duolingo

Build the team the way Duolingo built theirs — the Green Machine operating model, talent density over headcount, candor protocol ("focus on what, not who"), hire-slow / fire-fast, and the "no process unless it makes decisions better" rule. Use when the user is hiring, defining team rituals, debating remote vs. office, choosing a feedback model, or installing an operating system in a team that has none. Source the Duolingo Handbook (Raise the Bar + Green Machine).

UI patterns from the Duolingo design system — juicy motion, the character system as the emotional channel, design tokens (color/type/spacing), sound as a UX surface, accessibility as a default not a checklist, and "error-as-delight" detailing. Use when the user is designing a screen for a gamified or learning product, reviewing a design for "why does this feel flat," picking a motion system, building a character mascot, or auditing for accessibility. Source the Duolingo design system at design.duolingo.com.

Duolingo-style experimentation as a decision protocol — hundreds of A/B tests a week, opinions resolved by data, ideas killed quickly. Covers hypothesis design, metric selection, guardrails, sample size, novelty effects, and explicit kill criteria. Use when the user wants to run an A/B test, decide between two designs without arguing, set up an experiment program, debug why a test isn't moving, or build a culture where "show don't tell" replaces seniority-based decisions. Source the Duolingo Handbook (Show Don't Tell) and engineering blog posts.

Add Duolingo-style play to any product — XP systems, juicy feedback, leagues, celebration moments, hearts/energy, and the anti-grind discipline that keeps gamification from turning toxic. Use when the user asks how to make a product fun, addictive, or "feel like a game," when designing rewards, levels, or progress, or when an existing system feels like a slot machine and they want it to feel like a craft. Source the Duolingo Handbook (Make It Fun) and the Duolingo design system.

Duolingo-style growth that doesn't break retention — viral loops, brand-as-acquisition (the TikTok playbook), referral mechanics, localization as a growth lever, and the founder-mode marketing that turned a mascot into a meme. Use when the user is planning acquisition, building a referral system, considering paid vs. organic, evaluating a marketing channel, or trying to turn an existing brand into a growth engine. Source the Duolingo Handbook (Make It Fun) and observed marketing patterns from 2022–2025.

Make product decisions the way Duolingo does — long-view over short-term, ruthless prioritization, ship-and-learn over plan-and-ship, dogfooding, and the "intuitive by default" quality bar. Use when the user is roadmapping, deciding what to cut, debating whether to ship, defining a quality bar for a feature, or trying to install a "product-led" culture in a team that defaults to feature factories. Source the Duolingo Handbook principles 1, 2, and 3 (Take the Long View, Raise the Bar, Ship It).

Duolingo-style retention engineering for any product — habit loops, streaks, leagues, churn diagnostics, day-N drop-off, and the discipline of building a "forever product." Use when the user asks how to keep users coming back, debug churn, design a streak system, time push notifications, run a leaderboard, or shift a product's metric from acquisition to retention. Source the Duolingo Handbook (Take the Long View) and blog data posts; translate every pattern to the user's actual product.

Write product copy in the Duolingo voice — "wholesome but unhinged," character-driven, screenshot-worthy. Covers push notifications, error states, onboarding, empty states, celebrations, and the now-famous threat-copy that turned a green owl into a meme. Use when the user is writing any user-facing string — notifications, microcopy, errors, marketing — and wants it to feel like a person, not a product. Source the Duolingo Handbook (Make It Fun) and observed blog/marketing patterns.