The platform behind TRSYP 3.0

Registration, teams, payments, rooming and workshop booking
for the third edition of the IEEE Tunisian RAS Student & Young Professional Congress.

Live site · How it works · Domain model · Architecture · Getting started

Contents

• About
• Features
• A quick tour
• How it works: the participant journey and the rules behind each step
• Domain model: class diagram of the database
• Key flows: sequence diagrams for registration, payment and booking
• Architecture: deployment, authentication, modules, events
• Getting started · Deployment · Engineering notes · Team

📌 About

TRSYP 3.0 took place on 16 to 18 October 2026 at Le Royal, Yasmine Hammamet, under the theme Human-Robot Symbiosis. It was organised by the IEEE INSAT Student Branch with the IEEE RAS Tunisia Section.

This repository is the congress's production web platform. It started as the event's public site and grew, between February and October 2026, into the tool participants used to sign up, form teams, pay, pick a roommate and book their workshops. The organising committee ran the other side of it (payment review, bans, visa letters, IEEE checks) from a separate admin portal that shares the same database.

400+	3	8	250+
people used the platform	team activities	months of development	commits

✨ Features

	Feature	What it does
🌐	Public site	Hero video, three-day program, speakers, workshops, venue, visa help and the three competition tracks with their spec books.
🔐	Accounts	Email/password or Google sign-in through Supabase Auth, with email verification and password reset.
🪪	IEEE membership check	Membership and RAS status are read from IEEE's member API, not from the form, and they set the fee tier.
🤖	Hybrid avatar	Every participant builds a half-human, half-robot avatar that represents them across the site.
👥	Teams	Teams for the Competition, the Technical Challenge and the Adwya × Orange Fablab Challenge, joined with a 6-character code.
💳	Payments	A fee computed from role and membership, receipt upload, and review by the treasurer.
🛏	Rooming	Double rooms formed with a join code, between two participants of the same gender.
🧑‍🏫	Workshop booking	One seat per session, capacity enforced under concurrent load, and a duty check for challenge teams.
🎚	Phase switches	Each feature opens and closes on its own soon / open / closed window, set from environment variables.

📸 A quick tour

Public pages are captured from the running app. Signed-in pages use a demo account and sample data.

Home

The landing page opens on the congress's hero video, dates and a countdown.

Dashboard

Everything a participant needs on one page: profile and avatar, fee and payment status, team and invite code.

Payment

The full fee table with the participant's own fee highlighted, the bank details and the receipt upload.

Workshop booking

Live seat counts, one seat per session, and a note telling challenge teams whether they are covered.

Rooming

Create a double room and send its code to a roommate, or join theirs.

On a phone

    

🧭 How it works

The participant journey

A participant goes through the same steps in order. Each step after the profile is optional and has its own registration window.

flowchart LR
    A["Create account<br/>email or Google"] --> B["Verify email"]
    B --> C["Fill participant profile<br/>phone, gender, career stage,<br/>student branch, IEEE number"]
    C --> D["IEEE check<br/>runs in the background"]
    C --> E["Build avatar"]
    E --> F{{"Dashboard"}}
    F --> G["Create or join teams"]
    F --> H["Pay the fee"]
    F --> I["Form a room"]
    H -- "payment approved" --> J["Book workshops"]

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The profile is the only required step. Once it exists, the participant lands on the dashboard and everything else is done from there. The avatar is required before the dashboard opens, because it is how participants appear to each other in teams and rooms.

1. IEEE membership

Participants don't declare their own membership. They give their IEEE member number (if they have one), and the backend asks IEEE's member API who they are.

• Lookup key. The member number is used first. The account email is the fallback, and only once the participant has verified that email.
• Standing. IEEE's status is mapped to four standings: Active is a member, Applicant also counts as a member (usually waiting for payment), any other past status is lapsed, and no record is not a member.
• RAS. A participant counts as RAS only if they are an active member and IEEE lists the RAS society (MEMRA024) among their societies.
• Student or Young Professional. IEEE's grade is ignored on purpose: this is the participant's own answer.
• When it runs. Right after registration, whenever the member number changes, on request from the dashboard, and in a background sweep every 5 minutes that rechecks unverified or outdated participants, 20 at a time. A failed IEEE call writes nothing and is retried later.
• Until the answer arrives, a new participant is priced as a non-member.

