Crewchange - Crew Rotation Platform for Reliefs, Crew Changes and Certificates
Crewing Platform for a Mumbai Ship Manager
Designed and built a clickable crewing platform for a Mumbai ship manager running 45 tankers and bulk carriers: a relief timeline per vessel, a seafarer register with document status, reliefs due with proposal and approval rules by rank, and crew changes planned at a port with readiness, travel, letters and a cost sheet against budget.
Most of our work is under NDA. Per agreement, we can share the work but not the company details - all names and identifying information shown here have been changed.
Impact
Dashboard, seafarers, reliefs due, crew changes and the crew change detail, plus a New crew change panel. Each of the 13 demo crew changes opens its own detail page.
Documents, medical, visa, ticket, hotel, OK to board letter, joining instructions, briefing and signed contract, each marked done, to do, not needed or failing the joining check.
Reliefs for Master, Chief Engineer, Chief Officer and 2nd Engineer can only be approved by the crewing manager; planners approve other ranks. The approve button follows the signed-in role.
12 vessels, 19 reliefs, 13 crew changes in every status, 11 ports with their ship agents and local currency, 6 office users and seafarers from 5 countries.
The Problem
Dharamtar Crest's crewing office planned reliefs on a wall spreadsheet with one tab per vessel and tracked certificates in a second workbook that was always a week out of date. Crew changes were arranged by email with ship agents, travel agents and consulates, the true cost was only known when invoices arrived a month later, and twice in one year a seafarer joined a tanker with a flag endorsement that expired mid-contract.
Our Solution
Crewchange puts the whole crew cycle in one place: who is on which ship and when each relief is due, who can relieve them with documents valid for the full contract, and every crew change at a port with its joiners, leavers, travel, letters and cost in the port's currency and in USD against the vessel's budget.
The Challenge: Keeping 45 Ships Legally Manned
About 1,600 seafarers from India, the Philippines, Myanmar, Sri Lanka and Ukraine rotate through 45 tankers and bulk carriers under several flags. Every relief has to match the rank, the vessel type, the flag's certificate rules and a port where the crew can actually change.
Certificates That Expire Mid-Contract
Under STCW, officers need a certificate of competency for their rank, all seafarers need certificates of proficiency for their duties, and serving under another flag generally needs that flag's endorsement. Medical certificates expire too. A document valid on joining day can still lapse before the contract ends.
Reliefs Planned on a Spreadsheet
Contract lengths differ by rank, the client plans reliefs 45 days ahead, and senior officers need the crewing manager's approval. On a wall spreadsheet nobody could see which contracts had passed their end date with no relief planned.
A Crew Change Is Many Small Tasks
Each crew change needs flights, hotels, visa or transit letters, an OK to board letter, joining instructions and launch hire, arranged with a ship agent in another time zone. One missed item can leave a joiner stuck at the airport.
Placement and Data Rules From India
Indian seafarers are placed under a DGMA recruitment and placement licence, with sign-on and sign-off reported to the DGMA. Their passports, medicals and certificates are shared with agents and consulates worldwide, which the DPDP Act 2023 expects to be done with notice and a record.
Our Approach: From Crewing Rules to a Clickable Platform
Spec and Rules Research
Mapped 11 user roles, 45 screens across the crewing office, the seafarer app and the master's onboard view, and the data model for seafarers, documents, vessels, assignments, crew changes, travel, letters, cost lines, contracts, wages, allotments and rest hours. Wrote down the rules the design follows: STCW certificates and flag endorsements, MLC 2006 rest hours and employment agreements, India's Merchant Shipping Act 2025 and recruitment and placement rules, OCIMF SIRE 2.0 officer matrices and the DPDP Act 2023.
Clickable Demo on a Production UI Kit
Built 5 key screens on a production dashboard kit: the dashboard with KPIs, a 60-day relief timeline per vessel, My work by role and 12 months of crew change cost against budget; the seafarer register with a quick view panel; reliefs due with Propose, Approve and Extend panels; the crew changes list; and the crew change detail with readiness, port and agent, travel, letters, cost sheet and sign-on. Switching the demo role changes My work and who may approve.
What a Production Build Adds
Integration with flight booking through a marine travel agency, flight status, vessel positions and ETAs, the client's bank for allotment payment files, document text extraction, email, SMS, WhatsApp and push messages, and e-signature for employment agreements. Staff auth by role, an audit log of every approval, verification and data share, store-and-forward sync for the master's view, and the remaining screens: planning board, documents, compliance, training, pay, reports, settings and the seafarer app.
Why It Works: Every Relief Checked Before It Is Booked
Overdue Reliefs Show in Red
The relief timeline marks every contract ending in the next 60 days: green with a relief planned, amber inside the 45-day planning window with no relief, red when overdue. Reliefs due splits the same list into Overdue, Next 45 days, 45 to 90 days and Planned.
Proposals Checked Against the Contract
Propose seafarer ranks candidates of the right rank by vessel type experience, appraisal and document validity. Approve proposal shows each check: documents valid for the contract plus 30 days, experience on the vessel type, last appraisal, re-hire recommendation and officer pairing.
One Crew Change, One Screen
Joiners and leavers sit in one readiness grid with a done count, beside the port's agent, launch arrangements and local formalities, each person's itinerary with flight delays inline, and every letter with who it was sent to.
Cost Known Before the Invoices
The cost sheet lists air fares, hotels, transfers, agency fee, launch hire, visas, medicals and wages during travel, each in the port's currency with its exchange rate and in USD, totalled against the vessel's crew change budget.
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Global Headquarters
21 Merchant Road, 3rd Floor, Singapore 058267
Main corporate office and leadership operations
North America Office
548 Market Street, PMB 12345, San Francisco, CA 94104
Client operations and business development
India Office
402 Shivalik Shilp II, SG Highway, Ahmedabad 380015
Engineering and delivery center
Enterprise Software Engineering - Human + AI
Contact Us
Locations
Global Headquarters
21 Merchant Road, 3rd Floor, Singapore 058267
Main corporate office and leadership operations
North America Office
548 Market Street, PMB 12345, San Francisco, CA 94104
Client operations and business development
India Office
402 Shivalik Shilp II, SG Highway, Ahmedabad 380015
Engineering and delivery center
© 2026 - Copyright. All Rights reserved Oceanlab