Alexandr P.Private profile: Upwork shows its earnings only to signed-in members, so we check it every few weeks, not daily. MRR here is a rough estimate (Upwork's six-month earnings ÷ months active). Last read Nov 5, 2026.

⭐⭐⭐⭐⭐ "Alex and the entire team at Angle2 have been amazing to work with. They are an incredibly experienced team of designers and programmers and therefore are able to act as strategic partners. I look forward to our continued partnership." — 𝘉𝘦𝘯𝘫𝘢𝘮𝘪𝘯, 𝘍𝘰𝘶𝘯𝘥𝘦𝘳, 𝘈𝘣𝘭𝘦 𝘛𝘦𝘤𝘩𝘯𝘰𝘭𝘰𝘨𝘺 Most backend systems don't fail because of bad code. They fail because the architecture wasn't thought through before the first line was written - or because it was, and then the product outgrew it. I work with teams who need someone to think through the system first, build it right, or fix what's already broken before it becomes expensive. 𝐖𝐡𝐚𝐭 𝐈 𝐝𝐨 𝐰𝐞𝐥𝐥 • Step into existing codebases, understand what's actually happening, identify what's fragile, and propose a clear path forward - before touching anything • Design backend systems with explicit data contracts, clear service boundaries, and observable behaviour that stays predictable under real usage • Build and stabilise AI/LLM pipelines - retry logic, backoff strategies, structured prompt design, validation layers, embedding consistency - the parts that work in development and break in production • Design data processing systems with deterministic logic, traceable outputs, and confidence thresholds that make failures visible rather than silent • Write Scopes of Work that developers can actually execute against - concrete enough to review milestone by milestone Over 8 years, my team at Angle2 and I have built and hardened backends across scientific marketplaces, data aggregation platforms handling millions of records, internal operations tools, subscription platforms, and AI-integrated products — always with the same principle: architecture before code, reliability above development speed. 𝐖𝐡𝐚𝐭 𝐈 𝐛𝐮𝐢𝐥𝐝 𝑨𝑰 & 𝒅𝒂𝒕𝒂 𝒑𝒊𝒑𝒆𝒍𝒊𝒏𝒆𝒔 • LLM-integrated ETL pipelines with structured validation, retry logic, fallback handling, and traceable outputs • Embedding-based matching and entity resolution systems with confidence scoring and review queues • Batch processing systems designed for correctness and maintainability, not just throughput • Data ingestion and transformation pipelines across APIs, CSV, and external sources 𝑩𝒂𝒄𝒌𝒆𝒏𝒅 𝒔𝒚𝒔𝒕𝒆𝒎𝒔 & 𝑨𝑷𝑰𝒔 • FastAPI and Django backends with explicit validation, structured error handling, and clean data contracts • Async task systems: Celery, Redis, RabbitMQ, background workers, job orchestration • Role-based access, multi-tenant architecture, subscription and billing integration (Stripe) • PostgreSQL schema design, query optimisation, Manticore search for large-scale product catalogues 𝑨𝒓𝒄𝒉𝒊𝒕𝒆𝒄𝒕𝒖𝒓𝒆 & 𝒂𝒅𝒗𝒊𝒔𝒐𝒓𝒚 • Codebase audits with prioritised findings and concrete fix recommendations • Architecture design before development starts - module boundaries, integration points, risk identification • Milestone reviews with clear go/no-go judgments and structured feedback • Scope of Work production for freelance developer handoff 𝑪𝒍𝒐𝒖𝒅 & 𝒊𝒏𝒇𝒓𝒂𝒔𝒕𝒓𝒖𝒄𝒕𝒖𝒓𝒆 • AWS (EC2, RDS, S3, CloudFront, Lambda, SNS), GCP, Azure, Docker, CI/CD (GitHub Actions, GitLab CI) 𝐒𝐞𝐫𝐯𝐢𝐜𝐞𝐬 • Backend architecture audits and production stabilisation • AI/LLM pipeline design, implementation, and hardening • Data processing system design - ETL, matching, entity resolution, batch workflows • FastAPI / Django backend development • PostgreSQL optimisation and schema design • Technical advisory - Scope of Work, milestone review, go/no-go assessment • AWS infrastructure review and cost optimisation • CI/CD pipeline setup My background is senior Python backend engineering - ~20 years building systems where reliability isn't optional. FastAPI, Django, PostgreSQL, Redis, Celery, AWS - that's the everyday stack. The work I'm drawn to most is where the architectural decisions actually matter: AI pipelines that need to stay stable at scale, data systems where false positives have real cost, existing codebases that work at low volume and fall apart under load. If you need a backend built right from the start, a system stabilised before it becomes a problem, or an architect who can review what's already been built and tell you honestly what needs to change - I'd like to hear about it.