UserFI

UserFI

UX that makes finance clearer — plus AI tools your team can run.

We design and ship product experiences for FinTech, Web3, and complex B2B. We also turn that expertise into MCP tools and kits so your agents use the same standards.

Book a sessionWhat we do

DeFi UX MCP

score_screenshot

cognitive-bias-resistance

Anchoring

3/10

Fail

Web3 Onboarding

Continue with

GoogleApple

or

Connect wallet

Trading UI Kit

Long

BTC-PERP

Leverage3.5×

Liq. $61,240 · 28% to liq.

Transaction reverted

INSUFFICIENT_OUTPUT_AMOUNT

Slippage 0.5% was too tight for this pool.

Retry

Risk disclosure

High-leverage position

Liquidation can close this position without a further prompt.

Cooling-off: 24h remaining

Wrong network

Switch to Arbitrum

alice.eth · 0xA31c…9F2e

ETH-PERP+2.41%

Writing

From the blog.

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11 Aug 2026

AI builds and tests the code. Here’s how it can test UX.

Why product teams need UX guides and feedback loops — not just linters, type checks, and test suites Continue reading on RAY GROUP »

19 Jul 2024

Converting Web UI for Mobile Apps

Creating a consistent and high-quality user experience across both web and mobile platforms is essential in today’s digital age. Continue reading on Frontend Weekly »

8 Jul 2024

Enhancing Accessibility and Usability in Mobile Applications: A Comprehensive Guide

In today’s digital era, mobile applications are an integral part of our daily lives. However, the true potential of these apps can only be… Continue reading on Bootcamp »

12 Apr 2024

Why a User Experience Audit is Invaluable for Your Business

In today’s fast-paced digital world, businesses continually strive to stand out and captivate their audience. Continue reading on Bootcamp »

8 Jun 2023

Example of UX laws applied in Decentralized Exchanges

There are several UX laws that can be applied in decentralized exchanges to improve the user experience. Here are a few examples: Continue reading on Bootcamp »

Speaking

Conference talks.

Ethereum Community Conference · EthCC 6

Cognitive biases and heuristics applied in DeFi

See all talks →

About

Understand people. Ship with better tools.

UserFI is the product practice of L-LINE DIGITAL. Human-centred UX, engineering, and agent tooling for FinTech, Web3, and complex B2B.

10+
Years of combined experience
4
International conference talks
100%
Client-led approach

Services

UX reviews, agent setup, and delivery — pick what you need.

Research, design, engineering, and MCP tooling under one roof. Hire us for the full arc or a single piece.

Design & Prioritisation

User research, interaction design, and roadmap prioritisation — what to build next, and why.

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UI / UX Online appointment

A 30-minute review of your product with clear next steps. Book online.

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Engineering & Deployment

Software engineering and deployment — shipping working product end to end, not just designs.

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AI & Agentic Development

MCP servers, agent stack setup, and human-signed UX reviews in your repos.

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DeFi UX MCP Pro

An MCP server with the UserFI DeFi UX rubric, named patterns, and cognitive-bias glossary. Free tier installs in two minutes; Pro adds the extended corpus and commercial licence.

See pricing

Contact

Tell us about your project.

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