Free, non-profit finance research & education. Markets, tools, open-source signal demos for India 🇮🇳 · US 🇺🇸 · UK 🇬🇧 · Crypto 🪙.
A single-person, non-profit finance education site. No advice, no tip groups, no paid signals, no affiliates. Everything free, everything open-source, every claim built on data.
- Frontend — static HTML/CSS/JS on GitHub Pages, custom domain, HTTPS.
- API — FastAPI + SQLite on a Hostinger Mumbai VPS, fronted by nginx + Let's Encrypt.
- Email — Resend (transactional + newsletter), two sender identities (
hello@andinsights@). - Analytics + ads — Google Analytics 4 + AdSense with Consent Mode v2 cookie banner.
- Content — 7 long-form articles, 4 working calculators, in-browser backtester, equity + crypto dashboards.
Everything on this site is educational. None of it is investment advice. The author is not SEBI / SEC / FCA / ESMA registered. Markets carry real risk — including total loss. Always consult a licensed adviser before investing. Full text:
/disclaimer.html,algo/disclaimer.md.
epicenter-exchange/
├── index.html # Home / hero / featured content
├── about.html # Mission, principles, what we don't do
├── services.html # Services profile (all free, no booking)
├── markets.html # Live equity + crypto dashboards
├── tools.html # SIP, EMI, Retirement, FX, Tax calculators
├── signals.html # In-browser backtester (SMA / RSI / MACD)
├── insights.html # Articles index + newsletter signup
├── contact.html # Contact form (POSTs to API)
├── disclaimer.html / privacy.html / cookies.html
├── 404.html
├── insights/ # 7 long-form articles
│ ├── sip-vs-lumpsum-india-2026.html
│ ├── nifty-vs-sp500-25-years.html
│ ├── best-tax-saving-investments-india-2026.html
│ ├── sebi-fo-rules-impact-2026.html
│ ├── xirr-vs-cagr-which-matters.html
│ ├── bitcoin-halving-cycles-explained.html
│ └── why-most-day-traders-lose-data.html
├── assets/
│ ├── css/style.css
│ └── js/
│ ├── main.js # Nav, consent banner, dark mode, year stamp
│ ├── ticker.js # Mixed equity + crypto marquee
│ ├── equity-dashboard.js # 13+ instruments via Stooq + CORS proxy
│ ├── crypto-dashboard.js # Top 12 coins via CoinGecko
│ ├── backtest.js # POSTs to /backtest, renders equity curve
│ ├── calculators.js # SIP/EMI/retirement/FX/tax math
│ ├── contact.js # POSTs contact form to API
│ └── newsletter.js # POSTs subscribe to API
├── api/ # ← FastAPI backend (runs on VPS)
│ ├── main.py # All endpoints + email + DB
│ ├── requirements.txt
│ └── .env.example
├── algo/ # Python research scripts (run locally)
│ ├── simple_signals.py # SMA / RSI / MACD
│ ├── advanced_signals.py # Z-score mean-reversion, 12-1 momentum, ATR sizing
│ ├── backtest.py # Vectorised backtester + metrics
│ └── requirements.txt
├── sitemap.xml · robots.txt · feed.xml · manifest.json · ads.txt
└── CNAME # epicenterexchange.com
Custom domain: epicenterexchange.com → Hostinger DNS → GitHub Pages A records:
185.199.108.153 185.199.109.153 185.199.110.153 185.199.111.153
Clean URLs. Every page is reachable without .html: /about, /services, /markets, /tools, /signals, /insights, /contact, /disclaimer, /privacy, /cookies, /insights/<slug>. GitHub Pages automatically serves /foo.html for /foo requests, so no rewrites needed.
Local preview:
python3 -m http.server 8000
# open http://localhost:8000Live base URL: https://api.epicenterexchange.com · version 1.3.0.
| Method | Path | Purpose |
|---|---|---|
GET |
/ |
Service banner |
GET |
/health |
Liveness check |
GET |
/backtest?asset=&ticker=&strategy=&days= |
Run SMA / RSI / MACD backtest |
GET |
/stats |
Cached site stats |
GET |
/quote?symbol= |
Single quote (Stooq) |
GET |
/history?symbol=&days= |
Daily history |
GET |
/crypto/spot?ids= |
CoinGecko spot |
GET |
/crypto/history?id=&days= |
CoinGecko history |
GET |
/forex?pair= |
FX pair |
POST |
/contact |
Save contact form + send 2 emails |
POST |
/newsletter/subscribe |
Subscribe + welcome email |
GET |
/newsletter/unsubscribe?token= |
One-click unsubscribe |
GET |
/diag/email |
SMTP diagnostic (no secrets in output) |
All endpoints CORS-locked to epicenterexchange.com (and localhost during dev). No API key required.
- Ubuntu 24.04 (arm64) on Hostinger Mumbai
- Python 3.12 venv at
/opt/epicenter-exchange/.venv - FastAPI + Uvicorn, listening on
127.0.0.1:8090 - nginx reverse-proxy with
proxy_pass http://127.0.0.1:8090 - TLS via Let's Encrypt (certbot, auto-renew)
- systemd unit
epicenter-api.service - SQLite database at
/opt/epicenter-exchange/data/epicenter.db
Run as ubuntu on the server.
# 1. System prep
sudo apt update && sudo apt install -y python3.12-venv nginx certbot python3-certbot-nginx git
# 2. Clone
sudo mkdir -p /opt/epicenter-exchange && sudo chown -R ubuntu:ubuntu /opt/epicenter-exchange
git clone https://github.com/devpilotX/epicenter-exchange.git /opt/epicenter-exchange
cd /opt/epicenter-exchange
# 3. Python env
python3 -m venv .venv
source .venv/bin/activate
pip install -r api/requirements.txt
mkdir -p data
# 4. Environment file — see ‘Environment variables’ below
cp api/.env.example api/.env
nano api/.env # paste real values; see warnings about ZWSP below
# 5. systemd service
sudo tee /etc/systemd/system/epicenter-api.service >/dev/null <<'EOF'
[Unit]
Description=Epicenter Exchange API
After=network.target
[Service]
User=ubuntu
WorkingDirectory=/opt/epicenter-exchange
EnvironmentFile=/opt/epicenter-exchange/api/.env
ExecStart=/opt/epicenter-exchange/.venv/bin/uvicorn api.main:app --host 127.0.0.1 --port 8090
Restart=always
RestartSec=3
[Install]
WantedBy=multi-user.target
EOF
sudo systemctl daemon-reload
sudo systemctl enable --now epicenter-api
sudo systemctl status epicenter-api --no-pager
# 6. nginx + HTTPS
sudo tee /etc/nginx/sites-available/api.epicenterexchange.com >/dev/null <<'EOF'
server {
listen 80;
server_name api.epicenterexchange.com;
location / {
proxy_pass http://127.0.0.1:8090;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
}
}
EOF
sudo ln -sf /etc/nginx/sites-available/api.epicenterexchange.com /etc/nginx/sites-enabled/
sudo nginx -t && sudo systemctl reload nginx
sudo certbot --nginx -d api.epicenterexchange.com --non-interactive --agree-tos -m you@example.com --redirect
# 7. Smoke test
curl https://api.epicenterexchange.com/health
curl https://api.epicenterexchange.com/diag/emailcd /opt/epicenter-exchange && git pull && sudo systemctl restart epicenter-api# Resend SMTP
SMTP_HOST=smtp.resend.com
SMTP_PORT=465
SMTP_USER=resend
SMTP_PASS=re_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx # 36-char Resend API key
# Senders (two identities, both verified in Resend)
FROM_EMAIL=hello@epicenterexchange.com
FROM_NAME=Epicenter Exchange
FROM_EMAIL_CONTACT=hello@epicenterexchange.com
FROM_NAME_CONTACT=Epicenter Exchange
FROM_EMAIL_NEWSLETTER=insights@epicenterexchange.com
FROM_NAME_NEWSLETTER=Epicenter Insights
NOTIFY_EMAIL=hello@epicenterexchange.com
# Public URLs
API_URL=https://api.epicenterexchange.com
SITE_URL=https://epicenterexchange.comWhen copying API keys or passwords from a browser, invisible Unicode characters (zero-width space U+200B, zero-width joiner U+200D, etc.) can stick to your clipboard and silently corrupt the value. Symptoms:
UnicodeEncodeError: 'ascii' codec can't encode character '\u200b' in position 44: ordinal not in range(128)
SMTP auth failed: (535, b'Authentication credentials invalid')
The API now strips invisibles on load, but the safest fix is at the source:
# When editing api/.env, paste then run this once to clean any invisibles in place:
sed -i 's/[\xE2\x80\x8B\xE2\x80\x8C\xE2\x80\x8D\xEF\xBB\xBF]//g' /opt/epicenter-exchange/api/.env
sudo systemctl restart epicenter-api
curl https://api.epicenterexchange.com/diag/email/diag/email returns booleans + lengths but never the secret. Look for "loaded": true, "smtp_user_set": true, "smtp_pass_len": 36.
