Why We Refused to Build a Custodial Bitcoin Wallet
Why self custody matters even for a fintech product?
We had everything in place to build a custodial Bitcoin wallet. Licensed partners in Estonia. Regulatory framework. It would have been easier and more profitable.
We chose not to.
I quit my job in Estonia in 2022, moved to India, and started building Bringin because moving money between territories was hell. Waiting days for funds defeated the point of storing value outside custodied bank accounts.
Bitcoin works anywhere. But we need bridges to fiat rails for merchants and bills.
Three years later, we’re launching Europe’s most complete Bitcoin app. Self-custodial Lightning wallet combined with euro banking services. But the path here taught me something most Bitcoin users don’t understand.
The Choice I Didn’t Want to Make
When Stricter regulations arrived in Europe, the Lightning ecosystem split into two ways.
Many companies took the custodial route. Compliance achieved, but users lost sovereignty. Every payment goes through the provider’s node. Transactions monitored, analysed, and blocked when needed.
The other path: users run their own Lightning node. Full control over channels, liquidity, and key security. Even advanced bitcoiners face constant rebalancing, downtime, and complexity.
Companies with VC backing hired compliance departments to fast-track CASP licenses. Custodial made sense for them. European bitcoiners faced an unwanted choice: regulatory safety or financial sovereignty.
We had all the infrastructure to build a custodial. Licensed partners in Estonia. Regulatory framework in place. It would have been easier and more profitable.
But custodial Bitcoin services aren’t Bitcoin. They’re crypto-themed banks.
What Custodial Actually Means
Here’s what most users don’t realise: when you use a custodial Bitcoin service in Europe, specialised blockchain analysis companies score every transaction you make. Source addresses, destination addresses, deciding what’s “safe” or “risky.”
If their system flags something, you can be stopped from sending YOUR funds to an address YOU choose.
You need permission to use your own money.
Your “Bitcoin balance” is a database entry. An IOU from the provider. You’re trusting them to keep accurate records, maintain security, stay operational, and honour withdrawals when you want them.
All transaction data must be recorded and stored. Even privacy-focused providers have no choice = it’s legally required. They know where you paid, when, and what for.
This is exactly what a bank does. We’ve been trusting banks for years.
Custodial Bitcoin wallets are just banks with better marketing.
Why We Chose the Hard Path
At Bringin, we made a deliberate choice. Yes, we provide regulated euro services through licensed partners. That’s the reality of interfacing with traditional finance in Europe. We require KYC for fiat services.
But for Bitcoin? We refuse to take custody.
We started with Greenlight—remote Lightning nodes with user keys encrypted on devices. It proved clunky. That’s why Relai sunsetted their Lightning integration.
We moved to the Breez SDK for non-custodial control with a managed backend. Problems emerged during testing. Node wake-ups took 20-30 seconds. Payments failed when the app closed. Non-custodial Lightning sounded good but was fragile in daily use.
Months of optimisation proved one thing: Lightning assumes constant connectivity. That’s incompatible with how people use mobile wallets.
I reframed the question: Do users really need to run a Lightning node to benefit from Lightning payments?
The Solution We Built
We use submarine swaps—atomic conversions between Lightning and Liquid, Bitcoin’s federated sidechain. Breez SDK manages Lightning interactions and handles swaps without node management. Standard BIP-39 seed phrases give users full control and wallet portability.
When you receive a Lightning payment in Bringin, it converts to L-BTC and lands in your self-custody wallet. Payment completes even if the app is closed. No nodes to manage. No channels to rebalance. Total privacy. You never give up your keys.
We provide non-KYC Bitcoin and Lightning wallet access. Direct interaction with the Bitcoin network. Minimal Lightning fees with no profit extraction from Bitcoin transactions. Complete user control over private keys.
We only profit on euro swaps—1% flat fee when you choose to interface with traditional finance.
Engineers, Not Bankers
It took three years because we refused the easier path. Our first version of the product is a simple webapp to connect Banks and users’ own wallets, and now to a mobile app that can securely hold keys to a magical wallet alongside a Visa debit card and SEPA rails.
We’re a bridge between banks and self-custody wallets. Not a custodial wallet with buy and sell buttons.
Self-custody means true sovereignty with privacy. Permissionless transactions. Verifiable security on your terms. Complete transparency.
That’s what Bitcoin was designed for.
When you experience Bitcoin through heavily monitored, permission-required custodial services, you’re not experiencing Bitcoin. You’re experiencing a banking service that happens to reference Bitcoin prices in their database.
The future of Bitcoin isn’t about creating better banks with crypto branding. It’s about building tools that preserve Bitcoin’s revolutionary properties while making them accessible to everyone.
Your Bitcoin. Your keys. Your network. Always.
The choice between custodial and self-custody services isn’t about convenience versus control. It’s about whether Bitcoin remains Bitcoin or becomes just another banking product with crypto characteristics.
At Bringin, we chose to build for Bitcoin.
Thanks for reaching!
Prashashanth
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Bringin is Europe’s most complete Bitcoin app—combining self-custodial Lightning with euro banking services. Download on iOS and Android.