Programming>Back-end Development

Backend API development

Backend API development
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About this service

I design and build reliable backend systems in Python and Django, from REST and GraphQL APIs to async pipelines and event-driven architecture. I work to production standards: tested, observable, and built to scale without rewrites. Good fit if you need a backend that holds up under real load and is easy for your team to maintain.


Servie packages

You can explore ready-made packages created by the expert below. The final price and the content of the work will be agreed upon after getting in touch.

API Starter - MVP Stage from
€900.00

Up to 5 REST endpoints with basic CRUD, input validation, and error handling. Suitable for MVPs or adding a small feature to an existing backend.

Full API Build from
€3,000.00
Production Backend from
€5,000.00

Service requirements

The client must have a defined project scope or a brief describing the system's purpose, expected traffic, and any existing infrastructure. Access to the codebase repository and relevant environment configs (staging/production) is required before work begins.

Talent information
Farjmand Z
Farjmand Z
Full Stack Engineer
Tampere
English
40-59 / h
Contracts
Freedomly Code of Conduct
Read here
About Me

Shipping slows down when the backend gets messy. I spend most of my time making sure that doesn't happen, through clean architecture, solid integrations, and observability tooling that keeps teams unblocked.

Most recently at Podero I owned a dozen third-party integrations (Bosch, Daikin, SMA, Smartcar) and built the Claude agents now used by 15 people across product, engineering, and customer success, diverting around 8 PRs a month away from the engineering queue.


I work across the full stack in Python, Node.js and TypeScript, and I care a lot about clean...

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Skills & Tools
front_end_development
system_architecture
web_development
back_end_development
api_development
+24
Interests
Barbecue
Basketball
Cooking and Baking
Dance
Knitting and Crocheting
+2

Work experience

Podero
1/2024 - 3/2026
Senior Full Stack Engineer
<p>--- Device Integration at Scale</p><p>Designed and shipped production integrations for 7+ OEMs including Vaillant, Bosch, Daikin, Nibe, Viessmann, SMA, and Smartcar — covering OAuth2, API client development, real-time telemetry ingestion, and remote device control, all behind feature flags for safe rollouts.</p><p><br></p><p>--- Energy Optimization &amp; Automation</p><p>Built asynchronous pipelines for energy trading and device steering decisions, delivering ~27% electricity bill savings for customers. Developed pricing engines resolving spot market and day-ahead prices, plus daily statistics pipelines from raw measurements to customer-facing dashboards.</p><p><br></p><p>--- EV Charging</p><p>Built the EV platform layer: webhook-based onboarding via Smartcar, brand-aware device selection, idempotent data processing, and a resilient charging command system with retry scheduling.</p><p><br></p><p>--- Frontend &amp; Localization</p><p>Led a full rebrand of the device onboarding experience (React/TypeScript), simplified flows, improved error handling, and shipped the platform in 4 European languages.</p><p><br></p><p>--- Platform Infrastructure &amp; DX</p><p>Built shared libraries adopted across all integrations: HTTP tracking client, API response storage, retry-aware cache locking, and a data validation framework. Reduced integration duplication and accelerated onboarding of new manufacturers.</p>
Reality Metaverse
9/2022 - 5/2025
Backend and Blockchain Engineer
<p>Web3 startup building fractional NFT (fNFT) infrastructure on the Polygon blockchain - enabling users to own, trade, and earn royalties from fractional digital assets.</p><p><br></p><p>- Engineered backend services for fNFT auctions, trading, and passive income distribution, bridging on-chain smart contract events with off-chain processing systems.</p><p><br></p><p>- Built and stabilized asynchronous pipelines for wallet events, asset transfers, and royalty distributions on Polygon; added observability instrumentation throughout.</p><p><br></p><p>- Set up BigQuery analytics on GCP to monitor passive income generation, fNFT transaction volumes, and user onboarding activity at scale.</p><p><br></p><p>- Migrated approximately 40% of legacy Web2 user flows to Web3 architecture, integrating wallet authentication and smart contract state into the React frontend.</p><p><br></p><p>- Built a React marketplace for fNFT browsing, buying, and selling.</p>
Biztrons
1/2021 - 9/2022
Frontend and Blockchain Engineer
<p>- Dutch Auction Smart Contract: Developed a dutch Auction smart contract for Ethereum blockchain in solidity having features of whitelisting and OG minting. Used Remix IDE for compiling and testing.</p><p><br></p><p>- Solana NFT Minting Contract: Developed a program in Rust to mint NFTs in Solana Blockchain using Metaplex Storefront.</p><p><br></p><p>- NEAR Protocol Contract: Developed a Rust program that enables users to fractionalize NFTs while minting.</p><p><br></p><p>- Cardano Tokenization: Developed and minted Native Tokens in Cardano Blockchain using cardano-cli and Daedalus Wallet.</p>

Education

Punjab University
Associate Degree of Information Technology, Computer Science
Graduation 2018

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