Available for projects

I build DeFi products
that ship.

Henk ter Harmsel. Full-stack blockchain engineer & CTO.
15 years of shipping software. 5 years deep in Web3.

About

Not a consultant. A builder.

I'm Henk. I run Chaink, a one-man blockchain engineering outfit based in the Netherlands.

I don't do slide decks. I write smart contracts, build frontends, design system architecture, and ship products that handle real money. The kind of stuff where bugs cost millions and "move fast and break things" is a terrible idea.

Over the past 5 years, I've built NFT marketplaces processing $30M+ in volume, DeFi lending protocols with custom liquidation engines, and cross-chain infrastructure spanning EVM, Cosmos, XRPL, and Solana. Before Web3, I spent a decade building production software - backends, APIs, the full stack.

When I work with teams, I typically operate as a hands-on CTO or lead engineer. I'm the person who architects the system, writes the critical code, reviews every PR, and stays up at 3 AM when the liquidation bot is misbehaving.

Years shipping software15+

Years full-time Web35

Users across platforms40K+

Volume processed$30M+

Netherlands - Fully remote

Work

Things I've built

Production systems handling real users and real money. Not hackathon demos.

Bidds

NFT Marketplace & DEX

~40K users · ~$30M volume

Full-featured NFT marketplace and decentralized exchange on XRPL and Coreum. Minting, listings, auctions, royalty enforcement, and an on-chain name service. Built from scratch, end to end.

XRPLCoreumReactNestJSTypeScript

Lendore

DeFi Lending & Perps

Lending, borrowing, and perpetuals platform on Coreum. Custom liquidation engine, oracle integration, risk parameter management. The hard DeFi stuff.

CoreumCosmWasmRustTypeScriptPostgreSQL

Ledger Swap

Token Swap on XRPL

Token swap interface built as a Xaman xApp, powered by Bidds. Uses XRPL's native AMM and orderbook for on-ledger swaps with automatic slippage management. Frontend + backend + sync job.

XRPLReactNestJSTypeScriptXaman

DEX Aggregator

Multi-chain Routing

Cross-DEX routing engine spanning Uniswap, PancakeSwap, and other AMMs on EVM chains. On-chain price discovery with off-chain route optimization for best execution.

SolidityEVMNode.jsDeFi

XPUNKS

NFT Ecosystem & Gaming

NFT collection ecosystem with a built-in game (Eden). Community-driven project with staking, rewards, and a fully on-chain game loop.

XRPLReactGame DevNFT

Cross-chain Tokens

Multi-chain Infrastructure

Token implementations bridging EVM, CosmWasm/IBC, and XRPL. Standardized interfaces, bridge contracts, and cross-chain messaging.

SolidityCosmWasmIBCRust

OMNI Real Estate

Real Estate Tokenization

On-chain real estate tokenization platform through PSI Tech Solutions. Fractional ownership, compliance framework, and automated distributions.

BlockchainTokenizationSmart Contracts

Stack

Tools of the trade

I pick what works for the problem. Not what's trending on Twitter.

Smart Contracts

Rust

CosmWasm

IBC

Solidity

Anchor (Solana)

Chains

EVM

Coreum (Cosmos)

XRPL

Solana

Backend

TypeScript

NestJS

Node.js

PostgreSQL

Redis

Frontend

React

Next.js

Tailwind CSS

Infrastructure

AWS

Azure

Vercel

GitHub Actions

Docker

Services

How I can help

I work best embedded in your team. Whiteboard in the morning, code by afternoon, deploy by evening.

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Smart Contract Development

Solidity, Rust, CosmWasm. Auditable code that handles real money. From token standards to complex DeFi protocols.

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DeFi Protocol Design

Lending, DEXs, yield strategies, liquidation engines. I design the math and build the code. Tested against edge cases that keep you up at night.

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Technical Architecture

System design for blockchain products. Indexers, APIs, state management, cross-chain messaging. The invisible stuff that makes everything work.

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CTO-as-a-Service

Technical leadership without the full-time commitment. Architecture decisions, code reviews, team mentoring, and shipping discipline.

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Team Leadership

I have led engineering teams building production dApps. I write code alongside the team, not from a Notion board.

Contact

Let's build something

Got a DeFi protocol that needs building? A smart contract that needs auditing? A team that needs technical leadership? Drop me a line.

henk-ter-harmsel

I build DeFi productsthat ship.