One of the critical security bugs I found in the payment code I reviewed and each

One of the critical security bugs I found in the payment code I reviewed and eachOne of the critical security bugs I found in the payment code I reviewed and each

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ibrahim Adeyemo

• Mar 7

One of the critical security bugs I found in the payment code I reviewed and each of the bugs could have caused serious financial loss Bug #1: Trusting the payment gateway's response amount 💸

The code:

Gateway says: charge $1,000,000

System credits: $1,000,000

User actually paid: $1,000

One compromised API response = $999,000 loss.

The fix? YOUR database is the source of truth. ✅ Store amount at initialization ✅ Verify gateway matches YOUR record ✅ Credit from YOUR database, not theirs

Never trust external APIs with money.

Day 2/15 | Building Secure Payment Systems

#SoftwareEngineering #Security #FinTech

Abdul Jcg

• 19h

Day 4 of sharing my design work.

// Payment refund card When payments and refunds happen, users need clarity. They should instantly understand what happened to their money.

So this card focuses on a few simple things: • Clear refund status • Transaction amount • A quick summary of the transaction

The goal is to remove confusion and make financial interactions feel transparent and easy to track.

UI Design Figma

Denis Grasberger

pro

• 15h

I recently rescued a project that revealed a huge trap in how businesses choose tech partners.

The site's foundation was crumbling: outdated PHP and an EOL builder. The previous agency happily wanted to bill for further patches, but no one took responsibility to say: "This architecture is dead."

The client hesitated to hire me because I'm a solo freelancer. A larger agency felt like the "safer" bet. But equating headcount with security is exactly what got them into this mess.

Agencies have ticketing systems; freelancers have personal accountability. I don't bill for band-aids; I build solid foundations.

We're now migrating to a clean Webflow setup. Fixing tech debt is easy. Rebuilding trust is the real work.

Ever noticed this "safety in numbers" illusion? 👇

ownership Webflow Figma

rajesh chaudhary

• 14h

True 👍.

Ismel Figueroa

max

• 9h

Here's the first 3 things I analyze on a low-converting website: value proposition & messaging user flow & friction trust signals I quickly explain each one below 🧵