The admin portal writes to the same ieee_verifications table. When it records a result, the backend applies it to the participant on its next pass, so both sides always agree on how someone is priced.

2. Fees

The fee depends on two things: the participant's role (what they take part in) and their tier (their IEEE membership).

Role \ Tier	IEEE RAS member	IEEE member	Non-IEEE
Visitor, attending without a team	170 TND	175 TND	185 TND
Challenger, on a Competition or Technical Challenge team	175 TND	180 TND	190 TND
Fablab participant, on a Fablab team	100 TND	100 TND	100 TND

• Role precedence. Fablab wins over Challenger, which wins over Visitor. A participant on both a Fablab team and a Competition team pays the Fablab fee.
• Selection. Only teams that passed the selection phase (Team.selected) count. A team that was not selected no longer makes its members challengers.
• Override. An agreed exception (Participant.feeOverride) replaces the table for that one person.
• Snapshot. When a receipt is submitted, the fee at that moment is stored with it (amountSnapshot), so the treasurer reviews the amount the participant actually saw, even if their role or tier changed afterwards.

The table lives in backend/.../registration/domain/fees.ts and is mirrored in lib/fees.ts, so the dashboard can update the fee the moment someone joins a team, without waiting for the server.

3. Teams

Activity	Team size	Who can enter
Competition	3 to 6	Everyone
Technical Challenge	2 to 6	Everyone
Adwya × Orange Fablab Challenge	2 to 4	IEEE members who are also RAS members

• The creator becomes the leader and gets a unique 6-character join code to share.
• A participant can be in at most one team per activity, but can be in one team of each. This is a unique index on (participant, activity) in team_memberships, not just a check in the code.
• A leader leads at most one team per activity, also enforced by a unique index.
• Members can leave. The leader cannot leave: they can remove members or disband the team, so a team is never left without a leader.
• A team cannot grow past the size its leader chose.
• Fablab teams also pick an axis (sample preparation, or weighing and dosing) and the leader submits the concept dossier from the dashboard, during its own submission window.

4. Payments

Payment is by bank transfer. The participant transfers the fee and uploads the receipt. A committee member reviews it.

stateDiagram-v2
    direction LR
    [*] --> NotPaid
    NotPaid --> Pending: receipt uploaded
    Pending --> Approved: treasurer approves
    Pending --> Rejected: treasurer rejects, with a reason
    Rejected --> Pending: new receipt uploaded
    NotPaid --> Approved: cash recorded by an admin
    Approved --> [*]

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• Participant.paid is the single source of truth. Only approving a proof sets it, and rejecting a proof always clears it, so a participant can never see "paid" next to a rejected receipt.
• Only one proof can be pending at a time, and none can be sent once the payment is confirmed.
• Rejected proofs are kept, so the next submission can be compared with the one that was turned down.
• Cash has no receipt: the admin who receives it records it, and it is stored already approved.
• After approval, the treasurer records how the money actually arrived (bank transfer, internal fund or cash).
• Once a participant has paid, their profile is locked and their account cannot be deleted without a refund first.

5. Rooming

• Every room is a double. The creator becomes the owner and gets a 6-character code to send to their roommate.
• The room takes the owner's gender, and only a participant of the same gender can join. A participant cannot change their gender while they are in a room, so this never goes out of date.
• A participant is in at most one room.
• Joining locks the room row for the transaction, so two people racing for the last spot cannot both get it.
• The owner can remove the roommate or disband the room. Deleting the room frees the roommate automatically.

6. Workshops

Day 3 has two workshop sessions. Workshops in the same session run in parallel.

• A participant gets one seat per session, enforced by a unique index on (participant, session).
• Bookings are final: no cancelling, no switching.
• Booking needs a confirmed payment (or a payment waiver granted by the committee). Banned participants cannot book.
• Team duty. Each selected Technical Challenge team needs at least one member in a workshop, in either session, or its student branch loses points (WORKSHOP_SB_PENALTY). The team sees whether it is covered. This rule is reported to the organisers, not enforced by the booking.
• How capacity holds under a rush is explained in Key flows.

7. Registration windows

Every feature reads its own window from an environment variable, so the committee could open and close each step without a code change.

stateDiagram-v2
    direction LR
    [*] --> soon
    soon --> open
    open --> closed
    closed --> open: reopened

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• soon and closed both block creating and joining. They only change the message shown.
• In closed, existing teams stay visible and manageable. Nobody can create or join new ones.

