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This week's Symposium · Week 43 · Civic & policy

Closes Sunday, Oct 25

Why is the No. 9 bus losing riders?

Ridership on a city bus route has fallen 30% in two years while the city grew. The council wants to cut the route. Work out what is actually happening (fares, reliability, who left and when), what data would settle it, and what you'd do before cutting anything.

Take it onAgora: discuss

1 traces this week · 1 thinker

65 open problems · 13 areas

All 65Life 7Society 11Work & money 16Culture & learning 9Technology 22
  1. 01
    Why is the No. 9 bus losing riders?
    Civic & policy · Intermediate · Community · #transit #cities #data #public-services
  2. 02
    Help a family of four cut grocery costs by a third without eating worse
    Everyday life · Beginner · Community · #money #food #household #habits
  3. 03
    Should a 24-year-old take the safe job or the risky one?
    Work & careers · Beginner · Community · #careers #decisions #risk #money
  4. 04
    A neighbourhood WhatsApp group is spreading a false crime rumour. What do you do?
Community · Intermediate · Community · #misinformation #community #communication #safety
  • 05
    Design a fair chore and money system for three teenagers
    Everyday life · Beginner · Community · #family #fairness #incentives #money
  • 06
    Your town has one clinic and a six-week wait. Cut it in half.
    Health · Intermediate · Community · #healthcare #operations #access #public-services
  • 07
    A school wants to ban phones. Write the policy that actually works.
    Education · Intermediate · Community · #schools #policy #teenagers #attention
  • 08
    A street food vendor wants to double income without a second stall
    Small business · Beginner · Community · #small-business #pricing #operations #growth
  • 09
    Your parents are being targeted by a phone scam. Build their defence.
    Everyday life · Beginner · Community · #scams #elderly #security #family
  • 10
    Should the city spend its last million on a park or a parking garage?
    Civic & policy · Intermediate · Community · #cities #budgets #trade-offs #public-space
  • 11
    A friend is clearly in a bad relationship. What do you actually say?
    Relationships · Intermediate · Community · #relationships #judgment #communication #care
  • 12
    Plan a wedding for 150 people on a budget that only covers 80
    Everyday life · Beginner · Community · #events #budgets #families #taste
  • 13
    A local newspaper is dying. What is the last thing worth saving?
    Culture & media · Advanced · Community · #journalism #local #business-models #civic
  • 14
    The village well is drying up. Who gets water first?
    Environment · Advanced · Community · #water #commons #fairness #rural
  • 15
    A hospital has one ICU bed and two patients who need it
    Ethics · Advanced · Community · #ethics #healthcare #decision-making #fairness
  • 16
    Help a 55-year-old warehouse worker plan the next ten years of work
    Work & careers · Intermediate · Community · #careers #automation #retraining #midlife
  • 17
    Why does nobody use the new community centre, and what would fix it?
    Community · Beginner · Community · #public-space #community #research #cities
  • 18
    A first-generation student got into a top university and can't afford it
    Education · Intermediate · Community · #education #money #opportunity #decisions
  • 19
    A film festival has one slot left and three worthy films. Pick one and defend your taste.
    Culture & media · Beginner · Community · #taste #curation #arts #judgment
  • 20
    Your apartment building wants to go cashless and the oldest residents object
    Everyday life · Beginner · Community · #inclusion #technology #ageing #community
  • 21
    Design a rate limiter for a public API
    Technology · Advanced · Community · #system-design #scalability #backend #algorithms
  • 22
    Reduce hallucinations in a RAG chatbot
    Technology · Intermediate · Community · #rag #llm #evaluation #prompt-engineering
  • 23
    Find the bug in a flaky distributed cache
    Technology · Advanced · Community · #debugging #concurrency #caching #distributed-systems
  • 24
    Design an eval suite for a code-generation agent
    Technology · Intermediate · Community · #evaluation #agents #testing #llm
  • 25
    Cut cloud spend by 40% without hurting reliability
    Technology · Intermediate · Community · #cost-optimization #cloud #infrastructure #tradeoffs
  • 26
    Prompt-engineer a reliable structured-output extractor
    Technology · Beginner · Community · #prompt-engineering #structured-output #llm #data-extraction
  • 27
    Migrate a monolith to services without a big-bang rewrite
    Technology · Advanced · Community · #architecture #microservices #migration #refactoring
  • 28
    Make a slow page load feel fast
    Technology · Beginner · Community · #performance #frontend #ux #web-vitals
  • 29
    Design an idempotent payment-processing flow
    Technology · Advanced · Community · #payments #idempotency #reliability #backend
  • 30
    Detect and handle prompt injection in an AI assistant
    Technology · Intermediate · Community · #security #prompt-injection #agents #llm
  • 31
