The Paradigm Shift

Puzzles are only part of the job.
Faurus tests the rest.

Real engineering means databases, services, concurrency and containers. Faurus lets you practise all of it, graded automatically.

01 // Typical Coding Sites

The Textbook Way

Solving isolated code snippets and puzzle syntax without real servers or real architecture.

✕ Memorizing array puzzles and inverted trees
✕ Little or no work on real databases
✕ Single-file code, no concurrency
✕ Basic riddles easily solved by AI copy-paste
✕ No containers, APIs or real Linux

02 // The Faurus Standard

Real-World Engineering

What engineering teams actually ask for: building, debugging and testing real systems.

✓ Live SQL schemas & real Redis instances
✓ Real Docker builds and Linux shells
✓ Backend REST APIs & GraphQL services
✓ Linux multithreading & thread concurrency
✓ Deep code debugging & automated test suites
✓ Hands-on data science notebooks

24 engines, one platform

Not just textbook puzzles.
The whole engineering stack.

Most practice sites stop at puzzles. Faurus grades real software: live SQL queries, Redis commands, Linux, concurrency and production-style APIs, across 24 engines. Tap one to try it.

Live SQL Databases

MariaDB, real seeded schemas

Judged on result sets Try it →

Redis In-Memory State

A live Redis keyspace

TTLs, sorted sets, Lua Try it →

Linux & Command Line

A real shell, sandboxed

Files, processes, pipes Try it →

Full-Stack API Backends

Multi-file Node.js projects

Integration test suites Try it →

Algorithm Core

12 languages, hidden tests

Time and memory limits Try it →

Data Science & ML

Python · NumPy · Pandas

Notebook-style grading Try it →

React Frontend

Components and state

Rendered and tested Try it →

MongoDB Documents

A live mongod instance

Aggregation pipelines Try it →

Live SQL Databases

MariaDB, real seeded schemas

Judged on result sets Try it →

Redis In-Memory State

A live Redis keyspace

TTLs, sorted sets, Lua Try it →

Linux & Command Line

A real shell, sandboxed

Files, processes, pipes Try it →

Full-Stack API Backends

Multi-file Node.js projects

Integration test suites Try it →

Algorithm Core

12 languages, hidden tests

Time and memory limits Try it →

Data Science & ML

Python · NumPy · Pandas

Notebook-style grading Try it →

React Frontend

Components and state

Rendered and tested Try it →

MongoDB Documents

A live mongod instance

Aggregation pipelines Try it →

Docker & Containers

Write real Dockerfiles

Built and checked Try it →

Bash & Shell Pipelines

POSIX shell scripting

I/O redirection & traps Try it →

Git Version Control

Real repositories

Branches & merges Try it →

Concurrency

Threads, locks, async

Repeated stress runs Try it →

GraphQL APIs

Schemas and resolvers

Query-level tests Try it →

OOP & Design

Classes and interfaces

Design-level tests Try it →

Regex & Automata

Pattern matching

Edge-case suites Try it →

TypeScript Types

Type-level TypeScript

Checked by tsc Try it →

Docker & Containers

Write real Dockerfiles

Built and checked Try it →

Bash & Shell Pipelines

POSIX shell scripting

I/O redirection & traps Try it →

Git Version Control

Real repositories

Branches & merges Try it →

Concurrency

Threads, locks, async

Repeated stress runs Try it →

GraphQL APIs

Schemas and resolvers

Query-level tests Try it →

OOP & Design

Classes and interfaces

Design-level tests Try it →

Regex & Automata

Pattern matching

Edge-case suites Try it →

TypeScript Types

Type-level TypeScript

Checked by tsc Try it →

Bug Debugging & Triage

Find and fix the bug

Root cause, not guesses Try it →

Test-Driven Dev (TDD)

