Sikoba set out to bring legal certainty and auditability to informal peer-to-peer (P2P) lending, an economy serving hundreds of millions of unbanked micro-entrepreneurs worldwide. Elementica joined the project to engineer a full-featured React web platform matching their existing mobile app, while implementing the client-side cryptographic layer — public-key generation, device binding, and payload hashing — required to secure multi-million-dollar credit networks across emerging markets.
Product Modernization/Blockchain/Fintech
Global footprint across Luxembourg, Colombia, Kenya, and Pakistan
Named among top emerging Bitcoin/Blockchain projects on Crunchbase
100% feature parity between web and mobile experiences
Custom hardware-bound device pairing with Secp256k1 key generation
Client context
In many developing economies, traditional banking infrastructure is out of reach for small merchants. Over 300 million micro-businesses rely entirely on informal IOUs — unwritten or handwritten promises to pay back suppliers or peers. These agreements carry no legal enforcement, generate no credit history, and frequently fall apart due to record disputes.
Sikoba created a decentralized credit platform designed to turn paper promises into cryptographically signed, legally binding digital obligations. By tracking peer-to-peer credit lines, calculating creditworthiness, and automatically clearing circular debts (where A owes B, B owes C, and C owes A), Sikoba dramatically reduces the physical cash required to settle market transactions.
The challenge
Elementica stepped into a system with an active React Native mobile application, tasked with building a feature-complete web platform while reinforcing the core security layer. The project involved two critical challenges:
- Key Management Without UX Friction: Most non-technical users in target regions cannot manage complex seed phrases. We had to implement public-key generation, payload encryption, and hardware-device binding directly in the client layer without creating user drop-off.
- Bi-directional Feature Synchronization: The web portal had to mirror complex mobile interactions — such as IOU creation, dynamic interest calculations, multi-currency credit limits, and dispute resolutions — without duplicating business logic or introducing race conditions into the ledger backend.
Elementica's role
We led the web platform build and co-engineered the cryptographic backend alongside the client's blockchain team. Our focus spanned frontend React architecture, client-side encryption modules, state sync pipelines, and data-visualization tools for financial activity.
The solution
Web Platform Build & Logic Alignment
We built the web application on React, refactoring core state-management routines so business logic could be shared between the mobile (React Native) and web codebases. Users can initiate an IOU on their phone, manage credit limits on the web, and accept repayment requests interchangeably with real-time state updates across devices.
End-to-End Cryptographic Security Layer
To ensure tamper-proof transactions, we implemented client-side cryptographic operations using the Secp256k1 elliptic curve — the same curve used by Bitcoin. Private keys are derived locally on the user's device using Argon2 key stretching and combined with SHA-256 hashing to sign transaction payloads. We engineered a custom device-binding protocol that verifies hardware identity tokens before permitting key usage, isolating accounts from unauthorized web sessions.
Dynamic Financial Analytics & Circular Clearing Dashboards
To give power users and micro-entrepreneurs clarity over their exposure, we built a modular widget engine. Users can filter transaction histories, run real-time audits on active credit lines, and track automatically cleared circular debts — visualizing how system-wide netting reduces their total cash obligation.
Engineering decisions that mattered
Statically Typed Backend with Crystal & Lucky
To handle high-throughput cryptographic verification without high infrastructure costs, the backend was built using Crystal on the Lucky framework. Crystal provides C-like performance and low memory consumption while retaining Ruby-like developer speed. This allowed the API server to parse and verify cryptographic signatures with sub-millisecond overhead.
Decentralized Consensus via Babble Engine
Instead of relying on high-cost public EVM chains with unpredictable gas fees, the system utilizes Babble — an Asynchronous Byzantine Fault Tolerant (aBFT) consensus engine. Babble processes transactions off-chain at high speed while maintaining distributed, immutable consensus across participating validator nodes.
Results
Sikoba now operates a unified web and mobile fintech platform capable of converting informal promises into audited financial records. The system provides verifiable credit histories for unbanked micro-businesses, while its circular-debt clearing algorithm automatically nets out chained obligations — allowing local trade ecosystems to flourish even when local currency liquidity is scarce.
Product evolution
The platform is expanding beyond P2P credit into municipal local-currency implementations and direct micro-grant distribution. Following early operations in Colombia, Kenya, and Pakistan, Sikoba signed its first formal local-currency contract in Luxembourg, laying the groundwork for sovereign and municipal credit-token programs.
