LearnGoNotificationApp

A Go project I'm building as I learn the language — applied to a real-world notification system architecture.

Rather than following a tutorial, I'm using Go concepts as I learn them to build something that reflects real-world patterns. Each new concept gets applied directly to this project rather than living in a throwaway exercise file.

What it does

Models a customer outreach notification system where recipients receive reminders or blast notifications through different channels (SMS, email). The system tracks outreach status per recipient and handles failures gracefully.

Architecture

LearnGoNotificationApp/
    main.go              — orchestration, main loop, result categorization
    go.mod
    enums/
        outreachStatus.go  — typed OutreachStatus enum (NotSent, Failed, Success)
        outreachType.go    — typed OutreachType enum (Reminder, Blast)
    models/
        notificationSender.go — NotificationSender interface
        person.go          — Person struct with status tracking
    senders/
        emailSender.go     — Email implementation
        smsSender.go       — SMS implementation
    utils/
        maputils.go        — generic FilterMap utility for map filtering
    workers/
        notificationWorker.go — worker pool, processes notifications from channel

Concepts applied so far

• Package organization — models, senders, enums as separate packages
• Interface-driven architecture — pluggable sender implementations
• Typed enums — OutreachType and OutreachStatus prevent invalid states at compile time
• Error handling — multiple return values, no try/catch
• Structs and methods — Person with constructor and Stringer
• Exported vs unexported identifiers — Go's access control model
• Maps, slices, for range loops — core data structures in practice
• Pointers — why the map stores *Person not Person
• Goroutines + channels + WaitGroups — worker pool pattern for concurrent processing

Learning log

Concept	Applied as
Variables, types, control flow	Notification routing and status checks
Functions + multiple return values	sendReminder returning (bool, error)
Structs + methods	Person model with String() formatter
Interfaces	NotificationSender with SMS and Email implementations
Package organization	models / senders / enums separation
Typed enums	OutreachType replacing raw strings
Goroutines + WaitGroups	Coming next — concurrent notification processing
Generics + higher-order functions	FilterMap utility for filtering notification results
Goroutines + channels + WaitGroups	Worker pool for concurrent notification processing

What's coming

• Tests — table-driven tests for FilterMap, processNotification, and worker behavior
• HTTP integration for real SMS/email providers
• Config file for recipient data instead of hardcoded values
• Additional outreach channels (push notifications)

Why this project

Notification systems are a common real-world pattern — queuing, routing, status tracking, failure handling, pluggable integrations. Building around a familiar architecture means I can focus on learning Go without also figuring out the problem domain from scratch.

Stack

• Go 1.21+
• No external dependencies — standard library only