Pilat'1: the association's website and app

Context

A Pilates association managed its registrations, cheques and attendance lists on paper and in spreadsheets. It needed a website to present itself and receive trial requests, and a simple tool for the board and the coaches.

What I built

For the public

• A website with the class slots, computed remaining places (then "Full, waiting list"), trial-class requests and registration.
• Online payment through HelloAsso, in one or three instalments, linked straight to the membership. Or cheque, transfer, cash.

For the board

• Season dashboard: members and places, fees received and outstanding, cheques to cash, documents to collect, trial requests to handle.
• From trial request to registration in one click, balance reminders by e-mail, PDF certificates for works councils or health insurers, CSV export.
• A season calendar that removes public and school holidays (official open data).

For coaches: an installable app (PWA)

• Class attendance from the phone, adding a walk-in.
• Messages to students, opt-in push notifications, coach invoices.
• A coach only sees their slots and their students.

Technical points

• Three nested roles (coach, board, admin) and fine-grained per-action rights.
• Security: CSRF tokens on every action, antivirus-scanned uploads, signature stored outside the public site, bank details never published.
• Data minimisation: no health data collected, only "certificate received" or not.
• Measured performance: I wrote an audit command that crawls every back-office page with each role and reports the number of SQL queries, the most repeated query (to spot an N+1 whatever the data volume), page weight and estimated load time on 4G and 5G.
• Automated deployment: database and secrets created on first deploy, migrations on every release.