Sergei C.

𝗕𝘂𝗶𝗹𝗱𝗶𝗻𝗴 𝗮 𝗦𝗮𝗮𝗦 𝗽𝗿𝗼𝗱𝘂𝗰𝘁 𝗮𝗻𝗱 𝘄𝗼𝗿𝗿𝗶𝗲𝗱 𝗶𝘁 𝘄𝗼𝗻'𝘁 𝘀𝘂𝗿𝘃𝗶𝘃𝗲 𝗿𝗲𝗮𝗹 𝘂𝘀𝗲𝗿𝘀?

Most founders reach me after a first version that demos well and breaks in production: data models that can't take a second tenant, billing that drifts out of sync, AI features that write nonsense into the database.

I'm Sergei. I build B2B SaaS and AI products end-to-end with a small senior team — so you get one person accountable for architecture and delivery, not an account manager.

▸𝗪𝗛𝗔𝗧 𝗜 𝗕𝗨𝗜𝗟𝗗

→ 𝗠𝘂𝗹𝘁𝗶-𝗧𝗲𝗻𝗮𝗻𝘁 𝗦𝗮𝗮𝗦 𝗣𝗹𝗮𝘁𝗳𝗼𝗿𝗺𝘀
Tenant isolation, data models, role-based access, and permissions that still hold when customer #50 arrives.

→ 𝗔𝗜 𝗔𝗴𝗲𝗻𝘁𝘀 & 𝗟𝗟𝗠 𝗙𝗲𝗮𝘁𝘂𝗿𝗲𝘀 𝗧𝗵𝗮𝘁 𝗦𝘁𝗮𝘆 𝗥𝗲𝗹𝗶𝗮𝗯𝗹𝗲
Agents with persistent state, guardrails, and predictable behaviour when the model is wrong — not a demo that works once.

→ 𝗕𝗶𝗹𝗹𝗶𝗻𝗴 & 𝗜𝗻𝘁𝗲𝗴𝗿𝗮𝘁𝗶𝗼𝗻𝘀
Stripe subscriptions and payment flows, OAuth, webhooks, third-party APIs, CRM/ERP integrations, data pipelines.

→ 𝗥𝗲𝘀𝗰𝘂𝗲 & 𝗣𝗿𝗼𝗱𝘂𝗰𝘁𝗶𝗼𝗻 𝗛𝗮𝗿𝗱𝗲𝗻𝗶𝗻𝗴
Products left by a previous team, built on a no-code platform, or generated by an AI tool — taken to production quality.

→ 𝗔𝗿𝗰𝗵𝗶𝘁𝗲𝗰𝘁𝘂𝗿𝗲 & 𝗧𝗲𝗰𝗵𝗻𝗶𝗰𝗮𝗹 𝗥𝗲𝘃𝗶𝗲𝘄𝘀
An independent read on what will break, what it costs to fix, and what to build first.

▸𝗖𝗢𝗥𝗘 𝗧𝗘𝗖𝗛 𝗦𝗧𝗔𝗖𝗞

◆ Backend: Python, FastAPI, Node.js, NestJS, Django, Laravel PHP
◆ Frontend: React, Next.js, TypeScript, Vue.js, Tailwind CSS
◆ AI & LLMs: OpenAI API, Claude, LangChain, AI Agents, RAG
◆ Databases: PostgreSQL, MySQL, Redis, Supabase, Prisma
◆ Billing & Integrations: Stripe, REST API, GraphQL, Webhooks, OAuth
◆ Cloud: AWS, GCP, Docker, CI/CD

▸𝗧𝗪𝗢 𝗪𝗔𝗬𝗦 𝗧𝗢 𝗦𝗧𝗔𝗥𝗧

◆ 𝟭. 𝗔𝗿𝗰𝗵𝗶𝘁𝗲𝗰𝘁𝘂𝗿𝗲 𝗼𝗿 𝗣𝗿𝗼𝗱𝘂𝗰𝘁𝗶𝗼𝗻-𝗥𝗲𝗮𝗱𝗶𝗻𝗲𝘀𝘀 𝗥𝗲𝘃𝗶𝗲𝘄
A capped, fixed-scope engagement. You get a prioritized list of what will break, what it costs to fix, and a plan you own — yours to take anywhere. Credited toward the build if we continue.

◆ 𝟮. 𝗦𝘁𝗿𝗮𝗶𝗴𝗵𝘁 𝗶𝗻𝘁𝗼 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁
Weekly sprints, if your spec is already solid.