"PCI DSS for startups: keep card data out of your systems"
The cheapest way to handle PCI DSS is to never touch card numbers. Use hosted fields or redirects and tokenization, and know what still stays on your side.
The most effective way to handle PCI DSS as a startup is to keep card data out of your systems entirely. If card numbers go straight from the customer's browser to a payment provider, and your servers only ever see a token, your compliance scope shrinks a great deal. It does not disappear, though, and the work that remains is real. Confirm your exact obligations with a qualified assessor or your acquiring bank.
What PCI DSS is, in one paragraph
PCI DSS is a security standard from the payment card industry for any organization that stores, processes or transmits cardholder data. It applies to merchants and service providers alike. The more of your own infrastructure that touches card data, the more of the standard applies to you, and the heavier the validation.
Scope reduction: how card data stays out
The goal is a flow where your systems never see the number:
- 01Customertypes into provider's field
- 02Providercaptures and tokenizes the card
- 03Your pagereceives a token only
- 04Your backendstores token, requests charge
Three building blocks make this work.
Hosted fields. The payment provider supplies the card input fields, rendered in iframes served from the provider's domain. The number never enters your page's JavaScript or your servers. Your page receives a token or a payment method ID to send to your backend.
Redirect or hosted payment page. The customer leaves your site for a payment page hosted by the provider and returns afterward. This is the simplest to build and gives you the least control over the look and feel.
Tokenization. A token is a provider-issued stand-in for a card. You store the token and use it to charge later, refund or show "card ending in" details. A leaked token is far less useful to an attacker than a card number, because it works only through your provider account. Tokenization is what lets you offer saved cards and subscriptions without holding card numbers.
Compare the options
| Option | Scope | Design control | Watch out for |
|---|---|---|---|
| Hosted fields | Small | High, branded experience | The provider's script runs on your page |
| Redirect | Smallest | Low | Less control over look and feel |
| Custom form posting to your server | Largest | Full | Heavy compliance load for your team |
Self-assessment levels at a high level
Merchants validate compliance with a self-assessment questionnaire (SAQ), and which one applies depends on how card data reaches you. Setups where payment is fully outsourced, with your site only redirecting or embedding provider-hosted fields, generally fall under the shortest questionnaires. Setups where your own page or servers handle card data fall under much longer ones. How often you must validate, and whether an external assessor is needed, depends on factors including your volume and what your acquirer requires.
What stays your responsibility
Outsourcing payment does not make you exempt. Use this as a working checklist.
The checkout page
- Strict deployment controls on the page that embeds the payment form, since attackers who modify it can try to skim card entries or redirect customers
- A content security policy and an inventory of every script on payment pages
- Tag managers, chat widgets, A/B testing and analytics kept off payment pages where you can, versions pinned, and subresource integrity used where practical
Data and secrets
- No card numbers, security codes or full payment request bodies in logs, error trackers or analytics
- Payment events logged by token or order ID, so you keep a useful audit trail
- Provider API keys in a secrets manager, restricted to minimum permissions, rotated, with test and live credentials separated
Operations
- Signature verified on every webhook, with idempotent handlers so a retried event cannot double-fulfill an order
- Limited access to the payment dashboard and checkout systems, with multi-factor authentication and change records
- The provider's compliance documentation on file, and clarity on which responsibilities are theirs and which are yours
- An incident plan for suspected card data exposure, including who to call at the provider and your acquirer
A practical sequence for a new product
- Pick a provider that offers hosted fields or a hosted page and tokenization.
- Draw the card data flow on one page. Mark every system the number could touch. The goal is "none of ours".
- Build checkout so the backend only receives tokens or payment method IDs.
- Lock down the checkout page: content security policy, script inventory, no unnecessary third parties.
- Add log scrubbing and a test that fails if card-like patterns appear in logs.
- Identify your SAQ type with your acquirer or an assessor, and write down the reasoning.
How this looks at Techdome
Our compliance work includes PCI-DSS payment compliance. In our executive-health clinic group engagement, we replaced a fragile low-code stack with an offline-first Next.js PWA that runs live payment processing through a Stripe HIPAA custom flow, working to HIPAA and PCI-DSS requirements.
For related work on lending, payments and mortgage products, see fintech and compliance.
Takeaways
- Architecture is the biggest PCI DSS lever: if card numbers never reach your systems, your scope shrinks.
- Use hosted fields or a redirect, and store only tokens.
- You still own the checkout page, third-party scripts, logging, secrets and webhook handling.
- Your SAQ type depends on how card data reaches you, so let an assessor or acquirer confirm it.
- Make "no card data in logs" a tested rule, not a habit.
Have a project like this? Talk to our engineers.
