Code Review
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10 problems15–30 min eachHints when you're stuck
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LanguageEasy0 of 3 done
Product Listing Endpoint: Search, Sort and Pagination
FreeAn online shop's product listing endpoint that adds search by name, sorting and page-by-page browsing.
Backend15 minRide Booking Service
PremiumA function that validates a trip request, calculates the fare, and books the ride.
Backend20 minOrders Export: Download Orders as a Spreadsheet
PremiumA merchant dashboard that adds a CSV download of the merchant's orders for a chosen date range.
Backend18 minMedium0 of 4 done
Shipping Carrier API Client Library
PremiumA client library merchants install to get shipping rates, buy labels and list shipments, adding retries, token refresh and paging.
Backend22 minAI Ticket Summary Endpoint
PremiumA help-desk endpoint that asks an AI model to summarize a support ticket and suggest its priority.
Backend25 minPassword Reset: Forgot-Password Emails and Setting a New Password
PremiumA sign-in service that adds "Forgot password?": users request a link by email and use it to choose a new password.
Backend25 minUploading Expense Receipts
PremiumAn expenses service that lets employees attach receipt photos and PDFs to their claims, with previews for approvers.
Backend25 minHard0 of 3 done
Hotel Room Holds: API, Payment Webhook and Expiry Worker
PremiumA booking service that holds a room while the guest pays, confirms it from the payment provider's webhook, and releases expired holds in a background job.
hardBackend30 minPayment Events Consumer: Posting to the Ledger
PremiumA service that reads payment events from a stream and posts balanced ledger entries, adding refunds and parallel processing.
hardBackend30 minOrder Book: Price Levels, Market Orders and Cancellations
PremiumAn exchange's matching engine that replaces a simple matcher with a price-level order book, and adds market orders and faster cancels.
hardBackend30 min