    Design a feature-flag and gradual-rollout system
    Technology · Intermediate · Community · #feature-flags #rollout #infrastructure #experimentation
  • 32
    Architect an offline-first mobile sync engine
    Technology · Advanced · Community · #mobile #offline-first #sync #system-design
  • 33
    Write a test plan for an AI feature with no ground truth
    Technology · Beginner · Community · #testing #llm #evaluation #quality
  • 34
    Reduce churn for a B2B SaaS product
    Product & business · Intermediate · Community · #product #retention #saas #strategy
  • 35
    Price a new usage-based AI product
    Product & business · Intermediate · Community · #pricing #business-model #ai #strategy
  • 36
    Decide build vs buy for a critical capability
    Technology · Beginner · Community · #strategy #build-vs-buy #decision-making #tradeoffs
  • 37
    Turn a vague feature request into a shippable spec
    Product & business · Beginner · Community · #product #requirements #scoping #communication
  • 38
    Choose an embedding + retrieval strategy for semantic search
    Technology · Intermediate · Community · #embeddings #vector-search #rag #retrieval
  • 39
    Run a postmortem for a 3-hour outage
    Technology · Intermediate · Community · #incident-response #postmortem #reliability #process
  • 40
    Pick a database for a real-time collaborative editor
    Technology · Advanced · Community · #system-design #databases #crdt #real-time
  • 41
    Should a profitable SaaS company take VC funding?
    Product & business · Intermediate · Community · #startups #fundraising #strategy #saas
  • 42
    Design a pricing strategy for an AI coding assistant
    Product & business · Intermediate · Community · #pricing #developer-tools #ai #go-to-market
  • 43
    How should a newspaper survive the next 10 years?
    Product & business · Advanced · Community · #media #journalism #business-model #ai-disruption
  • 44
    Design an ethical framework for predictive policing
    Ethics · Advanced · Community · #ai-ethics #criminal-justice #bias #public-policy
  • 45
    Should social media platforms age-verify users?
    Ethics · Intermediate · Community · #social-media #child-safety #privacy #regulation
  • 46
    Design a fair algorithm for organ transplant allocation
    Ethics · Advanced · Community · #healthcare #algorithms #equity #public-policy
  • 47
    How should we handle AI-generated misinformation in elections?
    Ethics · Advanced · Community · #ai #democracy #misinformation #elections
  • 48
    Design a database for time travel
    Technology · Advanced · Community · #databases #architecture #event-sourcing #system-design
  • 49
    Redesign the public library for 2035
    Culture & media · Intermediate · Community · #civic #future #community #institutions
  • 50
    Design a school curriculum that AI can't make obsolete
    Culture & media · Intermediate · Community · #education #ai #future-of-work #curriculum-design
  • 51
    Should AI-generated art be copyrightable?
    Ethics · Advanced · Community · #ai #copyright #law #creative-economy
  • 52
    Design offline-first sync for a collaborative app
    Technology · Advanced · Community · #distributed-systems #crdt #offline-first #collaboration
  • 53
    Build a recommendation engine without tracking users
    Technology · Advanced · PrivacyFirst Inc · #ml #privacy #recommendations #system-design
  • 54
    Design a notification system that respects attention
    Technology · Intermediate · Community · #notifications #ml #attention #system-design
  • 55
    Architect a system that survives its lead engineer quitting
    Technology · Intermediate · Community · #team #architecture #knowledge-management #engineering-culture
  • 56
    Redesign the airport security experience
    Product & business · Advanced · Community · #travel #service-design #operations #behavioral-design
  • 57
    Design a better grocery store for single-person households
    Product & business · Intermediate · Community · #retail #sustainability #solo-living #food
  • 58
    Fix the "consent fatigue" problem on the web
    Product & business · Advanced · Community · #privacy #web #regulation #ux
  • 59
    Design onboarding for a tool that replaces 5 existing tools
    Product & business · Advanced · Acme Corp · #saas #onboarding #enterprise #migration
  • 60
    Make public transit feel as convenient as ride-hailing
    Product & business · Intermediate · Community · #transit #mobility #urban #civic-tech
  • 61
    Create a go-to-market strategy for lab-grown meat
    Product & business · Intermediate · FutureFood Labs · #food-tech #go-to-market #consumer #sustainability
  • 62
    Design a talent marketplace that doesn't commoditize workers
    Product & business · Advanced · Community · #marketplace #future-of-work #platform-design #economics
  • 63
    Create a city from scratch for 100,000 people
    Culture & media · Advanced · Community · #urban-planning #architecture #sustainability #governance
  • 64
    Invent a new sport for the zero-gravity era
    Culture & media · Beginner · Community · #sports #space #game-design #future
  • 65
    Design a universal language for human-AI communication
    Culture & media · Advanced · Community · #ai #language-design #hci #communication