We are seeking an experienced and highly reliable Python developer to design, build, deploy, and fully document a mission-critical data ingestion service for a classified governmental traffic enforcement system. This is a turnkey project: the selected developer must deliver complete source code, full implementation on the target infrastructure, comprehensive documentation, and all materials necessary for long-term independent operation by our team. This is a production-grade, government-grade system. Zero data loss is an absolute requirement. The software must be robust, fault-tolerant, and battle-tested. Partial uploads, missed incidents, silent failures, or any form of data corruption are unacceptable. Every incident must be captured, processed, and stored with full integrity — no exceptions. Project Overview The service receives incident event data from an external traffic enforcement camera system and assembles standardized, tamper-evident evidence packages for secure storage in an AWS S3 bucket. Incident metadata and still images arrive over HTTP as JSON payloads. Related video clips are delivered separately via FTP. The system must correlate FTP video files with the correct incident, normalize all metadata into a required output JSON schema, bundle everything into a single ZIP package per incident, and upload it to S3 under a defined key structure. The service will run continuously as a background process on an AWS EC2 instance running Debian 13. Scope of Work Build a lightweight but hardened HTTP receiver in Python to accept incident JSON payloads and associated still images. Implement FTP intake to collect video clips and associate them with the correct incident using agreed-upon identifiers or naming conventions. Parse and normalize incoming metadata into a strictly defined output JSON schema. Create a ZIP archive per incident containing the normalized JSON, received images, and matched video files. Upload each ZIP package to AWS S3 using a defined object key structure. Implement comprehensive logging, error handling, retry logic, deduplication safeguards, and integrity checks to guarantee that no incident is lost, duplicated, or partially processed. Provide a production-ready deployment and configuration approach tailored for Debian 13 on EC2. Critical Reliability Requirements Given the governmental and classified nature of this project, the following are non-negotiable: the system must implement atomic or transactional upload behavior to prevent partial or corrupt packages from reaching S3; all operations must be fully logged with sufficient detail for auditing and incident reconstruction; retry logic must cover all network-level and service-level failures; the system must detect and handle duplicate deliveries gracefully; any unrecoverable failure must trigger alerts and preserve the raw input data for manual reprocessing; no data may be silently dropped under any circumstance. Technical Requirements Python 3.x. AWS S3 integration using boto3 or equivalent. FTP file intake, either standalone or integrated with an existing FTP server on the host. Runs as a persistent background service on Debian 13 using systemd. Configuration via environment variables or a structured config file. Secure handling of all credentials and network endpoints. All sensitive project details shared under NDA. Turnkey Deliverables Complete, well-structured source code with setup, configuration, and execution instructions. Full documentation covering HTTP endpoint usage, FTP intake strategy, normalization logic, and S3 upload configuration. Deployment guide and runbook for operation on EC2 Debian 13. Unit and integration tests, plus a validation plan to confirm correct end-to-end behavior before handover. Handover session and notes to ensure the operating team can maintain and extend the system independently. All intellectual property, source code, and documentation become the exclusive property of the client upon final delivery. When Applying Please include concrete examples of similar Python backend services you have built, particularly those involving AWS S3, FTP workflows, media or file packaging pipelines, and production-grade reliability. Experience building services for government, law enforcement, or other regulated environments is a strong advantage. Candidates who cannot demonstrate robust, production-tested work will not be considered.