Screen Ruby candidates on real starter repos

Ruby

Standard~3h

Your team maintains an internal alert triage service. Each incoming alert carries five severity tags — tokens composed of a level indicator and a category code (e.g. 4S 5H 7C 8D JC). The ranking rules for these tag sets follow standard poker hand rankings.

Ruby

Advanced~4h

An online retailer sells five distinct product SKUs. Each item costs $8 at full price. To encourage bundle purchases, the retailer offers tiered discounts when a customer buys distinct items together:

Ruby

Standard~2h

You are building a decoder for a legacy industrial robot controller. The controller receives a continuous stream of 3-character instruction codes. Each triplet maps to a named operation. When a HALT code is encountered, execution stops immediately.

Ruby

Starter~2h

You are cleaning imported contact records before they are saved into a CRM. Each record includes a freeform phone field entered by a human, so the data can contain spaces, dots, parentheses, hyphens, and an optional leading country code of 1.

Ruby

Starter~2h

Classify a delivery drop-off location into the correct fee tier based on its distance from the warehouse.

Ruby

Starter~2h

Calculate the date of scheduled deployment windows. Teams often schedule recurring deployment windows on the same day of the week each month. In this exercise, you will take a description of a deployment window date and return the actual date it falls on.

Ruby

Starter~2h

A maritime signal station transmits messages using a sequence of signal flags. A numeric transmission code determines which flags to raise and in what order.

Ruby

Starter~2h

Implement a HailstoneCascade.steps method that computes how many cascade steps a hailstone particle takes to reach unit mass.

Ruby

Standard~3h

An internal post-mortem tool reconstructs incident chains. Each step in the chain describes an event and how it caused the next, building a cumulative narrative from the root cause forward.

Ruby

Starter~2h

Compile a standings table from match results for a small sports league. Given a list of match results, produce a formatted standings table. Each result line contains two team names and an outcome, separated by semicolons:

Ruby

Advanced~4h

Read the digits shown on an industrial meter's segment display. Each digit is rendered as a 3-column x 4-row pattern of pipes (|), underscores (_), and spaces. Parse these patterns and return the corresponding numeric string.

Ruby

Starter~2h

The [parcel reference code verification process](https://en.wikipedia.org/wiki/International_Standard_Book_Number) is used to validate book identification numbers. These normally contain dashes and look like: 3-598-21508-8

Ruby

Starter~2h

Given a layout diagram, determine which plants belong to each tenant in a shared rooftop planter.

Ruby

Standard~3h

Build a priority index that maps individual codes to their priority levels. Your team maintains an internal incident management tool that groups alert codes by priority level.

Ruby

Starter~2h

A product team tracks how quickly a release ages across several cadence tiers. Given an age in seconds, calculate how old that release would be on:

Ruby

Standard~3h

Generate the lyrics of the cumulative incident ballad Restart Ballad. An on-call engineer keeps restarting a larger system to steady the one before it. Build the output algorithmically rather than copying the final text or reading it from a file.

Ruby

Standard~3h

Arrange route segments into a circular path. You're given a collection of bidirectional route segments. Each segment connects two numbered stops — for example, a segment [2, 3] connects stop 2 to stop 3 and can be traversed in either direction.

Ruby

Standard~3h

Given a person's allergy score, determine whether or not they're allergic to a given item, and their full list of allergies. An allergy test produces a single numeric score which contains the information about all the allergies the person has (that they were t…

Ruby

Standard~3h

Add the adjacent hazard counts to a completed Sensor Grid board. Sensor Grid is an operations dashboard that uses numeric hints to show how many hazards are directly adjacent (horizontally, vertically, diagonally) to a square.

Ruby

Standard~3h

Score a service scorecard. Service scorecards use the same scoring rules as the original bowling exercise, but the story is operational instead of a game. Keep track of the score across 10 windows and apply the same spare and strike bonuses.

Ruby

Starter~2h

Your team maintains a mesh-network relay that transmits short text messages across low-bandwidth channels. Before transmission each message is woven — cleaned, arranged into a rectangular frame, then read column-by-column so characters are spread across time s…

Ruby

Starter~2h

A support dashboard turns certain factors into status signals. The rules of status-signals are that if a given number:

Ruby

Standard~3h

A social media post has gone viral. Every minute since it was published, the number of new views doubles compared to the previous minute.

Ruby

Standard~3h

Implement a warehouse rover controller. A fulfillment center uses autonomous rovers to fetch items from shelving aisles. Before deploying a rover to the floor, the control software needs to verify that movement commands produce the expected outcomes.

Ruby

Standard~2h

You are building a patrol planning tool for a network of watchtowers on an 8×8 observation grid.

Ruby

Standard~3h

Implement a wave signal mixer that models two-component signals. In signal processing, a wave can be represented by two components: an in-phase component (real) and a quadrature component (imaginary).