Lenny's Podcast: Product | Career | Growth

Behind the product: Duolingo streaks | Jackson Shuttleworth (Group PM, Retention Team)

December 15, 2024

AI Summary

5 min read

Duolingo's streaks feature, which tracks consecutive days of lesson completion, has driven massive retention and DAUs, with over 9 million users maintaining year-long streaks. Jackson Shuttleworth, group PM on the retention team, shares the evolution from its launch as an XP-based goal to today's flexible, tested version, emphasizing over 600 experiments revealing human psychology around loss aversion, commitment, and clarity.

Core Mechanic and Early Iterations

Streaks started tied to XP goals matching daily targets, but shifted to a simple "one lesson per day" unit after tests showed it boosted DAUs without reducing meaning. A failed test lowering it to one exercise captured low-engagement users and muddled the habit unit, highlighting the need to align streaks with meaningful app usage. Clarity proved key: simple copy like "Do a day to extend your streak, miss a day and it resets" drove top retention wins by making the mechanic instantly comprehensible to global users.

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What you'll learn

1 `* (02:48) **Streaks overview and massive impact**`
2 `* (06:58) **Evolution from XP goals to one-lesson streak**`
3 `* (15:03) **Early experiments: failures and 0-7 day focus**`
4 `* (19:13) **Streak goals: iterative wins on commitment**`
5 `* (24:39) **Copy, clarity, and psych insights**`
6 `* (33:32) **Flexibility mechanics: freezes, earn-back, perfect streak**`
7 `* (46:19) **Notifications, celebrations, haptics**`

+ Full timestamped outline available in the app

Show Notes

Jackson Shuttleworth is a Group PM at Duolingo, where he leads the retention team and the powerful streak feature. The streak feature, which gamifies consecutive days of learning, has been Duolingo’s most important and innovative growth lever and a key driver of their growth to a $14 billion business with almost 600 million users. In our conversation, we dive deep into the history and lessons of this feature:

• The evolution of the streak feature

• Biggest insights from over 600 streak-related experiments

• Biggest specific wins and misses along the way

• Key principles for building effective streak mechanics

• How to operate a high-velocity product team

• Tips for building engaging notification systems

• Much more

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Find the transcript at: https://www.lennysnewsletter.com/p/behind-the-product-duolingo-streaks

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Where to find Jackson Shuttleworth:• LinkedIn: https://www.linkedin.com/in/jackson-shuttleworth/

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Where to find Lenny:

• Newsletter: https://www.lennysnewsletter.com

• X: https://twitter.com/lennysan

• LinkedIn: https://www.linkedin.com/in/lennyrachitsky/

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In this episode, we cover:

(00:00) Jackson’s background and an overview of Duolingo’s streak feature

(06:00) The impact of streaks on Duolingo’s success

(09:58) The origin and evolution of streaks

(14:50) Key experiments and insights

(24:38) User psychology and engagement strategies

(28:36) Duolingo’s product review structure

(33:07) Designing for clarity and adaptability

(46:59) Developing the Streak Freeze feature

(50:47) Balancing monetization and retention

(54:08) Notification strategies

(58:15) The Perfect Streak feature

(01:00:40) Enhancing the user experience

(01:04:47) Team operations and experimentation

(01:18:57) Who can benefit from streaks

(01:21:00) Lightning round

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Referenced:

• Duolingo streaks: https://duolingo.fandom