PunarvPawade

Experience

1. Dec 2024 — Present

   AFT Group

   Software Engineer

   Automotive retail and finance software for UK dealers: a multi-tenant website platform with an AI page builder, cloud telephony, a dealer management system and a used-car marketplace.

   Key projects

   AI agents on live websitesLet Claude or ChatGPT manage a customer's website without being able to break it.Compare-and-set, Idempotency keys, Preview-then-confirm writes, Spend caps and concurrency limits, Least-privilege scoped keys

   Agents could act outside their tenant, overwrite human edits, publish by accident, run up the platform's AI bill, or apply a retried call twice.

   • MCP server with about 60 tools, OAuth with a consent screen, and scoped, expiring, tenant-bound keys
   • Draft-only writes with confirm tokens tied to the exact previewed state, plus idempotency keys on every write
   • Compare-and-set on a SHA-256 config version, Redis concurrency slots and per-tenant daily spend caps
   • Agent-written pages became the default, with a validator and an authoring guide: $0 platform AI spend, verified in production

   The hard part: Timestamps couldn't serve as the version because browser saves never bumped them. The version is a hash of the stored config instead.

   • FastAPI
   • Next.js
   • MongoDB
   • Redis
   • OAuth 2
   • MCP

   Cloud phone system for dealershipsBrowser and mobile softphone, call queues, recordings and usage billing, embedded in a CRM.Idempotent claims, Outbox pattern, Reconciliation, Lease-based jobs, Fan-out routing

   Calls had to reach every free salesperson at once, ring exactly once on a phone that was killed, and every billable second had to be accounted for.

   • Ring-everyone routing on Twilio TaskRouter, made idempotent with a Postgres partial-unique-index claim
   • Outbox billing pipeline with nightly reconciliation, closing call paths that had gone unbilled
   • Recording offload to Cloudflare R2 with SHA-256 read-back verification and manager-only column-level access
   • Native calling in React Native (FCM, PushKit, CallKit), taken through iOS App Review

   The hard part: One unanswered call re-entered the assignment callback four times in 30 seconds. Making the claim idempotent at the database layer fixed the whole class of bug.

   • TanStack Start
   • Cloudflare Workers
   • Supabase
   • Twilio
   • React Native

   LLM page builder that doesn't regressA chat-to-React page builder that is still stable on the tenth edit.AST-based patching, Intent routing, Provider pinning, Cost and latency observability

   Follow-up edits quietly changed sections the user never touched, and some model failures were intermittent and silent.

   • Babel AST section extraction and splicing, with a validated intent router and undo
   • Database-managed model catalog with provider pinning and served-by logging
   • Diagnosed failures by pinning each of a model's six upstream hosts in turn, and found three distinct failure modes
   • Billed-cost tracking and per-model timeouts based on measured latency

   The hard part: The model was copying the full-page code from its own earlier turns, which outweighed the system prompt. Normalising the chat history fixed it.

   • Next.js
   • Vercel AI SDK
   • OpenRouter
   • Babel
   • Zod

   Keeping 100+ dealer sites healthyIncident-driven reliability and security work on a multi-tenant platform.Tenant isolation, Allow-listed data exposure, Retention policies, Keyset pagination, Covering indexes

   One platform hosts every dealer's site, so one tenant's bug, leak or slow query becomes everyone's problem.

   • Tenant-isolation hardening: tenant derived from the session, allow-listed public data, constant-time secret checks, CI guard tests
   • Found why backups grew unbounded and pruned the store from 120 GiB to 47 GiB
   • Traced a frozen analytics dashboard to a hidden 1,000-row cap; in-database aggregation took it from ~160 to the real ~23,900 visitors
   • Rebuilt a silently stalling logging pipeline, and fixed intermittent TLS certificate failures

   The hard part: The backups grew because snapshots were grouped by an ephemeral container ID, so retention never matched anything.

   • Docker
   • Traefik
   • Grafana / Loki
   • Postgres
   • GitHub Actions

   Also

   • Built CRM single sign-on with algorithm pinning, issuer allow-listing and replay protection
   • Re-architected the nightly multi-dealer stock sync into a BullMQ fan-out with per-dealer retries
   • Built WhatsApp magic-link login that signs in the original tab in real time over Socket.IO and Redis
   • Built and ran a FastAPI vehicle recommender, and migrated it from Pinecone to self-hosted Qdrant

2. Jun 2024 — Dec 2024

   MetabotAI

   Software Engineer

   Crypto trading tools for Solana and EVM chains.

   • Built a high-speed Telegram trading bot with real-time market data
   • Built an indexer that picks up new Solana and EVM tokens as they launch
   • Integrated 1inch, Uniswap and Jupiter for cross-chain swaps

3. Apr 2023 — May 2024

   Lazarus Network

   Full Stack Developer

   Joined as an intern and was promoted to full-time. Backend in Go and Node, frontend in Next.js, cloud infrastructure.

   • Erebrus: gRPC auth middleware and a central gateway for VPN nodes, with peer discovery over libp2p
   • Sotreus: wallet-authenticated VPN and firewall deployment with Stripe subscriptions
   • MyriadFlow: complete backend for an NFT launchpad and marketplace