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The Carnival Launch & The Omicron Spike

The Carnival Launch & The Omicron Spike
Project Date2026-01-30
Tech Stack
CamundaAWS TextractAWS SQSHeuristic Optimization

#Context

Verifly served as the primary digital health pass during the pandemic, automating compliance checks to prevent massive bottlenecks at airports and seaports. I led the critical B2B integration with SeaCare, the medical clearance platform used to relaunch operations for Carnival Cruise Line and Viking.

#Problem

Following a landmark contract win with Carnival, we faced an immovable target: the high-profile return to sea of the flagship Mardi Gras at Port Canaveral, Florida on Saturday, January 22, 2022.

The timeline was aggressive, but the timing was worse. As we sprinted to build the integration, the global holiday travel season was beginning. We were walking into a perfect storm of technical constraints.

Integration Velocity

We needed to integrate with SeaCare's external APIs rapidly. The timeline was fixed, and the technical requirements for the cruise line manifests were complex. Failure here meant the ship simply couldn't sail.

The Global Travel Exploded

General air travel didn't just recover—it skyrocketed. According to IATA market data, international passenger traffic (RPKs) jumped +79.1% in December 2021 compared to the previous year. We were suddenly processing nearly double the volume of travelers with the same size team.

New Omicron Rules

US government slashed testing windows from 72 hours to 1 day to combat Omicron. This triggered a global chain reaction. Passengers flying to the USA suddenly had 66% less time to get verified, causing a massive spike in panicked user errors.

IATA Data showing International RPKs rising from ~14% of normal levels (Jan 2021) to ~42% (Dec 2021)—a near tripling of active volume throughout the year.

CDC Press Release (Dec 6, 2021): "Effective December 6, all air passengers... must show a negative COVID-19 test taken no more than 1 day before travel.

CDC press release

#Strategy

To manage the massive holiday load while meeting the Carnival deadline, I implemented a strategy focused on prioritization, caching, and synchronization.

#1. Monetizing the Traffic Surge

I engineered a Premium Users Priority System to handle the surge. Instead of a standard FIFO model, I built a logic-based queue that allowed paid users to "cut the line." This monetized the high demand while ensuring critical passengers were processed first.

#2. Targeted AI & OCR Optimization

I prioritized country-specific OCR tuning for our highest-volume routes, drastically improving data matching rates. I also connected our internal AI tool to a feedback loop: every time a human corrected a document, that data retrained the model, increasing automation daily.

#3. Cryptographic Hashing

I implemented cryptographic hashing to fingerprint every file. If a document was verified once, we cached that decision. Any subsequent upload of the same file was instantly auto-approved, cutting duplicate work by ~30% and clearing the queue.

#4. Bidirectional Integration & Coordination

I architected a bidirectional integration with SeaCare, ensuring our systems "talked" in real-time to keep medical statuses synced. Simultaneously, I led the technical coordination with Carnival’s operations team, aligning our engineering efforts to land the pilot launch on time.

#Impact

The pilot was so successful that Carnival didn't just keep it—they scaled it. By March 2022, Carnival adopted VeriFLY across its entire US fleet, rolling it out to all 20+ ships and all homeports.

  • Adoption: Over 85% of guests downloaded VeriFLY ahead of time, proving the "Fast Track" value proposition worked.
  • Speed: The automated flow cut check-in times by 50%, allowing thousands of passengers to board in record time.
  • Validation: Following this success, Carnival rolled out the solution fleet-wide to all US ships, processing over 1 million guests within months.
  1. Carnival Press Room: Carnival Launches VeriFLY Digital Wallet Fleetwide
  2. Pax News: One million Carnival guests have used VeriFLY

While the Carnival pilot was our focus, our existing airline partners (American Airlines, British Airways) were hit by a historic travel spike.

  • The Load: Over 109 million travelers took to the skies and roads during the 2021 holiday season, with air travel increasing 184% compared to 2020.
  • The Resilience: Despite the traffic nearly tripling and testing windows shrinking to 24 hours, our "De-Dupe" caching and priority queues held firm. The system processed the unprecedented volume without a single critical outage.
  1. AAA Newsroom: 2021 Year-End Holiday Travel Forecast

#Reflection

Looking back, this project was a masterclass in high-stakes agility. The requirements didn't just change; they evolved daily as global regulations shifted. Yet, instead of chaos, we found a rhythm. Working under such tight deadlines with a brilliant team and a supportive CTO turned a pressure cooker into one of the most fulfilling experiences of my career. There is a unique satisfaction in shipping code on Friday and seeing it help thousands of families board their dream vacation on Saturday. It proved that with the right team and the right strategy, even a "perfect storm" is navigable.

Filip Zobic

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