

Poor

2/3 Legal

Partial

0/2 Web Standards

Missing

100/100 Performance

Fast

Vibe Score 0 · No AI signals

Informational pattern-match signal. Does not feed the StackScope Score. See which fingerprints fired →

Tech Stack (9) · Indie stack

Infrastructure

DNS	Cloudflare DNS
Hosting	Vercel
Security	HSTS

Business email	Cloudflare Email Routing

Build & Framework

BaaS	Firebase
Framework	React
JavaScript library	i18next
Meta-framework	Next.js
UI library	Chakra UI

Infrastructure

Network

AMAZON-02 - Amazon.com, Inc., US

AS16509 · US

DNS

Cloudflare DNS

Authoritative nameserver

DNSSEC

Not enabled

DNS responses unsigned. Cache-poisoning vulnerable.

SSL Certificate

Let's Encrypt

Valid 3 Apr 2026 to 2 Jul 2026

Certificate as captured in this snapshot, not a live check.

Email Security

✓

SPF ~all Soft-fail (~all). Common and accepted.

DKIM Not detected at common selectors. Your provider may use a custom one.

✗

DMARC Not published. Receivers fall back to permissive defaults.

MTA-STS Not deployed. Mail to your domain can be downgraded to plaintext en route.

TLS-RPT Not configured. You won't hear about silent SMTP TLS handshake failures.

Storage (5)

Local storage (3)

Key	Size	Detected as
chakra-ui-color-mode	5 B	Chakra UI
i18nextLng	2 B	i18next
lpr64_user	4 B	-

IndexedDB (2)

Database	Version	Detected as
firebase-heartbeat-database	1	Firebase
firebaseLocalStorageDb	1	Firebase

Readiness Breakdown How?

✓ Custom title and meta description

✓ Responsive viewport meta tag

✓ Favicon present

- Open Graph tags (title, image, description)

- Canonical URL declared

- Twitter card meta tags

- Semantic HTML (nav, main, article)

Performance How?

195 ms Server response

72% Faster than peers

1336 ms Largest contentful paint

0.00 Cumulative layout shift

577 KB Page weight

0 Console errors

0 Failed requests

Indicative grade from a single automated render, not a substitute for Lighthouse or field data, and not part of the StackScope score.

AI Stance

No AI stance declared

✗ llms.txt published

✓ No AI bots blocked in robots.txt

Content-Signal

? No directive declared

Link headers

? None advertised

Well-Known Files

✗ robots.txt

✗ sitemap.xml

✗ security.txt

✗ llms.txt

✗ ads.txt

✗ humans.txt

Legal

? Privacy Policy not detected

✓ Terms of Service

Security Headers (1/6)

✗

Referrer-Policy

✗

X-Frame-Options

✗

Permissions-Policy experimental (check browser support)

✗

X-Content-Type-Options

✗

Content-Security-Policy

✓

Strict-Transport-Security

–

X-XSS-Protection deprecated (use Content-Security-Policy)

Build

✓ HTML minified

✗ CSS minified

✗ JS minified

✓ Code splitting

24 JS files

1 CSS files

0 Third-party domains

Brand Colours

Something not look right? If a technology shown here is wrong or out of date, email [email protected] and we'll review it.