🗂 Domain model

The database is PostgreSQL on Supabase, described in backend/prisma/schema.prisma and versioned with Prisma migrations. Participant is the centre of the model: everything a participant does hangs off it. The two diagrams below show the models behind the features above, with their main fields.

Identity and membership

Who someone is: their account, their participant profile, what IEEE says about them, and, for international participants, their travel and visa details. Admin is separate: committee members are not participants.

classDiagram
    class User {
        +String id
        +String email
        +String name
        +String lastName
        +String supabaseId
        +Json avatar
    }

    class Participant {
        +String id
        +Int ieeeId
        +String phone
        +String gender
        +ParticipantType participantType
        +CareerStage careerStage
        +Boolean isRas
        +SB sb
        +Country country
        +Boolean paid
        +Boolean banned
        +Int feeOverride
    }

    class IeeeVerification {
        +IeeeCheckStatus status
        +String memberStatus
        +String[] societies
        +String matchedBy
        +DateTime checkedAt
        +String checkedBy
    }

    class InternationalInfo {
        +String countryOfResidence
        +String affiliation
        +DateTime expectedArrivalDate
        +Boolean requiresVisaLetter
    }

    class VisaApplication {
        +String passportNumber
        +VisaStatus status
    }

    class Admin {
        +String email
        +Position position
        +String supabaseId
    }

    User "1" -- "0..1" Participant : has profile
    Participant "1" -- "0..1" IeeeVerification : checked by IEEE
    Participant "1" -- "0..1" InternationalInfo : travels from abroad
    InternationalInfo "1" -- "0..1" VisaApplication : needs a visa

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Activities

What a participant takes part in: teams, payment, room and workshop seats.

classDiagram
    class Participant {
        +String id
        +Boolean paid
        +Boolean banned
    }

    class Team {
        +String code
        +String name
        +Int size
        +TeamActivity activity
        +FablabAxis axis
        +String submissionUrl
        +Boolean selected
    }

    class TeamMembership {
        +TeamActivity activity
        +DateTime createdAt
    }

    class PaymentProof {
        +PaymentMethod method
        +PaymentProofStatus status
        +Int amountSnapshot
        +String storagePath
        +PaymentType paymentType
        +String rejectionReason
    }

    class Room {
        +String code
        +String gender
    }

    class Workshop {
        +String id
        +String title
        +Int session
        +String startTime
        +Int capacity
    }

    class WorkshopBooking {
        +Int session
        +DateTime createdAt
    }

    class WorkshopPaymentWaiver

    Participant "1" -- "*" TeamMembership : joins
    TeamMembership "*" -- "1" Team
    Participant "1" -- "*" Team : leads
    Participant "1" -- "*" PaymentProof : submits
    Participant "1..2" -- "0..1" Room : lives in
    Participant "1" -- "0..1" Room : owns
    Participant "1" -- "*" WorkshopBooking : books
    WorkshopBooking "*" -- "1" Workshop
    Participant "1" -- "0..1" WorkshopPaymentWaiver : may book unpaid

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Enumerations

Enum	Values
ParticipantType	NonIEEE, Student, YoungProfessional
CareerStage	Student, YoungProfessional
TeamActivity	COMPETITION, CHALLENGE, FABLAB
FablabAxis	SAMPLE_PREPARATION, WEIGHING_DOSING
IeeeCheckStatus	VERIFIED, MISMATCH, INACTIVE, NOT_FOUND
PaymentMethod	BANK_TRANSFER, D17, FLOUCI, CASH (only bank transfer is offered in the UI)
PaymentType	BANK_TRANSFER, INTERNAL_FUND, CASH
PaymentProofStatus	PENDING, APPROVED, REJECTED
VisaStatus	Pending, Approved, Rejected, LetterSent

Rules held by the database itself, so they hold even under concurrent requests:

Constraint	Rule
team_memberships (participant_id, activity) unique	One team per activity per participant
teams (leader_id, activity) unique	One led team per activity
workshop_bookings (participant_id, session) unique	One workshop seat per session
rooms.owner_id unique, participants.room_id single column	One owned room, one room per participant
participants.ieee_id, participants.phone unique	No two profiles with the same IEEE number or phone
TeamMembership.activity copied from Team.activity	Makes the first rule a plain unique index (a team's activity never changes)
WorkshopBooking.session copied from Workshop.session	Same idea for one seat per session

