Public task directory

Technical interview practice tasks

Every entry below is a crawlable link to a unique public task page. This directory complements the interactive filters and keeps the complete catalog connected through standard pagination.

Page 364 of 386 · 18,491 tasks

SQL Case · Medium · 30 min

Return each candidate’s most recent application

Return each candidate’s most recent application.

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SQL Case · Hard · 45 min

Build an application-cohort funnel by application month

Build an application-cohort funnel by application month.

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SQL Case · Easy · 20 min

Find candidates who applied to more than one distinct role

Find candidates who applied to more than one distinct role.

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SQL Case · Easy · 20 min

Calculate offer acceptance rate for each role

Calculate offer acceptance rate for each role.

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SQL Case · Easy · 20 min

Count open applications for each recruiter, excluding hired and rejected applications

Count open applications for each recruiter, excluding hired and rejected applications.

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SQL Case · Hard · 45 min

Compare application volume, offer rate, and hire rate by candidate source

Compare application volume, offer rate, and hire rate by candidate source.

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SQL Case · Medium · 30 min

Calculate positive recommendation rate by interview stage

Calculate positive recommendation rate by interview stage.

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SQL Case · Medium · 30 min

Measure elapsed days from application to offer

Measure elapsed days from application to offer.

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SQL Case · Hard · 45 min

Create one billing-health row for every account

Create one billing-health row for every account.

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SQL Case · Easy · 20 min

Sum monthly recurring revenue from active subscriptions

Sum monthly recurring revenue from active subscriptions.

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SQL Case · Easy · 20 min

Find accounts with at least two overdue invoices

Find accounts with at least two overdue invoices.

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SQL Case · Medium · 30 min

Measure average days to pay for paid invoices in each account segment

Measure average days to pay for paid invoices in each account segment.

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SQL Case · Medium · 30 min

Return the most recently started subscription row for each account

Return the most recently started subscription row for each account.

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SQL Case · Hard · 45 min

Calculate the net monthly-price change introduced by subscription starts and cancellations

Calculate the net monthly-price change introduced by subscription starts and cancellations.

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SQL Case · Medium · 30 min

Find accounts whose latest monthly price is higher than their previous subscription price

Find accounts whose latest monthly price is higher than their previous subscription price.

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SQL Case · Medium · 30 min

Calculate each account’s share of all paid invoice revenue

Calculate each account’s share of all paid invoice revenue.

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SQL Case · Easy · 20 min

Calculate licensed-seat utilization for each account

Calculate licensed-seat utilization for each account.

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SQL Case · Easy · 20 min

List invoices that have not been paid

List invoices that have not been paid.

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SQL Case · Hard · 45 min

Find services with at least two consecutive metric windows above a 2% error rate

Find services with at least two consecutive metric windows above a 2% error rate.

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SQL Case · Medium · 30 min

Find windows where error rate exceeded 3% or p95 latency exceeded 500 ms

Find windows where error rate exceeded 3% or p95 latency exceeded 500 ms.

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SQL Case · Easy · 20 min

Count successful and rolled-back deployments for each service with deployments

Count successful and rolled-back deployments for each service with deployments.

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SQL Case · Medium · 30 min

Estimate how much of a 1% error budget each service consumed across the observed windows

Estimate how much of a 1% error budget each service consumed across the observed windows.

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SQL Case · Easy · 20 min

Calculate aggregate request error rate for each service

Calculate aggregate request error rate for each service.

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SQL Case · Easy · 20 min

Calculate mean resolution time for resolved incidents by severity

Calculate mean resolution time for resolved incidents by severity.

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SQL Case · Easy · 20 min

List incidents that have not been resolved

List incidents that have not been resolved.

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SQL Case · Medium · 30 min

Match incidents to the latest deployment of the same service in the previous two hours

Match incidents to the latest deployment of the same service in the previous two hours.

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SQL Case · Hard · 45 min

Build one reliability summary row for every service

Build one reliability summary row for every service.

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SQL Case · Medium · 30 min

Rank services within each tier by aggregate error rate

Rank services within each tier by aggregate error rate.

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SQL Case · Medium · 30 min

Rank agents by resolved-ticket count within their team

Rank agents by resolved-ticket count within their team.

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SQL Case · Easy · 20 min

Calculate average satisfaction for ticket categories with survey responses

Calculate average satisfaction for ticket categories with survey responses.

