Context
- Nigerian import clearance is rigged against the agent. The customs authority scores every declaration with automated valuation and risk tooling, while the clearing agent usually finds out there is a problem only when the PAAR query and the demurrage clock arrive. Nohena flips that. It lets the agent see the declaration the way a customs risk engine will, before lodgement, and fix it while there is still time. This is pro-accuracy, not evasion. Nohena prepares; the licensed agent lodges.
Approach
- A modular monolith with a separate Python AI service behind an async job pattern, so it never blocks on a government portal or a provider outage.
- RAG classification grounded in the tariff knowledge base (ECOWAS CET, WCO HS + explanatory notes, GRIs). The model never classifies from memory.
- Rules-driven valuation (WTO transaction value + Article 8 additions) and AfCFTA / ECOWAS rules of origin, each decision citing the rule.
- A two-checkpoint risk engine that predicts a four-lane outcome before lodgement, with strict per-tenant isolation and a tamper-evident audit trail.
What we built
- The pipeline: vision-LLM extraction → RAG classification → valuation-risk → origin → checkpoint/lane, behind versioned contracts.
- Four product surfaces: marketing, agent onboarding, the clearing console, and an internal review console.
- NestJS API + Python AI service on Supabase / pgvector, with an NCS CET v3 + WCO HS knowledge base (~29.5k cited chunks).
- Explainable by design: every classification, value flag, and origin call ships with a rationale, citation, and confidence.
Results
- Every decision carries a human-readable rationale, citation, and confidence. No naked verdicts.
- Queries and demurrage caught early, with a two-checkpoint, four-lane risk view before lodgement.
- A defensible, append-only audit trail that holds up under customs scrutiny.
- The lodgement boundary respected end to end: Nohena prepares, the licensed agent files.
Stack & standards
NestJSPythonSupabase / pgvectorReact + ViteRAG / Vision-LLMVertex AI
NDPA 2023Per-tenant isolationAppend-only auditEval-gated CI
“Accuracy is the product. Every classification, value flag, and origin call ships with its rationale, citation, and confidence.”
Nohena · product principle
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