Reyhan Rizqi

Problem

A physical gaming store needed an online catalogue, checkout, and an admin panel its staff could run without a developer.

My role

Developer. Built the storefront, admin panel, serverless API, and Midtrans checkout.

Key decisions

• Midtrans Snap is embedded in the page instead of using a redirect, because a redirect flow had broken checkout in an earlier project when in-app browsers intercepted it.
• Payment webhooks are signature-verified, and stock is decremented only on the pending to paid transition, so duplicate notifications cannot decrement it twice.
• libSQL locally and Turso in production, switched by environment variables, so the same code runs in both.
• A sitemap endpoint and one canonical www address, so search engines see a single site.

Outcome

Live at libertygame.id. Handed over on 13 August 2026 with 76 products (58 games, 10 consoles, 8 accessories), 15 public pages, 5 blog posts, and the admin panel.

Problem

Most health apps assume a confident smartphone user. Detakku is built so parents and grandparents can use it too: large text, one clear action per screen, and an AI buddy that answers in plain language.

My role

Developer. Built the Expo app and its tRPC and Drizzle backend.

Key decisions

• Caregiver mode: a family member can be linked to a relative through an invite and receive alerts.
• Bilingual in English and Indonesian.
• Credit-based AI usage, billed with Stripe on the web. The first native release is consumption-only, with free credits and no purchase buttons.
• The repo has 182 test files, including account deletion and payment replay cases.

Outcome

Live at detakku.com with an Android build to download. iOS and Android store submissions are prepared, with a release runbook.

• Every transfer posts one debit and one credit, and is rejected in code if they do not balance.
• Accounts are locked in account-number order to reduce deadlock risk.
• An Idempotency-Key header makes client retries safe: a repeat returns 200 with replayed: true and posts nothing.
• Rule-based fraud screening and a daily limit run before money moves.
• Events go to an outbox table in the same transaction, with an optional Kafka relay.

create or replace function public.fulfill_paid_order() returns trigger language plpgsql security definer set search_path = '' as $$
declare entitlement_expiry timestamptz;
begin
  if new.status = 'paid' and old.status is distinct from 'paid' then
    entitlement_expiry := case new.plan_id when 'weekly' then now() + interval '7 days' when 'monthly' then now() + interval '1 month' else null end;
    insert into public.entitlements (user_id, email, order_id, series_id, expires_at)
    values (new.user_id, new.email, new.id, new.series_id, entitlement_expiry) on conflict (order_id) do nothing;
    if new.referrer_profile_id is not null and new.referrer_profile_id is distinct from new.user_id then
      insert into public.affiliate_commissions (partner_id, order_id, amount, status)
      values (new.referrer_profile_id, new.id, floor(new.amount * 0.20), 'available') on conflict (order_id) do nothing;
    end if;
  end if;
  return new;
end;
$$;
create trigger on_order_paid after update of status on public.orders for each row execute procedure public.fulfill_paid_order();