You write the tests

Tests must kill mutants Try it →

Functional Programming

Pure functions

Immutability & composition Try it →

Read & Modify Code

Change working code

Real codebases Try it →

HTML/CSS & Standards

Pages graded in Chromium

Layout & pixel checks Try it →

API Testing

HTTP APIs

Request & response tests Try it →

AI Code Review

Review AI-written code

Rubric-graded Try it →

Programming Basics

Your first lines of code

Fundamentals, step by step Try it →

Bug Debugging & Triage

Find and fix the bug

Root cause, not guesses Try it →

Test-Driven Dev (TDD)

You write the tests

Tests must kill mutants Try it →

Functional Programming

Pure functions

Immutability & composition Try it →

Read & Modify Code

Change working code

Real codebases Try it →

HTML/CSS & Standards

Pages graded in Chromium

Layout & pixel checks Try it →

API Testing

HTTP APIs

Request & response tests Try it →

AI Code Review

Review AI-written code

Rubric-graded Try it →

Programming Basics

Your first lines of code

Fundamentals, step by step Try it →

24 Sovereign Engines

0 String Matching

cgroups v2 Kernel Sandboxes

< 1ms Sub-Millisecond Telemetry

Runtime Ecosystem

Who is Faurus for?

Built for students and developers,
and the teams who hire them.

★ 01

Systems Builders Kernel & Concurrency

Systems Builders

Build distributed systems, not toy puzzles under strict Linux cgroup limits.

✓

Real limits: Every run gets time and memory limits, like production.

✓

Live Redis & MariaDB: Zero mocks, real network socket mutations and keyspaces.

✓

Stress runs: Concurrency answers run many times to catch flaky results.

✓

Per-test verdicts: See exactly which case failed and why.

★ 02

SDEs & Developers Machine Coding & APIs

SDEs & Full-Stack

Master real machine coding rounds with multi-file architectures & live test suites.

✓

Multi-File Workspaces: Real controllers, services, middleware, and schemas.

✓

Integration tests: Your API is tested with real requests.

✓

Live databases: SQL, MongoDB and Redis, all real.

✓

AI code review: Review AI-written code and catch its bugs.

★ 03

CS Students & Learners Core Theory & Compilers

CS Students & Learners

Bridge textbook OS scheduling, ACID queries, and sockets to runnable microVMs.

✓

12 languages: C, C++, Java, Python, Go, Rust, TypeScript and more.

✓

Instant feedback: Per-test verdicts with time and memory.

✓

Free plan: 503 free problems across all 24 engines, 20 submissions a day.

✓

Zero Trial Timer: Practice whenever you want without artificial countdowns.

★ 04

Universities & Labs Autonomous Lab Exams

Universities & Labs

Save 100+ TA hours per semester with autonomous lab practicals and mid-sems.

✓

100% Autonomous Autograding: Instant edge-case evaluation with zero manual grading.

✓

Data Sovereignty: Student records and code remain strictly on department VPC.

✓

LMS Native Sync: Instant export to Canvas, Moodle, and departmental CSV sheets.

✓

Zero Vendor Lock: Complete institutional ownership over examination infrastructure.

★ 05

Hiring Teams & Contests Anti-Cheat & Burst Queue

Hiring Teams & Contests

Filter out AI prompt copiers. Evaluate candidates on actual production execution.

✓

Burst queue: Built for contests and hiring drives under load.

✓

AST Similarity Radar: Sub-tree code plagiarism detection across entire candidate pools.

✓

Hardware Integrity Lock: Window injection protection, AI overlays killed on launch.

✓

Proof-of-Work Ranking: Objective ranking based on raw system engineering execution.

Multi-Format Evaluation Workbench

Beyond basic DSA.
Every engineering dimension in one canvas.

Real technical evaluation demands more than textbook puzzles. Assess production machine coding, database query optimization, system design RFCs, mathematical bounds, and oral architecture defense.

