Engineering articles from Duolingo
AI summaries and key learnings from Duolingo engineering teams.
Solving database contention with optimistic locking
The article explores the challenges of database contention in the context of the Duolingo app's notification system, which faced delays due to locking issues during high traffic. It details the...
Automating Golden Path upgrades at scale: A journey from manual upgrades to an AI-powered workflow
The article outlines a project undertaken by the Engineering Studio team to automate the upgrade process of multiple Java services to adhere to a defined 'Golden Path' of technology standards. By...
Agentic Workflows: Scale AI Prompts Beyond Cursor—No Code Required
The article introduces 'agentic workflows' at Duolingo, designed to streamline the creation and deployment of AI-driven coding agents for routine tasks. These workflows enable users, including...
Building an AI Agent to Remove Feature Flags
The article outlines the creation of an AI agent designed to automate the removal of feature flags at Duolingo, leveraging Temporal for workflow orchestration and Codex CLI for AI-driven code...
2025 Duolingo Highlights: our biggest leaps in learning, play, and connection
In 2025, Duolingo made significant strides in enhancing its platform, introducing a variety of new features and courses aimed at improving user engagement and learning outcomes. Notably, the launch...
Dear Duolingo: How do I support someone who’s learning a language?
The article provides advice on how to support someone who is learning a new language. Dr. Emilie Zuniga offers five practical tips for being a supportive language-learning companion: allowing the...
The 2025 Duolingo Social Impact report
The article discusses Duolingo's efforts to support early childhood education in Pennsylvania amid significant funding cuts. The company launched the Early Learners First Program, investing $1...
7 ways you can switch up your practice in the app right now
The article presents various engaging methods for users to enhance their language learning experience on Duolingo. It outlines seven distinct lesson types that cater to different learning styles,...
Is it Hanukkah or Chanukah? The language behind the Festival of Lights
The article explores the cultural and linguistic aspects of Hanukkah, a significant Jewish holiday celebrated annually in December. It provides a brief historical context, highlighting the victory of...
3 ways to form questions in French
The article provides a comprehensive overview of how to form questions in French, highlighting three primary methods: using a change in intonation, the phrase 'est-ce que', and inversion. Each method...
What’s the best way to learn with Duolingo?
The article discusses how to effectively use Duolingo, a popular language-learning platform, to master a new language. It emphasizes that learning a language requires significant time and effort, and...
Our new Video Call with Falstaff is here to help you speak with confidence
The article introduces a new feature from Duolingo called 'Video Call with Falstaff', designed to enhance language speaking practice through real-time coaching. Unlike the previous 'Video Call'...
2025 Duolingo Language Report
The 2025 Duolingo Language Report analyzes the latest trends in language learning based on data from millions of users globally. The report highlights an unprecedented interest in language education,...
Dear Duolingo: How does a word’s meaning change over time?
The article from Dear Duolingo explores the fascinating phenomenon of language change, specifically how words evolve over time in meaning. It discusses various mechanisms through which this change...
The 7 most common types of English adverbs
This article serves as a comprehensive guide to adverbs in the English language, detailing their definition, types, and usage. Adverbs are words that modify verbs, adjectives, and other adverbs,...
20+ English adverbs of degree to show how much you mean it
The article provides a comprehensive overview of adverbs of degree in English, explaining their role in modifying verbs, adjectives, and other adverbs. It categorizes these adverbs into three groups:...
Strengthen your memory with new Duolingo Flashcards
The article introduces a new feature in language learning that utilizes flashcards to enhance active recall and memory retention. This feature helps learners practice word translations by requiring...
Dear Duolingo: Do all languages have slang?
The article discusses the significance and functionality of slang in language, illustrating how it serves to create social groups and express identity. It highlights the universal nature of slang,...
How 5 companies turn language learning into connection and growth
The article discusses how organizations across various industries are leveraging Duolingo for Business to enhance communication, foster inclusion, and drive career growth among employees through...
Explain My Answer is now free for all learners!
Duolingo has made its popular in-lesson feedback feature, 'Explain My Answer,' available for free to all learners. Originally a feature for Duolingo Max subscribers, it provides personalized tips and...