Looking to bring your next great idea to life? Or, maybe you already have an awesome piece of software built and want to give it a new twist.
✅ Top Rated Software Development
✅ Expert in Task Automation and API Integrations
✅ Microsoft Certified Professional with 10+ years of experience
✅ Trained on the latest SW developer trends, tools and tech
✅ Deliver high quality software based on SOLID architecture principles
✅ Get robust software that stands the test of time
TESTIMONIALS
There is no secret why I consistently receive positive feedback, including:
✌️ "Amazing service. Highly recommended!"
✌️ "Always very professional and communicative."
✌️ "Easy to work with, highly skilled and honest straight forward ideas."
✌️ "Once again excellent job and service for our project! Always professional and timely!"
✌️ "Very sharp. Awesome to work with. Clear and direct. Lot of know how! "
WHAT I OFFER
✅ Back-end Software Development
✅ API Integrations and Automation Development
✅ Web App Development
✅ Software Architecture Consulting
✅ MVP Product Development
ABOUT ME
Technically versatile software engineer with a passion for building data-driven
applications with 10+ years of development experience. Successful working as a
remote software engineer, collaborating in cross-functional teams and
demonstrating high-levels of social, cultural and emotional intelligence to
successfully deliver on business objectives
SKILL SET
► Programming Languages
C#, SQL, JavaScript, TypeScript, HTML, CSS/Sass
► Libraries & Frameworks
ASP.NET MVC, .NET Core, Entity Framework, LINQ, WPF, Angular, React, jQuery
► Tools & Platforms
MSSQL, MySQL, MongoDB, Elastic Search, Azure, PowerShell, NuGet, TeamCity,
Octopus Deploy, TFS, Git
🔥🔥🔥 ALL SET - LETS GO!
Done reading and want to get get started? Then click the "Hire" or "Invite"
LINQ
SQL
MongoDB
ASP.NET Core
C#
TypeScript
Elasticsearch
AngularJS
.NET Framework
Microsoft Azure
Azure Cosmos DB
Microservice
Azure Service Fabric
Microsoft SQL Server
.NET Core
Yasser V.
Queluz, Portugal
$125/hr
4.9
100 jobs
Startups, enterprises and public-sector organizations bring me in when the product needs strong technical decisions, not just execution - production AI systems, SaaS platforms and fintech, from architecture to live deployment.
Most engagements start with a fixed-price design phase that defines architecture, scope and roadmap, then convert into fixed milestones, so delivery stays structured and budget predictable. Rate $125-150/hr depending on complexity; most work is delivered as fixed-price milestones.
What I specialise in:
AI/LLM systems - RAG pipelines, multi-tenant AI assistants, agent orchestration, Claude/OpenAI integrations, structured outputs, eval pipelines.
SaaS platforms - multi-tenant architecture, subscription billing, RBAC, admin backends, scalable APIs across web and mobile.
Fintech/compliance - ACH, Stripe Connect, idempotent payment webhooks, audit logging, GDPR-compliant data.
Govtech/regulated - transparency platforms, donor-funded compliance, multi-language reporting.
Blockchain/Web3 - Solana smart contracts, SPL tokens, DeFi integrations.
Selected results (live demos and links in the Portfolio section):
Minerva (active production) - multi-tenant AI assistant platform architected end to end: organizations upload document libraries and deploy embeddable chatbots on their own knowledge base. Hybrid retrieval (BM25 + dense vector + semantic), Entra ID + RBAC + MFA, full tenant isolation, golden-query eval harness in CI. NestJS, Next.js, Azure OpenAI.
Diginak.ai (active production, lead architect) - logistics document automation that auto-processes ~78% of inbound PDF/CSV/Excel with zero human touch; the remainder routes to human review with confidence scores. Claude API + tool use, state-machine workflow engine, retry/idempotency, 850+ automated tests. NestJS, PostgreSQL.
Walletta AI Cashier (concluded May 2026, 5-star) - real-time voice agent with sub-500ms perceived latency. Claude + GPT-4o orchestration, structured tool calls with confidence-scored routing, persistent WebSocket, retry with circuit breaker. LiveKit, Deepgram, ElevenLabs, NestJS.
Damen Capital Portal (concluded May 2026, 5-star) - loan-servicing portal for a private lender with the full ACH lifecycle: tokenization, NACHA returns R01-R85, HMAC-verified idempotent webhooks, append-only audit log, OAuth 2.0 + RBAC, scheduled reconciliation. NestJS + Fastify, Supabase.
PulseYourBiz (active production) - all-in-one SaaS for service providers: bookings, payments, invoicing, CRM, analytics. Five-app Turborepo monorepo, Stripe Connect payouts, idempotent webhooks, React Native mobile. Docker + GitHub Actions.
ProveYourImpact (production) - multi-tenant governance/compliance platform for donor-funded projects in PALOP countries: 20 API modules, 9-role RBAC, configurable workflow engine, audit log, EU/UNDP/World Bank report generators in four languages. NestJS, Next.js, PostgreSQL + RLS.
Also shipped: no-code Solana token/DeFi platform with 1,500+ users (SwapForge), offline-first clinical decision support for underserved regions (ExtendYourClinic), multi-tenant VetSaaS with PostgreSQL RLS isolation (acti.vet), React Native apps live on both app stores (ForroAI).
Tech stack:
Backend: Node.js, NestJS, Python, FastAPI, REST, GraphQL. Frontend: React, Next.js, React Native, Expo, TypeScript, Tailwind. AI: Claude, OpenAI, RAG, pgvector, Azure Cognitive Search, structured outputs (Zod/Pydantic), prompt caching, tool use, eval harnesses in CI. Cloud: Azure (Functions, OpenAI, Entra ID, Key Vault, App Insights, Bicep IaC), AWS, GCP, Docker, GitHub Actions. Databases: PostgreSQL, MongoDB, Redis, Supabase, RLS tenant isolation. Blockchain: Solana, Anchor, SPL, Jupiter, Solidity, EVM.
Working model: 25-30 hrs/week across a small number of parallel engagements. Best fit when the product needs architectural ownership - not a fit for quick fixes or one-off tasks.
AI Agent Development
Generative AI
Retrieval Augmented Generation
Large Language Model
AI Consulting
Node.js
NestJS Development
Next.js
React
React Native
TypeScript
Python
PostgreSQL
Software Architecture & Design
Stripe
Angular
Blockchain Development
Blockchain Architecture
DevOps Engineering
Kristijan P.
Alges, Portugal
$35/hr
5.0
38 jobs
🚀 Top-Rated-Plus QA Tester | Software Engineer
✔️ 5+ years of experience in Quality Assurance, Software Testing, and IT solutions
✔️ Skilled in manual testing using real devices (iOS, Android, Windows, macOS)
✔️ Familiar with automated testing concepts and actively learning automation frameworks
✔️ Multilingual support for international projects 🌍
Additional Skills & Expertise
- Full-Stack .NET Developer – Experienced in backend & frontend development
- Adobe Photoshop Certified – Graphic design & digital editing
- PDF Editing & Document Management – Advanced document handling
- CRM Management – Proficient in maintaining and optimizing CRM platforms
Committed to delivering high-quality software and continuously improving. Let’s connect and collaborate! 🚀
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