Backend Lead Developer

1 week ago

Belgrade, Central Serbia DcentraLab Full time

Location: Remote/Belgrade

Type: Full-time

Web3 Index is a business development tool designed to discover, analyze, and curate the most comprehensive information about blockchain and crypto projects.

We aggregate and enrich data from sources like CoinGecko, CoinMarketCap, CypherHunter, and more. Using AI (ChatGPT, Perplexity, CrewAI), advanced scraping techniques, and databases (PostgreSQL, MongoDB), we deliver high-quality, actionable insights to users.

Our platform powers:

  • Data aggregation & enrichment (socials, team, LinkedIn, project metadata).
  • AI-powered search & embeddings using MongoDB Vector DB.
  • AI agents that research and validate project data.
  • Integrations with TalkJS, Apollo, Slack, Twitter, Cloudflare, Postmark, Tranzilla, SimilarWeb, and more.

We are now looking for a Backend Lead Developer to lead our technical backend efforts, drive innovation, and ensure scalability of our growing platform.

Responsibilities

  • Lead backend development: Drive feature design, architecture decisions, and technical roadmap for the platform.
  • Research & Development (R&D): Experiment with new technologies, AI models, and scraping methods to continuously improve data quality and system performance.
  • Web scraping & data pipelines: Design and maintain robust scraping systems using Python libraries (e.g., Scrapy, Requests, BeautifulSoup, Playwright).
  • Database management: Optimize and maintain PostgreSQL (with Alembic/Alchemy) and MongoDB (vector search/embeddings).
  • AI & agent integration: Work with LLMs (ChatGPT, Perplexity) and CrewAI to build and scale AI-driven features.
  • DevOps & infrastructure: Manage AWS services (S3, EC2, Lambda, CloudWatch, API Gateway, SageMaker) and automation (Bash scripting, cron jobs).
  • Blockchain expertise: Analyze and interact with smart contracts (Solidity – entry level), understand blockchain data structures, and integrate relevant protocols.
  • Team leadership: Mentor developers, perform code reviews, enforce best practices, and ensure high-quality deliverables.
  • Integration management: Oversee and expand integrations with 3rd-party APIs and services (TalkJS, Slack, Twitter, Apollo, etc.).
Requirements
  • 5+ years of backend development experience, with at least 2 years in a lead/architect role.
  • Strong Python skills (FastAPI, Flask, Django or similar).
  • Proven experience with web scraping at scale.
  • Solid understanding of PostgreSQL (schemas, migrations, performance tuning) and MongoDB (vector DB, embeddings).
  • Familiarity with AI/LLM frameworks and data pipelines.
  • Hands-on AWS experience (EC2, S3, CloudWatch, API Gateway, Lambda, SageMaker).
  • Knowledge of blockchain/web3 ecosystems, with the ability to read/write Solidity contracts (entry-level).
  • Strong DevOps skills (Bash, cron, deployment automation).
  • Excellent problem-solving skills and ability to take ownership of complex systems.
  • Strong communication and leadership abilities.

Nice-to-Have

  • Experience with CrewAI or other agent frameworks.
  • Knowledge of data enrichment and NLP pipelines.
  • Exposure to business intelligence tools and analytics.
  • Open-source contributions or published work in scraping/AI/blockchain.

What We Offer

  • Opportunity to lead a cutting-edge Web3/AI product.
  • Work with modern stacks (AI, blockchain, web scraping, embeddings).
  • Flexible remote-first work environment.
  • Growth potential in leadership and architecture.
  • Competitive compensation package.

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