About the Role: "Senior Backend Engineer – Python & FastAPI (Document AI Systems)Duration : 6 monthsExp - 9+yearsLocation: RemoteBudget - 700rs/hr+GST ( I'll increase the budget based on exp )Timings: Full Time (40 hrs per week) - 5.30pm to 2.30amNotice Period: (Immediate Joiner - Only)Role OverviewWe are looking for a Senior Backend Engineer with strong Python and FastAPI experience to build and scale a document-processing backend that handles large, complex PDFs and AI-driven classification workflows.This role focuses on reliability, performance, and system design — building backend services that can process 200+ page documents, integrate with LLMs, and support robust exception handling, auditability, and cost-efficient execution.A key part of this role is designing and working with document taxonomies that drive classification, multi-page document assembly, confidence scoring, and downstream compliance workflows.Required Skills & Experience8-10 years of strong hands-on experience with Python and FastAPIProven experience with PDF processing using libraries such as PyPDF2, pdf2image, or similarExperience integrating LLM APIs for document analysis or classification (GPT-4 Vision API preferred)Hands-on experience with Google Cloud Platform, including Cloud Storage, Firestore, Cloud TasksStrong understanding of asynchronous job patterns, including background workers, queues, and retry logicSolid systems thinking, with a focus on Error handling, Data lineage, Audit trailsExperience designing or working with document taxonomies, classification schemas, or structured labeling systems for AI-driven workflowsExperience with OCR or document processing systemsBackground in financial services or compliance-oriented projectsExperience with taxonomy versioning, confidence thresholds, or rules-based validationSupport loan processing workflows by classifying, assembling, and validating borrower documents (e.g., KYC, income proofs, bank statements, agreements) using taxonomy-driven rules, confidence scoring, and exception handling to enable faster and auditable credit decisionsKey ResponsibilitiesDesign and build backend services to reliably process large PDFs (200+ pages)Implement AI-based document classification using a defined taxonomy, including confidence scoringDesign and maintain document taxonomies that drive classification, grouping, and validation logicSupport multi-page document assembly based on taxonomy-driven rules and page-level signalsBuild robust exception detection and recovery mechanisms, including “needs review” and fallback pathsImplement audit trails and data lineage, including taxonomy versioning and classification rationaleOptimize system performance and architecture to control infrastructure and AI inference costsWhat We’re Looking ForA backend engineer who thinks in terms of systems, not just endpointsStrong ownership of failure modes, edge cases,
