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Immersive Handbook
Home
Engineering
Runbooks
AWS services
Agent Autonomy Policy
Claude Code in Slack (agent loop)
DNS Management
Kamal Deployment (Hetzner)
MailerSend Configuration
Manual test plan
Rake Tasks Documentation
Rate limiting
Secrets Management
Conventions
CSS Best Practices
Design Review Process (#457)
Design Workflow: Claude Code ↔ GitHub ↔ Claude Design
Engineering Project Board
Fake AI backends in development
Icons
LLM Prompt Architecture (RubyLLM)
Prompt Generator
SEO Implementation Guide
Shared Partials
Testing
Architecture
API
Anki Deck Export
Anki Sync Integration
Background Jobs
Caching
Platform Notes
PostgreSQL
StudyEvent + UserAbility System
Verb Architecture
Features
Admin Dashboard
Bookmarks
Categories
Conjugation Sentence Matching
Contact and Feedback
Cross-language conjugation comparison (#414)
Documents Feature
Email Subscriptions
Email Tracking
FSRS Spaced Repetition System
Frequency starter decks
Grammar Admin Guide
Grammar Notes
Grammar of Reading
Knowledge Base
Resource Audio
Review Card: Design and Behavior Spec
Sticky Settings
User Invitations
User Locking and Banning
User Profiles and Account Settings
Verb Page Examples
Verb Sentence Matching System
Verb Validator
Mobile
Hotwire Native Guide
Hotwire Native Reference
Product
Immersive Redesign and Extension Design
Product Specification
The Bridge Method
Marketing
Immersive Business and Growth Plan
Operations
Billing and Accounts
Research
AI Agents Running a Company
AI Agent Wipes Production Database, Then Lies About It
AI Incident Database, Incident 1152: LLM-Driven Replit Agent Reportedly Executed Unauthorized Destructive Commands During Code Freeze
AI agents could birth the first one-person unicorn - but at what societal cost?
Duolingo went 'AI-first' and then came the consumer backlash
Full Disclosure, Less Trust? How the Level of Detail about AI Use in News Writing Affects Readers' Trust
How Anthropic teams use Claude Code
How Pieter Levels Makes $3.2M/Year With A Laptop and No Employees
How we built our multi-agent research system
Human-in-the-Loop Review Workflows for LLM Applications and Agents
LLM Cost Optimization Techniques: A Production Playbook
Project Vend: Phase two
Solo founders are using AI to do the work of entire teams - but going it alone has limits
The lethal trifecta for AI agents: private data, untrusted content, and external communication
When to use multi-agent systems (and when not to)
Competitor Analysis & Market Gaps
Beelinguapp Review 2025: Bilingual Reading & Audiobooks
Busuu Review 2026 (Is This Language App Effective?)
Clozemaster Review: Limited Focus But Fun Way To Grow Vocab
Duolingo Q1 2026 Earnings: DAUs Hit 21% Growth, EBITDA Margin Reaches 29%
EuroComDidact - Welcome (EuroComDidact ToGo app)
How Much Is Super Duolingo in July 2026? Family Plan Cost & More
I'm finally quitting Duolingo after this change (energy system)
In defense of Anki, a response to Luca Lampariello
Intercomprehension - Wikipedia
Is Babbel Worth It in 2026?
Language Learning App Market Size, Share | Forecast Report [2033]
LingQ Review - Extensive Reading Made Easy
Lingvist Review: Price, Pros and Cons, and the Best Alternatives
Memrise is Doing Away with User-Generated Content... Now What?
Migaku Review: Can Immersion Tools Teach Japanese? (2026)
Pimsleur vs Rosetta Stone (Which App Is Better?)
Readlang Review: A Decent Assisted Reader But Could Be Better
Reverso (language tools) - Wikipedia
Marketing & Advertising Research
ASO Case Study: How a Language Learning App Achieved Top 5 Ranking in 8 Months
Duolingo's Scaling Journey: Education Revolution or Engagement Obsession?
Hacker News Marketing for Developer Tools: Show HN, Launch Day, and Sustained Coverage
How Vancouver-based language app LingQ evolves in a changing market
IXL Learning Acquires Language Learning Software Developer Curiosity Media
Language Learning App Statistics By Usage, Market Size, Revenue, Download, Age and Facts (2025)
Launched on Reddit and it's becoming a disaster
Lead Magnet Conversion Benchmarks 2026: B2B Data Guide
Lifetime Deals on AppSumo: Worth It or Revenue Killer?
Positioning Jujitsu - How to Win Against Powerful Competitors (April Dunford)
Preply Programmatic SEO Case Study: 8x Organic Traffic in 50 Languages
Product Hunt Launch Statistics for 2026: Platform Scale, Featured Rate, Traffic, Conversion, SEO, Upvotes, and Case Studies
Refold - Guiding language learners to unlock their full potential (Patreon)
State of Subscription Apps 2025
The State of Subscription Apps in 10 minutes: lessons, trends, and benchmarks for 2026
Product history
Dashboard analytics improvements
Grammar notes: Bridge Method audit (#413)
Proposed additional analytics metrics
Starter-content tracker (2026-07 snapshot)
SLA Research
A Stochastic Shortest Path Algorithm for Optimizing Spaced Repetition Scheduling
Common European Framework of Reference for Languages: Learning, teaching, assessment - Companion Volume
Distributed Practice in Verbal Recall Tasks: A Review and Quantitative Synthesis
Effectiveness of L2 Instruction: A Research Synthesis and Quantitative Meta-analysis
EuRom5 - Lire et comprendre 5 langues romanes (Hoepli 2011)
How Large a Vocabulary Is Needed For Reading and Listening?
Intercomprehension - A Mere Dream or a New Way of Learning in Globalised World?
L2 grit and age as predictors of attrition in mobile-assisted language learning
Miriadi - Projects (Galatea, Galanet, Galapro, Redinter lineage)
SRS Benchmark (open-spaced-repetition)
Supplemental_instruction
The Effects of Repetition on Incidental Vocabulary Learning: A Meta-Analysis of Correlational Studies
The Effects of Spaced Practice on Second Language Learning: A Meta-Analysis
The MOOC Pivot
The effectiveness of ER on reading proficiency: A meta-analysis
The lifespan development of cognate guessing skills in an unknown related language
Unknown Vocabulary Density and Reading Comprehension: Replicating Hu and Nation (2000)
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