🔁 Key flows

Sign-up and registration

sequenceDiagram
    autonumber
    actor P as Participant
    participant W as Next.js app
    participant SA as Supabase Auth
    participant API as NestJS API
    participant DB as PostgreSQL
    participant IEEE as IEEE member API

    P->>W: Sign up (email or Google)
    W->>SA: signUp / OAuth
    SA->>DB: auth.users insert
    Note over DB: trigger on_auth_user_created<br/>creates the public users row
    SA-->>P: verification email
    P->>W: Fill participant profile
    W->>API: POST /registration (Bearer JWT)
    API->>API: verify JWT, resolve users row
    API->>DB: create participant, priced as NonIEEE
    API-->>W: 201 participant
    API-)API: event participant.registered
    API->>IEEE: look up member number, else verified email
    IEEE-->>API: status and societies
    API->>DB: save ieee_verification, set participantType and isRas
    W->>API: GET /registration/profile
    API-->>W: profile with fee and IEEE standing

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The IEEE check happens after the response, through an internal event, so registration never waits on IEEE's API and never fails because of it.

Payment review

sequenceDiagram
    autonumber
    actor P as Participant
    participant API as NestJS API
    participant ST as Supabase Storage<br/>(private bucket)
    participant DB as PostgreSQL
    actor T as Treasurer<br/>(admin portal)

    P->>API: POST /payment/proof (receipt)
    API->>API: window open? not banned, not paid,<br/>no other proof pending?
    API->>DB: insert proof PENDING with amountSnapshot
    API->>ST: upload receipt, keyed by proof id
    Note over API,ST: failed upload rolls the row back
    API-->>P: proof PENDING
    T->>API: GET /payment/admin/proofs (oldest first)
    T->>API: GET /payment/proof/:id/file
    API->>ST: create signed URL (60 s)
    API-->>T: short-lived link
    alt approve
        T->>API: POST /payment/admin/proofs/:id/approve
        API->>DB: proof APPROVED, participant.paid = true
    else reject
        T->>API: POST /payment/admin/proofs/:id/reject (reason)
        API->>DB: proof REJECTED, participant.paid = false
    end
    P->>API: GET /payment/proof/me
    API-->>P: status, and the reason if rejected

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Workshop booking under load

When booking opens, many people try to book the same popular workshop within seconds.

sequenceDiagram
    autonumber
    actor A as Participant A
    actor B as Participant B
    participant API as NestJS API
    participant DB as PostgreSQL

    par
        A->>API: POST /workshops/pitching/booking
    and
        B->>API: POST /workshops/pitching/booking
    end
    API->>DB: BEGIN, SELECT workshop FOR UPDATE (A)
    API->>DB: BEGIN, SELECT workshop FOR UPDATE (B)
    Note over DB: B waits for A's lock
    API->>DB: count seats, insert booking A, COMMIT
    API-->>A: 201 seat booked
    Note over DB: lock released, B reads the final count
    API->>DB: count seats: full, ROLLBACK
    API-->>B: 403 This workshop is full

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• Every booking locks exactly one row, the workshop, so bookings cannot deadlock.
• The unique (participant, session) index catches a double booking even if two requests from the same person arrive at once.
• Transaction timeouts are raised above Prisma's defaults so the queue drains during a rush. If it still times out, the participant is asked to try again in a moment instead of getting an error.

🏗 Architecture

Deployment

One Docker image runs both applications in a single Render web service. Next.js listens on the public port and proxies /api/* and /health to NestJS, so the browser only ever talks to one origin.

flowchart LR
    B([Browser])

    subgraph R["Render web service · one Docker container"]
        N["Next.js 16<br/>public PORT"]
        A["NestJS API<br/>:3001"]
        N -- "/api/*, /health" --> A
    end

    SA[("Supabase Auth")]
    DB[("Supabase PostgreSQL")]
    ST[("Supabase Storage<br/>receipts")]
    IEEE["IEEE member API"]
    AP["Admin portal<br/>(separate app)"]

