Build a Secure, Self-Hosted Telegram AI Assistant (Core Platform) – Python, PostgreSQL, Docker

I need a backend Python developer to build a Telegram AI assistant on my Ubuntu VPS. The system must be Dockerised, fault-tolerant, hardened, backed up hourly to a separate server, and designed for future telephony integration (3CX with a GSM gateway for inbound/outbound calls). You do not need GSM hardware expertise – only to build a secure API tool and a reserved webhook port for later use. Scope: 1. Telegram Bot: Multi-user (5‑10), natural language, long-term memory per user (PostgreSQL). 2. Data Handling: Manual input via paste, .xlsx/.csv upload, or formatted text. Parse, validate, deduplicate, store in approved schema. Export to Excel/CSV on demand. 3. Pluggable API Tool: Generic REST client for future services (3CX, SMS, etc.). Encrypted secrets, never logged. 4. Scheduler: Recurring tasks set via Telegram. Missed runs logged, re-triggerable from dashboard. 5. Dashboard: Light Python web app (Flask/FastAPI/Streamlit) – conversations, tasks, system health, logs, data management. Password-protected, configurable port. 6. Backup and Recovery: Hourly backup of DB, configs, files to separate server (SSH/rsync). Retention: 24h local, 7 daily remote. One-command restore. Stress test on fresh server (live in under 1 hour). 7. Security: UFW firewall (only SSH, HTTPS, dashboard, reserved 3CX port), fail2ban, non-root user, rate limiting, sanitised logs, resilient webhook port. 8. Architecture: Fault-tolerant, isolated modules, retries, process isolation. Modular design so I can add specialised agents later without rewriting. Exclusions: No web scraping, autonomous browsing, payments, ticket booking, form filling, actual 3CX logic, SMS integration, or AI self-coding. Only the extensible platform. Skills: Python, PostgreSQL, Docker, REST APIs, Linux admin, Telegram Bot API, Flask/FastAPI. Budget and Timeline: Fixed $6,500. Prototype in 5‑6 weeks, final delivery in 8 weeks. Milestone payments in escrow, released after I test each stage: · 10% Setup and server hardening ($650) · 25% Core bot, memory, data input/export ($1,625) · 25% API tool, scheduler, basic dashboard ($1,625) · 25% Backup, security, complete dashboard ($1,625) · 15% Documentation, handover, 30-day support ($975) Working Process: Weekly progress review (call or text) to inspect completed work and align on next steps. Direct communication expected. To apply, confirm: · You have built a similar Telegram bot with memory (share examples). · You are proficient with PostgreSQL, Docker, and server hardening. · You can work within the fixed budget and start within 1‑2 weeks.