Implement a User-Space Shell with Process and Signal Handling
Overview
What this challenge is about.
Build a POSIX shell in C with pipelines, redirection, signals, and built-ins. Submit your code and design note for a verifiable certificate.
The scenario
The startup (terminal-productivity tool used by around 18,000 developers, expanding the systems team from 4 to 8 in 6 months) reads design notes more closely than line-count.
The Brief
What you'll do, and what you'll demonstrate.
Implement a POSIX-style shell in C with pipelines, redirection, background jobs, and proper signal handling against a 25-case test script.
Earning criteria — what you'll demonstrate
- Use fork/exec/wait/pipe/dup2 to implement Unix process semantics
- Handle SIGCHLD and SIGINT correctly without race conditions
- Implement built-ins that must run in the shell process (cd) vs. children (others)
- Write a test script that exercises the tricky cases, not just happy paths
Program Fit
Where this fits in your program.
Sharpens the same skills your degree expects you to demonstrate.
Computer Systems and Organization
Bachelor · Systems
Strong alignment
This challenge maps to Computer Systems and Organization at the Bachelor level. It sharpens the same practical skills your coursework expects — but in a real industry context with actual constraints and deliverables.
Skills
Skills you'll demonstrate.
Each one shows up on your verified credential.
- System Calls
Apply system calls to solve real industry problems and demonstrate production-level capability.
- Process Management
Apply process management to solve real industry problems and demonstrate production-level capability.
- Signal Handling
Apply signal handling to solve real industry problems and demonstrate production-level capability.
- C Programming
Apply c programming to solve real industry problems and demonstrate production-level capability.
- Ipc
Apply ipc to solve real industry problems and demonstrate production-level capability.
- Documentation
Apply documentation to solve real industry problems and demonstrate production-level capability.
Careers
Career paths this challenge builds toward
Completing this challenge demonstrates skills that transfer directly to these roles: