Personality Reveal – multilingual online tests

Next.js 16 site with 100-question psychological tests in 32 European languages. Taking a test is free; the detailed personal report costs €1.99 and is emailed after payment via Stripe.

Getting started

npm install
cp .env.example .env.local   # fill in Stripe/SMTP settings (optional for local dev)
npm run dev

Without STRIPE_SECRET_KEY the dev server skips payment, shows the report on the thank-you page and "sends" it straight away. Without SMTP_HOST the email is logged to the console instead.

URL structure

URL	Page
/	Redirects to the visitor's language
/es	Home page with all tests (#tests)
/es/career	Test landing page (SEO)
/es/career/start	Gender choice, then the 100 questions
/es/career/result	Locked preview + email/checkout form
/es/career/thanks	Confirmation after payment

How it fits together

• content/definitions/<slug>.json – questions' scoring structure (dimensions, reverse items, outcome type)
• messages/<locale>/ui.json – interface texts; messages/<locale>/tests/<slug>.json – test texts
• content/tests.json – which tests are shown, in which order
• scripts/gen-registry.mjs – generates lib/generated/registry.ts (runs automatically before dev/build)
• npm run check:content – validates every definition and translation (counts, keys, placeholders)
• lib/tests/scoring.ts – scoring, incl. 16-types code, attachment style, political quadrant, PHQ-9/PCL-5
• app/api/checkout – creates a Stripe Checkout session; answers travel in the session metadata (no database)
• app/api/stripe/webhook – on payment renders the report (lib/report/render.ts) and emails it over SMTP
• /[locale]/[test]/thanks?session_id=… – verifies the payment with Stripe, shows the full report on the page and emails it if the webhook has not done so yet (lib/delivery.ts; a flag on the PaymentIntent prevents double sends)
• /[locale]/contact + app/api/contact – contact form, delivered over SMTP to NEXT_PUBLIC_CONTACT_EMAIL/CONTACT_FROM_EMAIL

Missing translations fall back to English per key, so a partially translated language still works. See docs/CONTENT_SPEC.md for the content format.

Going live (checklist)

1. Brand & domain

• Choose the final name and set NEXT_PUBLIC_SITE_NAME and NEXT_PUBLIC_SITE_URL (used in emails, PDFs, share images, sitemap).
• Replace app/icon.svg if you have your own logo.

2. Hosting (Vercel recommended)

1. Import the GitHub repo at vercel.com → New Project (framework is detected automatically).
2. Add every variable from .env.example under Settings → Environment Variables.
3. Add your domain under Settings → Domains and point DNS to Vercel.

3. Stripe

1. Copy the live secret key into STRIPE_SECRET_KEY.
2. Developers → Webhooks → add https://<domain>/api/stripe/webhook with events checkout.session.completed and checkout.session.async_payment_succeeded; copy the signing secret into STRIPE_WEBHOOK_SECRET.
3. Settings → Payment methods: enable cards, iDEAL, Bancontact, etc.
4. EU VAT: register for the OSS scheme, activate Stripe Tax (Settings → Tax), then set STRIPE_AUTOMATIC_TAX=true. The €1.99 price is VAT-inclusive; Stripe applies the customer country's rate.
5. Do one real test purchase and refund it.

4. Email (SMTP)

• Fill SMTP_HOST, SMTP_PORT, SMTP_USER, SMTP_PASS, CONTACT_FROM_EMAIL.
• Set up SPF, DKIM and DMARC for the sender domain at your mail provider, otherwise reports land in spam.

5. Legal (have a lawyer review)

• Company details in COMPANY_* (legal notice / Impressum, mandatory in DE/AT) and NEXT_PUBLIC_COMPANY_DETAILS.
• Review the privacy policy, terms, cookie and refund texts (messages/*/ui.json → legal).
• Checkout consent includes the EU waiver of the right of withdrawal for immediately delivered digital content.
• Have the PHQ-9 and PCL-5 items checked against the official translation for each language (messages/<locale>/tests/depression.json items 0–8, trauma.json items 0–19).

6. Monitoring & analytics

• Google Analytics 4: create a GA4 property, copy the measurement ID into NEXT_PUBLIC_GA_ID. A cookie banner asks for consent first; events test_start, test_complete, begin_checkout and purchase are sent once accepted. Mark purchase as a key event.
• Plausible: add the site, set NEXT_PUBLIC_PLAUSIBLE_DOMAIN, create goals Test Start, Test Complete, Checkout Start and Purchase (enable revenue tracking for Purchase).
• Set ERROR_WEBHOOK_URL (Slack/Discord/Teams incoming webhook) to get notified of server errors.
• Set ADMIN_TOKEN to resend reports: curl -X POST https://<domain>/api/admin/resend -H "authorization: Bearer $ADMIN_TOKEN" -H "content-type: application/json" -d '{"sessionId":"cs_live_…"}' (optionally "email":"other@address").

Validated questionnaires

The depression test embeds the PHQ-9 and the trauma test the PCL-5; both are public domain and are scored with their official cut-offs. ASRS (ADHD), MDQ (bipolar) and MSI-BPD are copyrighted and require a licence for commercial use, so those tests use original items covering the same symptom areas.