Building a FinTech App with Custom Payment Bins: A Secure, Scalable Approach
October 1, 2025How ‘Cherry Picking Our Own Fake Bin’ Inspired the Next Generation of Real Estate Software
October 1, 2025As a VC, I look for signals of technical excellence in a startup’s DNA. This one issue? It’s a red flag I can’t ignore — and it directly impacts how I value a company.
When “Fake Bin” Decisions Signal Startup Health
In venture capital, technical due diligence covers the usual suspects: architecture, scalability, security, and tech stack. But one of the most telling signs of a startup’s long-term technical health? How the team treats their “fake bin.”
Think of the fake bin as the digital equivalent of a junk drawer — where shortcuts, quick fixes, and “we’ll fix it later” code collect. It’s where duct-tape solutions live: temporary APIs, manual data scripts, hardcoded passwords, or entire services built on outdated tech.
Just like that coin collector who kept a historically significant reproduction among worthless fakes, I see founders doing the same. They treat some parts of their system as sacred “authentic” code, while letting others rot in technical debt. They hope no one notices.
Here’s the thing: VCs notice the fake bin. And it tells us everything about a team’s discipline and scalability.
Why the “Fake Bin” Exists in Early-Stage Startups
Startups move fast. At the seed stage, speed trumps perfection. Founders and engineers make smart trade-offs — some parts of the system get proper architecture, while others get hacked together to ship fast.
The fake bin is where these compromises hide. At first, it’s fine. But over time? It becomes a ticking time bomb — especially when investors or acquirers start poking around.
Unlike the coin collector who proudly showed off their well-made copy, a startup that brags about their fake bin has a problem: they don’t know the difference between moving fast and building to last.
How the Fake Bin Impacts Valuation at Seed and Series A
When I evaluate a Series A startup, I don’t just look at growth numbers. I look at technical leverage — how much output a team gets for every unit of technical debt. High-leverage teams scale efficiently. Low-leverage teams? They’re drowning in fires.
Seed Stage: The Signal of Strategic Discipline
At seed, I expect a *small* fake bin. What matters is awareness and a plan to fix it. I watch for three things:
- Transparency: Does the CTO have a documented tech debt log?
- Prioritization: Are they actively scheduling time to refactor?
- Automation: Do they use CI/CD, infrastructure-as-code, and monitoring?
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I once backed a fintech startup with a “fake” reconciliation engine — built in a weekend with a spreadsheet parser and cron job. But the CTO had already scheduled a 3-week sprint to replace it with a proper event-sourced pipeline. That kind of discipline? It signaled a team that understood the difference between speed and scale.
Series A: The Scalability Test
By Series A, I want the fake bin to be under 10% of the codebase — and shrinking. If it’s still growing or contains core components, I’m out. Why?
At this stage, you’re not validating product-market fit anymore. You’re scaling, integrating, and facing audits. A bloated fake bin means:
- Longer onboarding for new customers
- Higher operational costs
- More bugs and outages
- A harder time attracting top engineers
I passed on a SaaS company with 80% user growth because their billing system was Python scripts glued together with os.system() calls. “It works,” the CTO said. I said, “It won’t scale.” Months later, they had to delay a major contract because they couldn’t audit usage data. Their valuation dropped 30%.
What VCs Look for in a Tech Stack (Beyond the Hype)
Founders love to pitch their stack like it’s a luxury car: “Built on React, Kubernetes, AWS Lambda — it’s cloud-native!” But I look past the buzzwords.
The Stack Audit: 5 Red Flags in the Fake Bin
Here’s what I notice during due diligence:
- Manual scripts running in production
Example: A nightly cron job syncing databases. This should be ak8s CronJobor scheduled Lambda with logging and alerts. - Hardcoded secrets
Example: A.envfile in GitHub (yes, I check). UseAWS Secrets ManagerorHashicorp Vault. - Monolithic functions
Example: A 500-lineprocess_order()function handling everything. Break it into smaller, focused functions. - No observability in critical paths
Example: No logging in the payment flow. UseOpenTelemetryorDatadogto monitor errors. - “We’ll migrate it later” services
Example: A legacy PHP user service in a Go app. If it handles auth or billing, it’s a time bomb.
Code Snippet: Fake Bin vs. Clean Architecture
I saw this in a seed-stage startup:
// FAKE BIN: Temporary user sync script (manual run, no logs)
const users = parseCSV('users.csv');
users.forEach(user => {
fetch('https://api.acme.com/users', {
method: 'POST',
body: JSON.stringify(user)
}); // No error handling, no retry
});
Versus the scalable version:
// CLEAN: Event-driven, retryable, observable
export async function handleUserImport(event: UserImportEvent): Promise
const { userId, csvUrl } = event;
try {
const users = await downloadAndParseCSV(csvUrl);
for (const user of users) {
await auditLog('import:start', { userId, email: user.email });
const result = await UserService.create(user, {
retries: 3,
timeout: 5000
});
await auditLog('import:complete', { userId, status: result.status });
}
} catch (error) {
await alertTeam('User import failed', error);
throw error;
}
}
The first script works — but it’s fragile and invisible. The second? It’s investor-ready: observable, auditable, and built for scale.
How to Clean Your Fake Bin Before Raise
If you’re a founder or CTO, here’s how to turn your fake bin into an asset:
1. Conduct a “Tech Debt Audit”
Use tools like SonarQube, CodeClimate, or Semgrep to find technical debt. Categorize it:
- Critical (security, scalability risks)
- High (usability, maintainability)
- Low (cosmetic issues)
2. Create a “Tech Debt Sprint”
Block 2–4 weeks pre-Series A to tackle top priorities. Show investors you’re proactive, not reactive.
3. Document and Share
Add a “Technical Debt” section to your pitch deck. Explain what was in the bin, what you fixed, and what’s left. This builds credibility — not weakness.
Conclusion: The Fake Bin Is a Mirror of Your Team’s DNA
VCs don’t just fund ideas — we fund teams that can execute at scale. The fake bin isn’t just about code. It’s about discipline, foresight, and long-term thinking.
A team that keeps its fakes hidden might look clever short-term. But a team that identifies, documents, and eliminates its fakes? That’s the team worth betting on.
At seed, I’ll tolerate a little mess. But at Series A, I want a clean house. Because in tech, how you handle your fake bin today decides your valuation tomorrow.
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