A working, multi-tenant operations system for owners running 3,000–80,000 DWT dry bulk tonnage on spot voyage charters. Built by someone who stood the watches the software now accounts for. Live in production; 231 automated tests.
A four-to-eight person office runs the fleet from spreadsheets and chat threads. Certificate expiries are tracked by memory, laytime is recalculated by hand for every dispute, and nobody can say what a voyage actually earned per day until weeks later.
The design rule for every screen: if an operation takes longer here than it does in Excel, the screen is wrong. Quick SOF entry, one-click alert actions, paste-an-email extraction — speed is a feature requirement, not a nice-to-have.
Noon report → fuel reconciliation → bunker cost. Agent DA (proforma vs final) → port costs. Statement of Facts → GENCON laytime → demurrage or despatch. All three feed one voyage P&L, per vessel, per day.
Crew documents and ship certificates are watched by an alert engine whose thresholds are derived from per-flag lead times stored in a table — a Panama endorsement that takes 45 days to issue raises its first alert 75 days out. A fourth flag is a table row, not a release.
The GENCON engine (SHINC/SHEX/WWD, reversible, half despatch) stores its full input and rule set with every calculation, so the same calculation gives the same answer six months later in a dispute. Statements export as PDF and Excel, in charterer-facing English.
Paste the master's noon report email; a rule-based parser (Turkish and English) pre-fills the form — and never writes a record itself. The person reviewing keeps the last word, and unreadable fields are flagged, not guessed.
Tenant scoping is enforced at SQL compile time; every model ships with a mandatory cross-tenant isolation test. Money is Decimal with an explicit currency; every quantity carries its unit; ship-local timestamps are stored beside UTC and never trusted for ordering.
Nothing is physically deleted. Every renewal, alert action and cost fill lands in an append-only event log the application role cannot update or delete — the office can always answer “who changed this, and when?”
Nightly reconciliation catches anything the write path missed. Daily database and file backups are pulled off-site automatically, and a monthly restore drill proves the backups actually restore — it has already caught one empty dump.
Every laytime rule is pinned by a golden test against a hand-verified Statement of Facts — and golden tests are never “fixed” by updating the expected value. Extraction samples are pinned the same way.
What the product deliberately does not do — no stability calculations, no bunker planning, no emissions reporting yet — is documented as binding scope, so features enter through a decision, not through drift.
Ten years at sea as a deck officer, ending as chief mate: NOR clauses, SOF interruptions and flag-state paperwork are modelled from practice, not from a textbook.
Python 3.12, Django 5, PostgreSQL 16, HTMX — server-rendered, fast on bad connections. Docker Compose behind an nginx proxy with automatic TLS. One external Python dependency beyond the framework stack.
Phase 0 (core engines) and Phase 1 (full office workflows) are closed and tagged; Phase 2 (noon reports, DA tracking, extraction) is live. Every work package landed with tests green and deployed the same day.
Running at app.zdeck.tech with monitoring, backups and a seeded demo fleet. Next step: one real office, one month, their Excel retired.
Engineering notes: Two walls, not one — Postgres row-level security under the ORM · Golden tests for laytime — why the expected value is never updated. The laytime engine is open source: github.com/oktaybobus/laytime. Need a statement rather than a system? Laytime statement in 24 hours.
Ask for a walkthrough — or bring one voyage and we will enter it together.