Senior Backend Engineer - Python & FastAPI

Senior Backend Engineer - Python & FastAPI (Document AI Systems)Location : RemoteEmployment Type : Full-Time (40 Hours/Week)Notice Period : Immediate Joiners OnlyExperience Required : 8+ YearsAbout the Role : We are looking for a highly skilled Senior Backend Engineer with deep expertise in Python, FastAPI, Document AI, OCR, and Large Language Models (LLMs) to design, build, and scale enterprise-grade document processing platforms.The ideal candidate will have extensive experience developing backend systems that process large PDF documents (200+ pages), perform AI-driven document classification, support taxonomy-based workflows, and ensure high reliability, auditability, and compliance.This role is perfect for engineers who think beyond APIs and focus on scalable architecture, workflow automation, error handling, and intelligent document-processing solutions.Key Responsibilities : - Design and develop scalable backend services using Python and FastAPI- Build high-performance systems capable of processing large PDF documents (200+ pages)- Implement AI-powered document classification using LLMs, OCR, and taxonomy-driven workflows- Design, manage, and enhance document taxonomies, classification schemas, and labeling frameworks- Develop confidence scoring, validation rules, and exception-handling mechanisms- Support multi-page document assembly and document grouping based on classification resultsBuild asynchronous processing pipelines using : 1. Background Workers2. Task Queues3. Retry Mechanisms4. Event-Driven Processing- Implement audit trails, data lineage tracking, and classification rationale logging- Integrate with Google Cloud Platform (GCP) services including : 1. Cloud Storage2. Firestore3. Cloud Tasks- Optimize infrastructure utilization and AI inference costs- Develop robust review workflows, fallback mechanisms, and automated recovery processes- Collaborate with cross-functional teams to deliver secure, scalable, and compliant document-processing solutionsRequired Skills & Experience : Backend Development : - 8+ years of experience in Python Development- Strong expertise in : 1. Python2. FastAPI3. REST APIs4. Microservices ArchitectureDocument Processing & AI : - Hands-on experience with : 1. PDF Processing2. PyPDF23. pdf2image4. OCR Systems5. Intelligent Document Processing (IDP)- Experience integrating : 1. GPT-4 Vision2. OpenAI APIs3. LLM-based Classification Models4. AI Document Understanding SystemsCloud & Infrastructure : - Strong experience with Google Cloud Platform (GCP)- Hands-on expertise in : 1. Cloud Storage2. Firestore3. Cloud Tasks4. Cloud-Native ArchitectureWorkflow & System Design : - Experience designing : 1. Asynchronous Processing Systems2. Event-Driven Architectures3. Queue-Based Workflows4. Retry Frameworks- Strong understanding of : 1. Error Handling2. Data Lineage3. Audit Trails4. Logging & Monitoring5. System ReliabilityTaxonomy & Classification : - Experience with : 1. Document Taxonomies2. Classification Frameworks3. Taxonomy Versioning4. Confidence Thresholds5. Rules-Based ValidationDomain Experience : - Experience supporting document-heavy workflows such as : 1. Loan Processing2. Credit Assessment3. Financial Services4. Compliance Platforms5. Regulatory Workflows- Knowledge of borrower document classification including : 1. KYC Documents2. Income Proofs3. Bank Statements4. Agreements5. Financial RecordsPreferred Qualifications : - Experience in FinTech, Lending, Banking, or Compliance domains- Exposure to AI-driven workflow automation- Knowledge of scalable document intelligence platforms- Experience building explainable and auditable AI systems- Familiarity with document validation and compliance frameworks (ref:hirist.tech)