X11

X11 Case Study: Digital Platform for Investor Management

Link

HTTPS://APP.CHATX11.COM/

Brief description

AI lawyer web service: an online legal consultant across jurisdictions powered by LLM, with its own knowledge base, subscriptions, and chat history.

Task

Build a product that gives users fast legal answers across jurisdictions through a specialized AI assistant, with authorization, pricing plans, and saved inquiry history.

About the project

We built a legal consultation service on top of AI model APIs. For the task we wrote a custom neuro-lawyer prompt and assembled a knowledge base for legal questions across jurisdictions. We delivered a full UI system with authorization, subscription plans, and stored user chat history.

Business benefits

•MARKET LAUNCH WITH A READY MVP IN 3 MONTHS BY INTEGRATING AI MODEL APIS INSTEAD OF TRAINING A PROPRIETARY MODEL FROM SCRATCH

•UP TO 80% BUDGET SAVINGS AT THE START — A CUSTOM PROMPT AND OWN KNOWLEDGE BASE DELIVER SPECIALIZED AI-LAWYER QUALITY WITHOUT THE COST OF TRAINING A MODEL

•MONETIZATION FROM DAY ONE — PRICING PLANS AND SUBSCRIPTIONS ARE BUILT INTO THE PRODUCT, PAID ACCESS TURNS ON WITHOUT EXTRA WORK

•SCALE WITHOUT REBUILDING THE PRODUCT — THE KNOWLEDGE-BASE ARCHITECTURE SUPPORTS NEW JURISDICTIONS AND A FUTURE MOVE TO A PROPRIETARY AI MODEL

Features

Registration and personal account

Fast user registration via email or phone

Authorization and access to the personal account

Store and delete user inquiry history

Access to saved dialogues

Manage basic profile data

Legal chat interface

Messenger-style interface for talking to the AI lawyer

Send text legal questions

Attach files to an inquiry

Save full dialogue history in the personal account

Separate new and past consultations

Continue a previous dialogue without losing context

Legal request processing

Understand the context of the user’s inquiry

Identify the legal problem from the message

Automatic clarifying questions

Collect missing information before forming an answer

Recognize legally significant entities: names, dates, organizations, amounts, statute articles, case circumstances

Form an answer using the user’s input

AI core and answer logic

Configure AI rules through prompt engineering

Create basic legal consultation scenarios

Configure answer limits and structure

Build clarifying-question logic

Support a dialogue consultation scenario

Architecture prepared for a later move to a proprietary AI model

Legislative knowledge search

Build an internal legal document base

Search legislative materials inside the platform

Use the internal base as the priority data source

Work with codes, laws, regulations, and other normative materials

Structure prepared to expand with case law and legal doctrine

Working with legal materials

Upload user files into the chat

Pass files into processing within the consultation scenario

Use attached materials as extra inquiry context

Store files within a specific dialogue

Subscription system

Paid plans can be connected

Access-limiting logic by subscription prepared

Further user segmentation by pricing plans supported

Limits on inquiry count, features, or processing volume

Payment integration

Ability to connect a payment provider

Support for YooKassa, CloudPayments, Stripe, or similar solutions

Payment logic for subscriptions or individual consultations prepared

Payment status handling inside the platform

Technology stack

1. Frontend:

React Native + Expo — single codebase for iOS, Android, and Web

React 19 + TypeScript — modern type-safe frontend

Expo Router — file-based routing and navigation

TanStack React Query — caching, sync, and data updates

NativeWind (Tailwind CSS) — utility-first styling

React Hook Form — auth, registration, and settings forms

Axios + Orval — typed API client and OpenAPI codegen

2. Backend:

ASP.NET Core 8.0 — server application foundation

ASP.NET Core Identity + JWT — authentication

Entity Framework Core 9.0.9 — ORM

Hangfire — background jobs

MailKit and MimeKit — email

3. API:

MediatR — CQRS for queries and commands

Swashbuckle — OpenAPI/Swagger docs

Asp.Versioning — API versioning

4. Integrations:

AWS SDK — Amazon S3

Stripe.net — payments

OpenAI — artificial intelligence

5. Databases:

PostgreSQL — primary database

6. Development tools:

Docker — containerization

Serilog — logging and monitoring

Working with the client

*Important: this is not project delivery work — it is work with the client specifically, and it is not in the estimate or commercial proposal; it is what we do to raise the product’s chance of successKnowledge that makes the client independent and resilientQuality code is the baseline. What really changes a project’s fate is the client’s ability to make the right decisions without us. We handed the client’s team not just a platform manual, but an understanding of its business logic: how the product economy works, where failure points are, how to read analytics and react in time. We ran training, modeled several crisis scenarios, and showed with live examples how to stay resilient when the market does not follow the plan. As a result the client cut launch costs, avoided typical beginner mistakes, and entered the market with a systemic view rather than a set of guesses.Our goal is not just development — it is our client’s success.

Design goals:

•REMOVE THE BARRIER “LEGAL HELP IS HARD AND EXPENSIVE”: A CONSULTATION SHOULD FEEL LIKE CHATTING IN A FAMILIAR MESSENGER

•TAKE THE USER FROM SIGN-IN TO THE FIRST QUESTION IN AS FEW STEPS AS POSSIBLE TO RAISE FIRST-DIALOGUE CONVERSION BY 20%

•SHOW PLAN VALUE TRANSPARENTLY SO THE MOVE TO A SUBSCRIPTION IS INTENTIONAL

Design results:

•FAMILIAR CHAT UI: THE USER ASKS THE FIRST QUESTION RIGHT AFTER SIGN-IN, WITH NO PRODUCT TRAINING

•THE AI LAWYER’S CLARIFYING QUESTIONS FEEL LIKE A NATURAL DIALOGUE — A LIVE CONSULTATION SENSATION GROWS, AND TRUST IN ANSWERS RISES

•INQUIRY HISTORY IS ALWAYS AT HAND: PAST CONSULTATIONS ARE EASY TO REOPEN, WHICH DRIVES REPEAT USE

•PLANS AND LIMITS ARE SHOWN CLEARLY: THE USER SEES WHAT THE SUBSCRIPTION GIVES BEFORE PAYING