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SQL Case · Easy · 20 min

Calculate minutes from ticket creation to the first agent reply

Calculate minutes from ticket creation to the first agent reply.

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SQL Case · Easy · 20 min

Count currently open tickets by priority

Count currently open tickets by priority.

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SQL Case · Medium · 30 min

Count reopen events for every ticket that was reopened

Count reopen events for every ticket that was reopened.

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SQL Case · Medium · 30 min

Find customers who opened tickets on at least two distinct calendar days

Find customers who opened tickets on at least two distinct calendar days.

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SQL Case · Hard · 45 min

Measure average and maximum resolution hours for resolved tickets in each category

Measure average and maximum resolution hours for resolved tickets in each category.

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SQL Case · Medium · 30 min

Find high or urgent tickets whose first agent reply took more than 120 minutes, including tickets with no reply

Find high or urgent tickets whose first agent reply took more than 120 minutes, including tickets with no reply.

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SQL Case · Hard · 45 min

Build one operational summary row per ticket

Build one operational summary row per ticket.

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SQL Case · Easy · 20 min

List open tickets that have no assigned agent

List open tickets that have no assigned agent.

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Coding (Platform) · Hard · 70 min

Resolve Checkout Conflicts

Workspace: react Difficulty: Hard Time: 70 minutes Context A support agent edits quantities in an existing checkout while another operator can change the same order on the server. The.

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Coding (Platform) · Medium · 55 min

Order History Pages

Workspace: react Difficulty: Medium Time: 55 minutes Context An agent pages through checkout orders and searches for a customer’s order. In the supplied React screen, a slow response can.

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Coding (Platform) · Easy · 35 min

Checkout Work Queue

Workspace: react Difficulty: Easy Time: 35 minutes Context Support agents use a checkout work queue to find orders requiring attention. The supplied React screen already renders records and.

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System Design · Medium · 35 min

Design a notification platform that can send email, push, and SMS notifications while respecting user preferences, retries, rate limits, and analytics. Start with a balanced design and call out the highest-risk tradeoff. Scale: 50M users,

Design a notification platform that can send email, push, and SMS notifications while respecting user preferences, retries, rate limits, and analytics. Start with a balanced design and call.

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System Design · Medium · 35 min

Design a feature flag platform for gradual rollouts, kill switches, experiments, and targeted releases across web, mobile, and backend services. Start with a balanced design and call out the highest-risk tradeoff. Scale: 10K flags, 30K

Design a feature flag platform for gradual rollouts, kill switches, experiments, and targeted releases across web, mobile, and backend services. Start with a balanced design and call out the.

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System Design · Medium · 35 min

Design an audit log platform that records security-sensitive actions and lets customers search, export, and retain logs. Start with a balanced design and call out the highest-risk tradeoff. Scale: 500M events per month, customer-specific

Design an audit log platform that records security-sensitive actions and lets customers search, export, and retain logs. Start with a balanced design and call out the highest-risk tradeoff..

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System Design · Medium · 35 min

Design a collaborative comments system for documents with mentions, permissions, unread state, edit history, and real-time updates. Start with a balanced design and call out the highest-risk tradeoff. Scale: 5M documents, 100K concurrent

Design a collaborative comments system for documents with mentions, permissions, unread state, edit history, and real-time updates. Start with a balanced design and call out the highest-risk.

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System Design · Hard · 45 min

Design an alerting and escalation system that routes production incidents to the right on-call engineers while reducing alert fatigue. Start with a balanced design and call out the highest-risk tradeoff. Scale: 2M metric streams, 20K alert

Design an alerting and escalation system that routes production incidents to the right on-call engineers while reducing alert fatigue. Start with a balanced design and call out the.

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System Design · Hard · 45 min

Design a permissions platform for a multi-tenant SaaS product with roles, groups, resource-level access, audit logs, and safe policy changes. Start with a balanced design and call out the highest-risk tradeoff. Scale: 100K tenants, 50M

Design a permissions platform for a multi-tenant SaaS product with roles, groups, resource-level access, audit logs, and safe policy changes. Start with a balanced design and call out the.

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System Design · Hard · 45 min

Design the frontend architecture for a collaborative document editor with offline edits, comments, presence, permissions, and conflict resolution. Start with a balanced design and call out the highest-risk tradeoff. Scale: 100K daily

Design the frontend architecture for a collaborative document editor with offline edits, comments, presence, permissions, and conflict resolution. Start with a balanced design and call out.

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