Port Scanner using Go Programming

Building a port scanner in Go is an excellent way to learn both network programming and Go's powerful concurrency model. Port scanners are fundamental tools in security reconnaissance — understanding which ports are open on a target system is the first step in any security assessment. Go is an ideal language for this task because of its goroutines and channels, which make concurrent network operations both efficient and readable. Basic approach: Create a TCP dial attempt for each port with a short timeout. Use goroutines to scan multiple ports simultaneously. Use a channel to collect results and a WaitGroup to manage goroutine lifecycle. The key security insight is that scanning many ports sequentially is too slow to be practical. By using Go's concurrency primitives, you can scan hundreds of ports simultaneously while keeping memory usage low and code complexity manageable. This kind of hands-on security tooling practice is valuable for AppSec engineers who want to understand attacker techniques and build intuition for how network-level vulnerabilities are discovered and exploited.