Get paid online — without the checkout headaches.
I'm Pablo, a senior backend engineer. I add, fix and upgrade payments for products with their own checkout or backend — SaaS, marketplaces, custom-built stores and apps — with Stripe, PayPal, Square, Authorize.net and more. Clear scope, written proposal, working in your timezone.
What I can do for you
Payments
Add payments to your site or app
One-time payments and saved cards with Stripe, PayPal, Square or Authorize.net, plus Apple Pay and Google Pay. Webhooks, receipts and refunds done right from day one.
Fix a broken or declining checkout
Payments failing, legitimate cards getting declined, duplicate charges, webhooks that never arrive, 3DS / SCA challenges that kill conversion. I find the cause and fix it.
Subscriptions & recurring billing
Plans, trials, renewals, upgrades and downgrades, failed-payment retries and a customer billing portal — so recurring revenue actually recurs.
Switch or add a payment provider
Move to a better gateway or add a second one without downtime, keeping saved cards where the providers support it.
Problems I've already solved
Card approval rates back above 90%
Approvals in key international markets had collapsed. I implemented 3DS2 correctly, enriched the data sent to card issuers and fixed recurring-payment flags. Hundreds of thousands of dollars in legitimate sales stopped being declined.
10+ payment providers in one checkout
Cards, Apple Pay, Google Pay, buy-now-pay-later, bank payments and local methods across North America, Europe and Asia, unified behind a single payment layer.
How it works
Tell me what is going on
Two minutes with the form below. No sales pitch.
Short call
A free 20-minute call to understand your setup and goals.
Written proposal in 48h
Scope, price and timeline in writing. For larger or undocumented systems, a short paid diagnostic comes first.
Build, test, go live
Tested before anything reaches your customers, then launched, with a short handoff doc.
What you get
- A senior engineer, directly — no agency layers or account managers.
- Clear written English, async-friendly, 1–2 hours ahead of US Eastern.
- Card data never touches your server: I use provider-hosted fields and checkouts to keep your PCI scope minimal.
- The code and the accounts are yours from day one.
FAQ
What platforms do you work with?
Custom-built websites, apps and APIs — mainly PHP / Laravel and Node.js / TypeScript, with MySQL, PostgreSQL or MongoDB.
I use Shopify, Wix or Squarespace. Do I need you?
Probably not — their built-in payments are usually the right answer. I help products with their own checkout or backend: SaaS, marketplaces, custom-built stores and apps.
How much does it cost?
After the call you get a written proposal with scope and price. A well-defined integration gets a fixed price and usually takes days, not months. If the problem is unclear (for example, unexplained declines), we start with a short paid diagnostic.
How do contracts and payment work?
Written scope, invoice in USD, a deposit to start and the rest on delivery. Happy to sign an NDA.
What size of projects do you take?
Well-scoped projects with part-time dedication: an integration, a fix, an upgrade, or a rebuild split into phases. I am not available as a full-time contractor or to join a team indefinitely.
Are you available right now?
I take a limited number of projects at a time, so I can give each one proper attention. Send the form and I will tell you honestly when I can start.
Tell me about your project
I reply within one business day.