We are building an FMCSA-compliant Electronic Logging Device (ELD) system and need an experienced developer to implement ELD data transfer via Email and Web Services, strictly following the FMCSA ELD Interface Control Document (ICD) Attached in the job post. This task focuses primarily on Section 3.2 – ELD Email Interface, with coordination to Web Services (Section 3.1) where required. The implementation must be fully compliant, testable using FMCSA test credentials, and ready for FMCSA validation. Scope of Work 1. ELD Email Interface (Primary – Section 3.2) Implement secure ELD data submission via S/MIME encrypted email Encrypt emails using AES-256 with the FMCSA public key Digitally sign emails using the manufacturer/provider private key Construct email headers exactly as per FMCSA specs: Subject formats: ELD records from <ELD Registration ID>:<ELD Identifier> TEST: ELD records from <ELD Registration ID>:<ELD Identifier> ELD ping from <ELD Registration ID>:<ELD Identifier> Attach ELD output CSV file as per FMCSA file format rules Handle and parse FMCSA email responses: Validation status Submission ID Error list Diagnostic responses 2. Web Services Interface (Supporting – Section 3.1) Implement SOAP 1.2 client for FMCSA ELD submission (if required) Mutual TLS using provider certificate Support: Submit ELD file Ping / diagnostic request Proper handling of test vs production flags 3. Compliance & Validation Ensure strict compliance with FMCSA rules: Line Data Check (LDCV) File Data Check CR-only line delimiters ASCII encoding Validate against FMCSA File Validator Handle FMCSA error scenarios (expired certs, signature failure, decryption errors, etc.) 4. Deliverables Working implementation (Java Spring boot/ Or we can use Node for now) Configuration for certificates and keys Clear setup and run documentation Sample test submission flow with FMCSA test credentials Required Skills & Experience: Strong experience with FMCSA ELD compliance Hands-on with S/MIME, PKI, digital certificates Email encryption/signing (AES-256, RSA/ECDSA) SOAP 1.2 and XML Understanding of ELD CSV format and validation rules Prior experience with FMCSA, DOT, or ELD systems is a big plus