- Add domain
epicenterexchange.comin Resend → add the displayed SPF, DKIM (resend._domainkey), and optional DMARC records in Hostinger DNS. Wait for all three to show Verified. - Sending only is enough for transactional + newsletter. The Receiving (Inbound) MX record is optional and only needed if you want Resend to receive replies.
- Create an API key in Resend → Settings → API Keys. Copy the 36-character
re_…value intoSMTP_PASS. Do not paste with surrounding whitespace. - Test:
Expected JSON:
curl -X POST https://api.epicenterexchange.com/contact \ -H 'Content-Type: application/json' \ -d '{"name":"test","email":"you@example.com","topic":"Bug report","message":"hello"}'
"email_sent": true. Then check your inbox (and spam folder once).
- GA4 stream
G-8GBZKT1BZL— loaded only after consent. - AdSense
ca-pub-6484525483464374— loaded always; runs in non-personalised mode until consent. - Consent Mode v2 — implemented in
assets/js/main.js. Default state: all storage signals denied. "Accept" setsad_storage,ad_user_data,ad_personalization,analytics_storageto granted. ads.txtat repo root:google.com, pub-6484525483464374, DIRECT, f08c47fec0942fa0- Privacy + cookies docs:
/privacy,/cookies.
- Google Search Console — add property, verify via DNS TXT, submit
sitemap.xml. Resubmit if it says "Couldn't fetch" — propagation can take 24-48h. - Bing Webmaster Tools — same flow.
- Communities — share educational posts (never recommendations) on r/IndiaInvestments, r/IndianStockMarket, Twitter #fintwit, LinkedIn finance groups. Each post links one specific article with the SEBI / RIA disclaimer in the comment.
- Twitter threads — the SEBI F&O 89%-lose data article works well as a 6-tweet thread.
- GitHub itself — the algo demos attract devs; stars/forks send referral traffic.
- Long-tail SEO — each
/insights/<slug>answers one specific question (e.g., "XIRR vs CAGR for SIP investors").
cd algo
python3 -m venv .venv && source .venv/bin/activate
pip install -r requirements.txt
python simple_signals.py --ticker RELIANCE.NS --strategy sma
python advanced_signals.py --ticker ^NSEI --strategy meanrev
python backtest.py --ticker AAPL --strategy macd --start 2005-01-01| Symptom | Likely cause | Fix |
|---|---|---|
/contact returns email_sent: false with UnicodeEncodeError |
ZWSP in SMTP_PASS |
Run the sed invisibles-strip above, restart service |
SMTP auth failed: (535, b'Authentication credentials invalid') |
Wrong / revoked Resend key, or key includes extra chars | Generate a fresh 36-char re_… key, paste cleanly |
/diag/email shows loaded: false |
.env not readable by service user |
chown ubuntu:ubuntu api/.env && chmod 640 api/.env |
| 502 from nginx | uvicorn not running | sudo systemctl status epicenter-api + journalctl -u epicenter-api -n 50 |
| Cert expired | certbot renew failed | sudo certbot renew --force-renewal |
| GSC "Couldn't fetch sitemap" | DNS or path glitch | Retry after 24h; verify curl https://epicenterexchange.com/sitemap.xml returns 200 |
GitHub Pages 404 on /about |
rare cache issue | Hard refresh; curl -I https://epicenterexchange.com/about should be 200 |
Solo project, but PRs welcome for typos, accessibility, more long-form articles, and additional educational backtest strategies. Read algo/disclaimer.md before touching signal code.
MIT — see LICENSE.
Built solo. Kept free. No advice, only education. 🕯️