πŸ“– Developer Knowledge Base & Solutions

Practical, zero-install, step-by-step guides for modern software engineering, AI pipelines, API security, and local client-side workflows.

πŸ“‘ AI & Documents

How to Extract High-Fidelity Tables from PDF to Excel & Markdown for LLM RAG

Traditional text extractors scramble multi-column layouts and tabular data, causing retrieval failures in Vector databases (Pinecone, ChromaDB, LlamaIndex). Here is how to reconstruct clean table grids and contextual token chunks entirely on-device without cloud data leaks.

  1. Load your PDF: Open the PDF to Markdown & RAG Studio or PDF to Excel tool.
  2. OCR & Layout Analysis: On-device Web Workers scan bounding boxes and reconstruct rows and columns into valid GitHub-Flavored Markdown tables.
  3. Contextual Chunking: Select your desired token window (250–500 tokens) with semantic header metadata tags preserved across chunk boundaries.
  4. Export: Download clean .md, .xlsx, or copy JSONL vector embeddings.
πŸ”’ Security & APIs

How to Verify Stripe, GitHub & Razorpay Webhook Signatures Securely

Replay attacks and forged payloads occur when backend servers fail to cryptographically verify HMAC-SHA256 signatures. Verify incoming webhook headers locally before pushing code to staging.

// Standard HMAC-SHA256 Signature Verification Pattern const crypto = require('crypto'); const expected = crypto.createHmac('sha256', secretKey).update(rawPayload).digest('hex'); const isValid = crypto.timingSafeEqual(Buffer.from(signature), Buffer.from(expected));
  1. Paste the raw payload exactly as received in the HTTP request body.
  2. Enter your webhook signing secret (e.g. whsec_...).
  3. Provide the header signature (e.g., Stripe-Signature timestamp and hash).
  4. The tool computes the cryptographic digest with constant-time equality checks and reports verification status.
🐳 Cloud & DevOps

How to Generate Production Docker Compose Stacks for FastAPI, Postgres & Redis

Configuring network bridges, persistent volume mounts, health checks, and non-root user permissions in Docker Compose can be tedious. Use the visual generator to generate production-ready docker-compose.yml stacks.

  1. Select your backend runtime (FastAPI / Python 3.12, Node.js 22, Go, or Rust).
  2. Toggle database services (PostgreSQL 16 with automatic pg_isready health checks).
  3. Add caching (Redis 7.2 with AOF persistence enabled) and Reverse Proxy (Nginx / Caddy).
  4. Click Generate YAML and copy your verified, production-hardened compose file.
πŸ€– Agentic AI

Designing Visual Multi-Agent Workflows with Python LangGraph Export

Connect autonomous AI agents into directed acyclic graphs (DAGs) with state machines, supervisor nodes, conditional branch routers, and tool execution environments.

  1. Drag User Input, Reasoner (DeepSeek R1 / Claude), Code Executor, and Critic / Reviewer nodes onto the canvas.
  2. Wire outputs to inputs to construct feedback loops and self-healing cycles.
  3. Test the workflow in the interactive live simulator.
  4. Click Export Python (LangGraph) to download a clean, deployable StateGraph Python script.