SANDBOXED

Production Machine Coding

Sandboxed containers, hidden tests & stress runs

EXPLAIN PLAN

Database Internals & SQL

Real MariaDB, MongoDB & Redis, judged on results

FORMULA CHECK

CS Core & Discrete Math

Asymptotic complexity, Mathis throughput & numeric epsilon margins

SEMANTIC RUBRIC

Engineering RFCs & Design

Distributed cache trade-offs, split-brain recovery & design documentation

LIVE AUDIO RUBRIC

AI Voice Defense & Panels

Live oral technical grilling on failure modes, trade-offs & design decisions

COLLABORATIVE

Real-Time Pair Programming

Operational Transformation split-editor with joint terminal execution

Q04 · ALGORITHM Implement High-Throughput LRU Cache with Lock-Free Concurrent Reads

class LRUCache: def __init__(self, capacity: int): self.cap = capacity self.cache = {} # key -> Node self.head, self.tail = Node(0, 0), Node(0, 0) self.head.next = self.tail self.tail.prev = self.head def get(self, key: int) -> int: if key in self.cache: self._promote(self.cache[key]) return self.cache[key].val return -1

✓ 10,000 Concurrent Gets (12ms) ✓ Eviction Order Verified ✓ Memory: 1.4MB [cgroup 256MB] ✓ Clang ASan: 0 Leaks

Q04 · DATABASE Which indexing strategy eliminates temporary tables on range scan `(tenant_id, created_at, status)`?

A. Single B-Tree index on `tenant_id` (Requires Temporary Table)

B. Composite Covering Index `(tenant_id, status, created_at)` [OPTIMAL]

C. Hash index on `(tenant_id, created_at)`

D. Full-text inverted index

✓ EXPLAIN Plan: Using index condition; Using filesort: NO (+4.0 Marks)

Q04 · NETWORKS Calculate effective TCP throughput via Mathis formula: RTT = 40ms, MSS = 1460B, Packet Loss p = 0.001

14.82 Mbps TOLERANCE: ± 0.05 Mbps

Formula check: Mathis equation applied automatically during kernel judge verification.

✓ Exact Match within Tolerable Range ✓ IEEE 754 Floating-Point Precision Verified

Q04 · RFC DESIGN Architecture RFC — Designing Distributed Cache Invalidation with Redis & Kafka

Cache-Aside vs Write-Through Strategy: Dual-write race conditions are mitigated by streaming database binlogs via Debezium CDC into a compacted Kafka topic. Application nodes consume events and evict Redis keys asynchronously with exponential retry backoff.

✓ Semantic Rubric: 9.8/10 (Split-Brain Defense, Consistency, Cold-Start)

Q04 · ORAL DEFENSE Live Oral Architecture Defense — Distributed Deadlock Detection

AI Lead Evaluator: "How do you detect distributed deadlocks across 3 database shards without 2PC lockups?"

Candidate (Audio): "Using Chandy-Misra-Haas edge-chasing algorithm to propagate probe messages along wait-for dependencies..."

✓ Voice Cadence & Technical Precision: 98.4% Confidence

Q04 · PAIRING Collaborative Machine Pairing — Distributed Rate Limiter Implementation

[Collaborative Session Active] Alex (Staff Engineer): "Token bucket handles bursts well, but what happens during Redis cluster reconnects?" Candidate (You): "Fallback to local memory token bucket with conservative rate-limit clamp."

● WebRTC Audio Stream Active · Joint Terminal Execution

Live numbers

Where we are today

Early numbers, straight from our live database.

01 // COMMUNITY LIVE

9,100+

Registered Users

Accounts practising on Faurus.

SOURCE LIVE DATABASE

02 // VERDICTS SANDBOXED

140,000+

Submissions Judged

Each one judged in an isolated sandbox against hidden tests.

JUDGE CLUSTER LIVE FABRIC

03 // CURRICULUM CURATED

1,737+

Live Problems

Problems with hidden test suites, across 24 engines.

