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The New York Times Ships the First Commercial Flutter Web App in Six Weeks

Try it
Play the full puzzle

A working prototype built in 48 hours became a production-quality app running on six platforms from a single codebase.

Client

Google x The New York Times

Media & publishing  /  Application development
6 Weeks to global debut
2M+ Monthly solvers
#1 Commercial Flutter Web app
6-in-1

iOS / Android / macOS / Windows / Web / Mobile Web

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The Problem

Puzzles are not a side feature at The New York Times. At the time of the project, the Crossword alone had more than 400,000 standalone subscriptions, and the digital puzzle portfolio reached more than two million solvers each month. Games were one of the company’s strongest engines for subscriber growth and engagement beyond news.

One of those games had a problem. KenKen, a popular number puzzle, was built in Adobe Flash, a platform at the end of its life. Rebuilding it the conventional way meant separate codebases for every platform NYT’s solvers used, with all the cost and drag that implies.

Google had a parallel need. Flutter for Web was approaching its first public technical preview, and the team wanted a real commercial product to prove it on the Google I/O stage. That meant a fixed, very public deadline and no room for a rough edge.

400K+ Standalone Crossword subscriptions
2M+ Monthly solvers, digital puzzle portfolio
“Discovering that they could reach the web with the same code was a huge boon.”
Google Flutter team
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The Approach

“We only had 48 hours to build a working prototype that would validate its feasibility, and we happily accepted the challenge!”
Martin Rybak, Very Good Ventures
48H To a working prototype

The engagement started with a phone call. Google’s Tim Sneath asked VGV to build a demo app for The New York Times that would run on mobile, desktop, and web.

A

KenKen as the flagship

A recognizable, engaging puzzle already in NYT’s portfolio, contained enough to ship fast and visible enough to matter.

B

One codebase, six targets

iOS, Android, macOS, Windows, Web, and mobile Web, with no forked platform builds.

C

Responsive design with per-platform polish

Touch on mobile, mouse and keyboard on desktop, and layouts that scaled to every form factor.

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The Results

On May 7, 2019, the KENKEN app debuted in the Google I/O technical keynote as the first commercial Flutter Web app. Six platforms shipped from one codebase, roughly six weeks after kickoff, in front of a global developer audience.

One codebase  /  six targets  /  six weeks
The New York Times KENKEN puzzle app running in a desktop browser next to the same puzzle on a phone, built with Flutter.
The KENKEN puzzle app running in mobile Safari on iPhone, showing the nytimes.com address bar.
The KENKEN puzzle app running as a native iOS app built with Flutter.
The KENKEN puzzle app running as a native Android app built with Flutter.
6 Platforms, one codebase
“The New York Times KENKEN app prototype does exactly what Flutter has always promised — it delivers a beautiful, performant native experience from a single codebase. And that now includes the Web, whether using a desktop or a mobile browser.”
David DeRemer, co-founder, Very Good Ventures
Delivery engine

Why six weeks produced a product, not a demo

A CI/CD pipeline kept builds stable across all six platforms, and Firebase Hosting let stakeholders review changes in minutes instead of waiting on app store cycles.

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Play it

4 × 4  /  easy 00:00

Solved it.

That is the same puzzle NYT solvers played in 2019, running on the same stack we built it on.

Built in Flutter Web

Same stack as the 2019 app. Every row and column holds 1 to 4 once, and each outlined cage has to hit its target.

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The Impact

The pilot converted

In mid-2020, after successfully piloting Flutter, The New York Times added Flutter to their primary games app, bringing the approach proven on KENKEN into the platform at the center of their games strategy, and into the daily habit of an audience measured in the millions.

The KENKEN puzzle app win screen reading KEN-gratulations above a completed four by four grid.
Mid-2020

Flutter enters NYT’s primary games app

The one true conversion outcome of the engagement, and the reason the keynote was a beginning rather than an end.

Beyond the keynote

KENKEN became the reference proof that Flutter could carry a commercial product on the web.

1 Codebase reaching every platform they played on
“The New York Times Crossword has more than 400,000 stand-alone subscriptions and is a daily ritual for puzzle solvers. Along with the Crossword, we’ve grown our portfolio of digital puzzles that reaches more than two million solvers each month. We were already beginning to explore Flutter as a potential solution to the challenge of quickly developing engaging, high-quality mobile experiences. Now the addition of being able to publish to web makes Flutter an even more appealing option to quickly deploy across all of our user platforms. This update of our old Flash-based KenKen game into a multi-platform playable experience is something we’re excited to bring to our solvers this year.”
Client voice

Eric von Coelln

Executive Director of Puzzles

The New York Times

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