FINTECH SOFTWARE ENGINEERING

Build What Moves Money.

ClearClients builds secure payment APIs, fintech applications, backend systems and cloud delivery workflows around real transaction flows.

✓ Live applications✓ Public source code✓ API documentation✓ Automated delivery
ClearClients fintech engineering dashboard with payment API and M-Pesa flow
SOFTWARE ENGINEERING SERVICES

Specific Engineering for Specific Product Problems

Each service starts with the operational problem, then connects architecture, implementation and deployment to measurable proof in working software.

Payment APIs & Gateways

Build payment services and integrations for M-Pesa, mobile money, financial platforms and digital applications.

ProblemPayment products often become fragile when transaction initiation, callbacks, retries and reconciliation are handled as separate pieces.
M-PesaDarajaSTK PushWebhooks

Fintech Applications

Develop financial platforms, transaction systems, payroll applications, reporting tools and operational software.

ProblemDisconnected workflows and manual financial processes create operational friction and make product changes expensive.
PaymentsTransactionsPayrollReporting

Backend & API Development

Design and build secure REST APIs, backend services, microservices and enterprise integrations.

ProblemFrontend products cannot remain reliable when core business rules, integrations and data access are tightly coupled or poorly tested.
PythonFastAPIJavaSpring Boot

Cloud Engineering

Design and deploy applications and infrastructure on modern cloud platforms with security and reliability in mind.

ProblemApplications become difficult to operate when deployment, infrastructure and monitoring depend on undocumented manual steps.
Microsoft AzureAWSContainersNetworking

DevOps & CI/CD

Automate software delivery through repeatable build, test, deployment and infrastructure workflows.

ProblemManual release steps slow delivery and allow defects or configuration drift to reach production.
GitHub ActionsGitLab CIJenkinsDocker

AI Engineering

Integrate modern AI capabilities into software products, engineering workflows and operational systems.

ProblemAI features fail when they sit outside the product workflow, lack review controls or cannot connect safely to business data and tools.
OpenAIChatGPTCodexClaude
M-Pesa Payment Gateway payment engineering visual
FEATURED ENGINEERING PROJECT

M-Pesa Payment Gateway

Production-structured M-Pesa payment service covering STK Push initiation, asynchronous callbacks, transaction states, retries, refunds, analytics and transaction event tracking.

PROBLEM

Businesses need a reliable way to initiate M-Pesa payments and reconcile asynchronous transaction confirmations without fragile manual checks.

SOLUTION

A FastAPI payment service manages STK Push requests, callbacks, transaction states, retries, refunds and operational tracking as one workflow.

✓ Live application✓ Swagger API documentation✓ Callback and webhook flow✓ Docker and GitHub Actions delivery
PROJECT PROOF

Working Applications Across Payments, Banking and Payroll

The strongest proof is a system you can open, inspect and trace from user flow through API and deployment.

M-Pesa Payment Gateway project preview
FINTECH / PAYMENTS

M-Pesa Payment Gateway

Production-structured M-Pesa payment service covering STK Push initiation, asynchronous callbacks, transaction states, retries, refunds, analytics and transaction event tracking.

✓ Live application✓ Swagger API documentation✓ Callback and webhook flow
Bank Transaction API project preview
FINTECH / BANKING

Bank Transaction API

Full-stack banking application demonstrating REST API engineering, JWT authentication, account operations, transfers, transaction history, automated testing and cloud deployment.

✓ Live authenticated dashboard✓ Interactive Swagger API✓ Automated API tests
KenPay, Kenyan Payroll System project preview
FINTECH / PAYROLL

KenPay, Kenyan Payroll System

Full-stack Kenyan payroll application calculating PAYE, NSSF, SHIF, Affordable Housing Levy, net salary and employer cost through a web application and REST API.

✓ Live web application✓ REST API✓ Statutory calculation engine
PAYMENT ENGINEERING

Software Built Around the Full Transaction Flow

Payment reliability depends on validation, states, callbacks, retries, reconciliation and operational visibility working together.

CUSTOMER
→
APPLICATION
→
PAYMENT API
→
M-PESA
→
CALLBACK
→
TRANSACTION STATE
→
RECONCILIATION
SOFTWARE DELIVERY

How We Build

The SDLC keeps requirements, architecture, code, tests and production operation connected.

01

Plan

Requirements, scope, risks and success criteria.

02

Design

Architecture, API contracts, data models and UI/UX.

03

Build

Frontend, backend, integrations and infrastructure.

04

Test

Unit, API, integration and security validation.

05

Deploy

CI/CD, containers, cloud and health checks.

06

Operate

Monitoring, logs, incidents, updates and performance.

ENGINEERING STACK

Technologies We Build With

Application development, cloud infrastructure, software delivery and artificial intelligence sit in one engineering stack.

Programming

PythonJavaJavaScriptTypeScriptSQL

Backend

FastAPISpring BootNode.jsPydanticREST APIsSOAP APIs

Cloud

Microsoft AzureAWSCloudflareRender

DevOps

GitGitHubGitHub ActionsGitLab CIJenkinsDockerKubernetesTerraform

AI

OpenAIChatGPTCodexAnthropic ClaudeGoogle GeminiAI AgentsMLOpsLLMOps

Data

PostgreSQLSQLSQLiteVector Databases
ENGINEERING LEADERSHIP

Samuel Mutua Kimani

Co-Founder & Chief Software Engineer

Software, Cloud and AI Engineering Leadership

Experience spans system administration, cloud engineering, software development, DevOps and AI/ML operations, with current work centered on backend APIs, fintech software, deployment automation and AI integration.

Master of Science in Artificial Intelligence
The Open University of Kenya, Sep 2026 - Dec 2027

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