Chytron

Two specialists wanted to move psychometric assessment - personality traits and study preferences - from paper and spreadsheets into a web app users can handle on their own. It started with students; today the platform serves everyone from age eleven to seniors. The result shouldn't end at a number: it should read clearly, be shareable with a psychologist or teacher, and revisitable over time.

Score credibility was key. To carry meaning, it has to be normed by age and gender - an eleven-year-old and a sixty-year-old simply aren't comparable.

A one-off engagement turned into a long-term collaboration - from the questionnaire data models through payments and emails to operations and security.

So I don't treat the product as a one-time delivery, but as a continuously evolving app I know inside out.

The app runs on Next.js and PostgreSQL via Prisma. At its core is a questionnaire editor in the admin: each characteristic carries questions, result texts for three score levels and eight norm sets (four age groups times two genders). Evaluation picks the right norm for the user's profile and flags pronounced traits that deviate from the group.

Around the tests sits a whole product: buying access via Stripe, gamification (points for activity, exchangeable to unlock sections) and sharing results with a parent, psychologist or teacher.

• Questionnaire editor with age-gender norming (8 sets per questionnaire)
• Sharing results with a parent, psychologist or coach
• Payments and access via Stripe, gamified section unlocking
• Operations, emails and security entirely on me
• Page caching, image optimization and observability via Sentry