Fitness and beauty · Web system with an installable app (PWA)
PH Fitness
Complete gym system: front desk, memberships, classes, workouts, fitness assessments, sales and a student app on the phone.
- Client
- Gym running NexiaFit, the NexiaLabs management system
- Where
- Brazil
- Technology
- PHP 8 · MySQL · PDO · JavaScript · CSS · PWA · WhatsApp · Hostinger
- Status
- Live · phfitness.nexialabs.com.br
- Development
- André Gomes · NexiaLabs
In short
PH Fitness runs NexiaFit, a gym management system built by André Gomes at NexiaLabs. It covers the front desk with access control, contracts and monthly fees, a class schedule with a waiting list, workout plans, fitness assessments, counter sales, WhatsApp billing and an installable app for students. It is written in PHP 8 with MySQL, with no framework and no external dependencies, in its own instance on Hostinger hosting.
The client
Small gyms often track members in notebooks, spreadsheets and WhatsApp chats, and the numbers never add up at the end of the month. PH Fitness is one of the NexiaFit installations, a product André designed for gyms, boxes and studios. Each gym gets its own address, database and visual identity, with the house color and logo. The gym's public page, the staff panel and the student app all come from the same system.
The challenge
At the front desk there is one question: can this member come in? The answer depends on an active contract, a freeze, a late fee within the grace period and the plan's weekly limit. Behind that there is money: a payment cannot be recorded twice, a renewal cannot lose a paid day and a billing message cannot go out twice for the same event. Everything had to run on shared hosting, with no background process, and be simple for whoever is at the counter.
What was built
André put every business rule in a single module, so the panel, the API and the student app always give the same answer. The front desk searches by name, member number, CPF or phone and answers with a traffic light: cleared, cleared with a warning or blocked, with a button to take payment or renew right there. A scheduled routine produces birthday greetings, late notices with PIX details in the text, due date reminders and messages for members who stopped coming, and a unique key prevents repeats. Students install the app, see their workout, book classes, copy the PIX code and send the receipt, which the front desk approves from a queue. The owner gets a dashboard with revenue, churn, overdue payments and class occupancy.
What the system does
- Traffic light front desk that checks contract, freeze, overdue fees and weekly limit before letting a member in.
- Contracts with automatically generated installments, freezes that extend the term and early renewal without losing a paid day.
- Class schedule with capacity limits and a waiting list that notifies the next person when a spot opens.
- Workout plan builder and Jackson and Pollock fitness assessment with calculations verified on the server.
- Automatic and one click WhatsApp messages, sent manually, through Evolution API or through the official API.
- Installable student app with today's workout, class booking, PIX copy and paste and receipt upload.
- Counter sales with stock control, store credit charged to the member's account and a printable receipt.
- Owner dashboard with revenue, churn, estimated lifetime value, overdue debt by age and an attendance heat map.
// For whoever reviews the code: architecture and decisions.
Under the hood
NexiaFit is PHP 8 with PDO and MySQL, plain HTML, CSS and JavaScript, with no npm, no composer and no CDN scripts. Rules live in a domain module, payments in a single engine and metrics in their own file; the panel and the student app consume a PHP API. Each gym is an instance with its own subdomain, folder and database within the same Hostinger account, created by a provisioning script and updated by idempotent migrations. The student app is a per instance PWA, with a manifest and icon generated from the gym's logo and a service worker that never caches API responses. Automations run from the hosting panel's cron.
Technical decisions
- Every write is locked both on screen and on the server, with an UPDATE conditioned on the expected state or an INSERT with a unique key, so a repeated click never writes twice.
- Messages keyed by type and reference, shared by the cron job and the manual button, so the panel and the routine never send the same reminder twice.
- Plain PHP with no dependencies, because it runs on any shared hosting and a new gym can be set up in minutes.
- PIX copy and paste code generated by the system itself, following the EMV standard with CRC16, with no payment gateway.
Does your business look like this one?
Gyms, cross training boxes and studios that want to stop tracking members in spreadsheets and collect fees without awkwardness.
Frequently asked questions
Who developed PH Fitness?
PH Fitness was developed by André Gomes Andrade, a full stack developer from Carlos Chagas, Minas Gerais, Brazil, at NexiaLabs, from planning to launch.
Where is the client of PH Fitness based?
Gym running NexiaFit, the NexiaLabs management system. Brazil.
Which technologies were used to build PH Fitness?
PH Fitness uses PHP 8, MySQL, PDO, JavaScript, CSS, PWA, WhatsApp, and Hostinger.
Can you build a similar project for my business?
Yes. Every project is custom built, with code and accounts in the client's name. The first step is a WhatsApp conversation at +55 (33) 98465 6356 to understand what you need.
