Capxul V2 Architecture

Technical Design Document - March 2026

Document Structure

This document defines the complete V2 architecture for Capxul, a financial operations platform on stablecoin rails. It is organized bottom-up by system layer, from on-chain infrastructure through money movement, data, identity, and operations.

Audience: Engineers and Claude Code (daily consumers building from this), investors, potential hires, and partners.

Status: Design Complete, Pending POC Validation

Part 1: Foundation

On-chain infrastructure (Safe, Payment Module, LlamaPay, Zodiac), smart account infrastructure (Openfort, session keys, auth, recovery).

Part 2: Money Movement

Payments and streaming, fiat ramps (HoneyCoin), cross-chain bridging (deBridge, Hyperbridge).

Part 3: Data and Intelligence

Financial document layer, event indexing, dashboard metrics, and scheduled reporting.

Part 4: Identity and Compliance

KYC/KYB via Shufti Pro, tiered verification, jurisdictional thresholds.

Core Principles

Three architectural invariants govern the entire V2 system:

Pull-based architecture. All funds flow through the employee’s smart account. Salary streams accrue to the smart account. Downstream routing (bank, external wallet, bridge) is configured by the recipient and executed from the smart account. Funds never skip the smart account.
Infrastructure sovereignty. Every critical component has a path to self-hosting or is on-chain and immutable. Key management (OpenSigner), recovery (Shield), smart account contracts, Safe modules — all are open source. The hosted API dependency is temporary and replaceable.
Facade pattern for external providers. Fiat ramp providers, bridge providers, and identity verification providers are abstracted behind interfaces. Adding or swapping a provider is a backend configuration change, not a platform rewrite. Convex is the source of truth, never the provider.