    B --> N
    B -. "sign-in, session JWT" .-> SA
    A -- "verifies JWT" --> SA
    A -- "Prisma 7" --> DB
    A -- "service role" --> ST
    A -- "membership checks" --> IEEE
    AP -.-> DB

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Authentication and authorisation

• Sign-in is Supabase's job. The browser signs in with Supabase Auth and sends the session's access token as a Bearer header on every API call.
• The API verifies the token itself. ES256 tokens are checked against Supabase's public keys (JWKS, cached), and legacy HS256 tokens against the project secret. Expired tokens are refused.
• From Supabase user to database user. A database trigger creates the users row when someone signs up. The JWT strategy then finds that row from the token's subject, and recreates it if it is ever missing, so a valid token is never locked out.
• Admins are whoever is listed in the admins table. Admin routes check that table, not a claim in the token.
• Receipts are in a private storage bucket that only the API can reach, with the service-role key. Reviewers get a signed link that expires after 60 seconds.
• Input is validated with class-validator DTOs; unknown fields are stripped before they reach a service.
• Abuse. Helmet sets security headers, and a global rate limit allows 50 requests per minute per client.

Backend modules

The API is a modular monolith: one NestJS app, one folder per domain, each with its own controller, service, DTOs and domain rules.

Module	Responsibility
auth	Supabase JWT strategy, user sync, profile and avatar, admin guard
registration	Participant profile, fee rules, teams for the three activities, Fablab submission, bans
ieee	IEEE member API client, membership verification and the background sweep
payment	Receipt upload and storage, review queue, cash payments
rooming	Double rooms with join codes
workshop	Day-3 workshop booking and team workshop duty
visa	Visa applications for international participants
admin	Admin accounts

Modules react to each other through domain events (@nestjs/event-emitter) instead of calling each other for side effects. The registration module announces what happened, and the ieee module listens:

Event	Emitted when	Listener
participant.registered	A participant profile is created	ieee runs the first membership check
participant.ieee_details_changed	The member number changes	ieee checks again

The payment module also emits payment.proof.submitted and payment.status.updated, and registration emits participant.paid. Nothing listens to them yet: they are the hook for notifications.

Frontend

• Next.js App Router. The dashboard talks to the API through a typed client in lib/api/, one service per backend module, with types that mirror the API's responses.
• State lives in small Zustand stores (lib/store/): the auth session, the participant's registration, and their teams.
• Windows are read in lib/config.ts from NEXT_PUBLIC_* variables, so a closed feature is hidden in the UI as well as refused by the API.

Tech stack

Layer	Tools
Frontend	Next.js 16 (App Router), React 19, TypeScript, Zustand, Motion, Avataaars
Backend	NestJS 10, Prisma 7 with the pg adapter, class-validator, Joi config validation, Passport JWT, @nestjs/event-emitter
Data and auth	Supabase PostgreSQL, Supabase Auth (email and Google), Supabase Storage
Security	Helmet, @nestjs/throttler, JWKS verification, admin guard
API docs	Swagger at /api/docs outside production
Tests	Jest, with unit tests for fees, IEEE membership, payments, registration, rooming and workshops
Delivery	Multi-stage Dockerfile, Render, GitHub Actions deploy hook

Project structure

.
├── app/                 Next.js routes (public pages, /register, /dashboard)
├── components/          Page and section components
├── lib/
│   ├── api/             Typed client for every backend endpoint
│   ├── store/           Zustand stores (auth, registration, teams)
│   ├── supabase/        Browser Supabase client and email callbacks
│   ├── fees.ts          Fee table, mirrored from the backend
│   └── config.ts        Runtime config and registration windows
├── backend/
│   ├── prisma/          Schema, migrations, seed
│   └── src/
│       ├── common/      Guards, decorators, pipes, event names
│       └── modules/     One folder per domain
│           └── <module>/
│               ├── controller/   HTTP routes
│               ├── service/      Use cases and transactions
│               ├── domain/       Pure rules (fees, IEEE mapping)
│               └── dto/          Validated request and response shapes
├── public/              Images, hero video, partner and speaker photos
├── scripts/             Image optimisation, production start script
├── Dockerfile           Builds both apps into one image
└── render.yaml          Render service definition

🚀 Getting started

Requires Node.js 20 or newer and a Supabase project.

git clone https://github.com/IEEE-INSAT/TRSYP3.0.git
cd TRSYP3.0
cp .env.example .env        # fill in the Supabase values

Start the API:

npm --prefix backend ci
cd backend
npx prisma generate
npm run start:dev

Start the frontend in another terminal:

npm ci
npm run dev

The frontend runs at http://localhost:3000 and the API at http://localhost:3001. Both applications and Prisma read the single root .env file.

