BlankRepo
Practice the senior backend interview loop that actually matters now
Start from a vague backend prompt, build runnable C# code, and see how you perform on the signals senior interviews actually test.
Design the core classes and interfaces for a Cart and Pricing System.
The system must handle:
- • item customizations
- • surge pricing
- • percentage and flat discounts
- • BOGO promotions
- • membership benefits
Signal Map Preview
Blank editor. Real business logic. Requirement pivots when your design is already in motion.
How it works
A practice loop built for how senior backend interviews actually unfold
BlankRepo is designed for the rounds that start with a vague business prompt, force you to make assumptions in real time, and judge whether your code and design still hold when the requirements shift.
01
Read the prompt
Start from a vague backend scenario instead of a polished algorithm problem with a predefined method signature.
02
Clarify requirements
Surface assumptions early and decide what matters before you code yourself into a corner.
03
Write runnable code
Model the domain, create sample flows, and get to working C# code that actually runs end to end.
04
Handle pivots
Adapt when the problem changes mid-round and see whether your design bends or breaks.
05
Review the Signal Map
Get feedback on requirement discovery, executable modeling, and adaptability under pressure.
Example scenarios
Practice the kinds of backend problems that don’t look like LeetCode
Each scenario starts from a vague business prompt and expects you to model the domain, write runnable code, and make progress under changing requirements.
Scenario 01
Delivery Payout Engine
Calculate partner payouts from a stream of order events, then adapt when the same order can appear multiple times and only the latest state should count.
What this tests
Event modeling, status handling, money math, and whether your design survives stream-style updates.
Scenario 02
Cart & Pricing API
Start from a blank editor and design a cart system with customizations, discounts, surge pricing, and merchant-specific promo rules.
What this tests
Domain modeling, price composition, scope control, and how quickly you can get to a runnable first slice.
Scenario 03
Rate Limiter / Quota Service
Build a quota engine that can enforce policy rules for different users and endpoints, then evolve it when exception paths and new limits appear.
What this tests
Policy modeling, extensibility, edge-case thinking, and whether your logic collapses once rules stop being uniform.
The Signal Map
Feedback on the engineering signals that generic coding prep misses
BlankRepo does not just tell you whether your code compiles. It highlights where your approach is strong, where it is brittle, and which parts of your interview process would help or hurt you in a real senior backend loop.
Why it matters
A senior-level loop is rarely just about correctness. It is also about requirement discovery, scope control, design adaptability, and how quickly you can reach a runnable first slice.
What you get
A structured report that shows what you clarified, what you modeled well, where your design bent under pressure, and what to improve before the real interview.
Staff-Level Signal Map
Requirement Clarification
Did you surface the missing assumptions before you started coding, or did you guess and hardcode your way forward?
Executable Modeling
Did you turn the prompt into sensible entities, runnable flows, and code that actually demonstrated the behavior being discussed?
Adaptability Under Pivot
When the requirements changed, did your architecture absorb the shift cleanly, or did the solution start collapsing into special-case logic?
Not just correctness. A clearer read on how you think, scope, model, and adapt.
Who this is for
Built for engineers preparing for harder backend interview loops
BlankRepo is designed for candidates who are being evaluated on vague prompts, runnable code, business logic, and design adaptability — not just isolated algorithm recall.
Primary fit
Senior and staff backend candidates
Especially useful if your interview loops involve blank-editor coding rounds, domain modeling, pricing logic, stateful flows, or hybrid coding-plus-design discussions.
Strong secondary fit
Ambitious mid-level engineers
If you are preparing for more demanding backend interviews than standard LeetCode-style prep covers, this is the kind of practice environment that helps close that gap.
Best used when
You need realistic repetition
Use BlankRepo when you want to rehearse the transition from vague prompt to working code, pressure-test your assumptions, and see whether your design survives requirement changes.
Not the focus
Generic entry-level interview prep
This is not meant to replace foundational algorithm practice. It is built for candidates who need a better way to practice the more open-ended backend interview formats showing up later in the hiring ladder.
Early access
Get early access when the first BlankRepo sessions go live
We’re building the practice environment we wish existed for modern backend interview loops. Join the waitlist to get early product updates, beta access, and new scenario releases.
• Early beta invites
• New scenario drops
• Sample Signal Maps
• Zero spam, only product updates
Join the waitlist
No payment. No commitment. Just a heads-up when BlankRepo is ready to try.