DEPLOYMENT CONTINUOUS DEPLOY

04 // RUNTIME ISOLATED

Programming Languages

C, C++, Java, Python, Go, Rust, TypeScript, JavaScript, Ruby, PHP, R and Bash.

ENGINES 24 ENGINES LIVE

Pricing

Start free. Go Pro when you're ready.

One-time passes, no subscription and no auto-debit. You see the full price before you pay.

STARTER FREE FOREVER

Starter FREE

Everything you need to start, in every engine

₹0 / forever

PROBLEMS 503 HAND-PICKED, ACROSS EVERY ENGINE

SUBMISSIONS 20 A DAY (EVERY VERDICT COUNTS)

CONTESTS WATCH CONTESTS & LEADERBOARDS

Start Coding Free No card needed · Sign in with Google or GitHub

PRO PASS EVERYTHING UNLOCKED

Pro Pass PRO

Every problem, unlimited submissions

₹499 ₹399 one-time · ₹399/month

One-time payment · No auto-debit · Renew only if you want

PROBLEMS ALL 1,737, NOTHING LOCKED

SUBMISSIONS UNLIMITED

CONTESTS RATED CONTESTS + POST-CONTEST ANALYSIS

Get Pro Pass You'll sign in first, then pay with UPI, cards or netbanking (Razorpay). Have a coupon? Apply it at checkout.

INSTITUTIONS CAMPUS COHORT

Campus & Labs TEAMS

Universities, placement cells, coaching institutes and hiring teams

Custom / per cohort

ADMIN BATCHES, EXAMS & RESULTS IN YOUR CONTROL

PROCTORING DESKTOP APP & BROWSER EXTENSION

VIVA SCHEDULING + AI-ASSISTED EVALUATION

REPORTS BATCH PROGRESS & WEAK TOPICS

Talk to us Write to the founder: ceo@faurus.app

Clarity & Assurance

Frequently Asked Questions

Straight answers about plans, payments and refunds.

What is the difference between Starter and Pro Pass?

Starter is free forever, no card needed: 503 hand-picked problems across every engine and 20 submissions a day (every verdict counts).

Pro Pass unlocks every problem with unlimited submissions, plus rated contests and the post-contest analysis.

Is Pro Pass a recurring subscription or a 1-time payment?

Pro Pass is strictly a 1-time payment. There are zero auto-debits, zero recurring mandates, and zero hidden renewals. When your 1, 2, 3, or 4-month pass ends, access simply lapses back to the free Starter tier unless you choose to renew manually.

What payment methods can I use?

Payments go through Razorpay: UPI (Google Pay, PhonePe, Paytm, BHIM), debit and credit cards (Visa, Mastercard, RuPay), netbanking and wallets. You sign in to Faurus first, so the pass is tied to your account.

How do the multi-month duration passes work?

Pick 1, 2, 3 or 4 months. Longer passes cost less per month. Pro starts as soon as the payment is confirmed, and buying again while you are Pro adds the new months after your current pass ends.

What is the AI Oral Viva & Architectural Defense?

Top engineering roles demand more than passing unit tests. Faurus features an automated architectural defense panel where you defend your algorithmic complexity, trade-offs, cache invalidation strategies, and failure modes against interactive AI examiner grilling.

Can colleges, universities, or bootcamps deploy Faurus?

Yes. Campus & Labs provides cohort-wide deployments with dedicated administrator dashboards, university LMS integration, automated semester viva evaluation, and student deficit analytics. Email our founder directly at ceo@faurus.app for campus pilots.

What is your refund policy?

Full refund within 7 days of purchase if you have solved fewer than 15 problems and done no AI viva session. Duplicate payments, and Pro that never switched on, are refunded in full. Details in our Refund & Cancellation Policy, or write to ceo@faurus.app.

First line of code to job ready.

Puzzles are only part of the job. Faurus tests the rest.