Configuration

.env.example documents every variable. The ones you will touch most are the windows:

Variable	Values	Controls
NEXT_PUBLIC_PARTICIPANT_REGISTRATION_OPEN	true / false	Participant sign-up
NEXT_PUBLIC_COMPETITION_PHASE, COMPETITION_REGISTRATION_PHASE	soon / open / closed	Competition teams
NEXT_PUBLIC_CHALLENGE_PHASE, CHALLENGE_REGISTRATION_PHASE	soon / open / closed	Technical Challenge teams
NEXT_PUBLIC_FABLAB_PHASE, FABLAB_REGISTRATION_PHASE	soon / open / closed	Fablab teams
NEXT_PUBLIC_FABLAB_SUBMISSION_PHASE, FABLAB_SUBMISSION_PHASE	soon / open / closed	Fablab concept submission
NEXT_PUBLIC_ROOMING_PHASE, ROOMING_PHASE	soon / open / closed	Rooming
WORKSHOP_BOOKING_PHASE	soon / open / closed	Workshop booking
WORKSHOP_SB_PENALTY	number	Points a student branch loses when its team skips workshops
PAYMENT_PROOF_OPEN	true / false	Receipt upload (read per request, no rebuild)
IEEE_CLIENT_ID, IEEE_CLIENT_SECRET	secret	IEEE membership checks (without them, everyone is priced as a non-member)

Keep each NEXT_PUBLIC_* window aligned with its backend twin. NEXT_PUBLIC_* values are compiled into the browser bundle, so changing one needs a frontend rebuild.

Checks

cd backend
npm run build
npm test -- --runInBand

cd ..
npm run typecheck
npm run lint
npm run build

☁️ Deployment

The root Dockerfile builds both applications. Next.js listens on Render's public PORT; NestJS listens internally on port 3001. docker-compose.yml gives the same topology for local container testing:

docker compose up --build    # http://localhost:3000

render.yaml defines the single Docker service. Provide every variable marked sync: false before deploying. Every push to main triggers the Render deploy hook through .github/workflows/deploy-render.yml.

Supabase authentication emails are configured in the Supabase dashboard, not in Render. Set the public frontend as the Auth Site URL and allow:

https://rtc.ieee.tn/verify-email/
https://rtc.ieee.tn/reset-password/

For local development, also add this under Supabase Dashboard → Authentication → URL Configuration → Redirect URLs:

http://localhost:3000/**

Without it, Supabase ignores the localhost redirectTo the app asks for and falls back to the production Site URL.

🧠 Engineering notes

Decisions that mattered once real traffic arrived:

• Let the database hold the rules. "One team per activity", "one seat per session" and "one room per person" are unique indexes, not if statements. Two requests arriving at the same millisecond cannot both pass.
• Lock one row, never two. Workshop booking and room joining each lock a single row, which makes them safe under concurrency without any risk of deadlock.
• Fees from the source. The tier comes from IEEE's records, so nobody gets the cheaper fee by ticking a box, and the admin portal and the API price everyone the same way.
• Slow dependencies off the request path. The IEEE check runs from an event and a background sweep, so IEEE being slow or down never blocks a registration.
• One source of truth for "paid". Receipts are an audit trail. Only Participant.paid says whether someone has paid, and only approval changes it.
• Switches without a rebuild. Backend windows such as PAYMENT_PROOF_OPEN are read per request.
• One origin. Next proxies the API, so there is no CORS to manage in production and one Render service hosts everything.
• Images ready ahead of time. On-the-fly image optimisation was too slow on Render's free instance, so images are converted to WebP with scripts/optimize-images.mjs before they are committed.

👥 Team

Built by the IEEE INSAT Student Branch web team:

Makki Aloulou

Mohamed Amine Achour

Yassine Kolsi

_{IEEE INSAT Student Branch × IEEE RAS Tunisia Section · TRSYP 3.0 · 2026}