Digital Garden

Go has no built-in enum keyword. The idiomatic alternative is a typed constant group combined with iota — a compile-time counter that auto-increments within a const block. The result behaves like an e

Go Generics

Generics (introduced in Go 1.18) let you write functions and types that work across multiple types without duplicating code. The key idea: type parameters — placeholders for concrete types supplied at

Go Proverbs

A collection of wise, pithy design principles from Rob Pike — one of Go's creators. Presented at Gopherfest 2015, they capture the philosophy behind idiomatic Go. Similar in spirit to the Zen of Pytho

Go HTTP Clients

Go's standard library ships a production-ready HTTP client in net/http — no third-party dependency needed. This note covers the full lifecycle: making requests, working with JSON, understanding URLs a

Go Mutexes

A mutex (mutual exclusion lock) protects shared data from concurrent access. While channels communicate data between goroutines, a mutex guards data that multiple goroutines read or write directly. Fr

AWS Lambda

- Serverless compute — run code without provisioning or managing servers - Event-driven — executes in response to triggers (S3, API Gateway, Kinesis, DynamoDB Streams, SNS, SQS, etc.) - FaaS (Function

Go Channels & Goroutines

Go's concurrency model is built on two primitives: goroutines (lightweight threads managed by the Go runtime) and channels (typed, thread-safe pipes for goroutines to communicate through). The philoso

Go Control Flow

Go's control flow for conditionals is intentionally minimal: if/else for branching and switch as a cleaner alternative to long if-else chains. No parentheses around conditions, braces always required.

Go Error Handling

Go handles errors as values, not exceptions. There's no try/catch — instead, functions return an error as the last return value, and callers check it explicitly. This makes error paths visible, forces

Go Functions

Functions are first-class citizens in Go — they can be assigned to variables, passed as arguments, and returned from other functions. Types come after variable names. Go natively supports multiple ret

Go Quiz & Coding Challenges

How to use: Go section by section. For "What's the output?" — reason through it before expanding. For coding challenges — write the solution first, then verify. --- go package main import "fmt" var x

Go Interfaces

An interface defines a set of method signatures. Any type that implements all those methods automatically satisfies the interface — no explicit implements declaration needed. This is called structural

Go Loops

Go has exactly one looping construct: for. It replaces C's for, while, and do-while. No parentheses around the loop header, braces always required. This keeps the language minimal without sacrificing

Go Maps

A map is Go's built-in hash map — an unordered collection of key-value pairs with O(1) average lookup, insert, and delete. Keys must be a comparable type (anything you can use == on). Maps are referen

Go Packages & Modules

Go code is organized into packages (a directory of .go files that share a package declaration) and modules (a collection of related packages defined by a go.mod file). Every file belongs to a package.

Go Pointers

A pointer holds the memory address of a value rather than the value itself. Pointers let you share and mutate data across function boundaries without copying it. Go pointers are simpler than C pointer

Go Slices

A slice is Go's dynamically-sized, flexible view into an array. Unlike arrays (fixed size, part of the type), slices can grow and shrink. They are the standard way to work with ordered collections in

Go Structs

A struct is Go's primary way to group related data. It's equivalent to a class without inheritance — you get data fields and methods attached to the type. Go favours composition over inheritance throu

Go Variables & Types

Go is statically typed — every variable has a type fixed at compile time. The compiler catches type mismatches before the program runs. Types are written after the variable name (opposite to C/Java).

AWS VPC

2026-04-03

--- - Virtual Private Cloud — your own isolated private network within AWS - Spans all AZs in a region (regional resource) - You control: IP ranges, subnets, route tables, gateways, security rules - A

AWS ML Associate Exam — Index & Guide

Comprehensive exam notes. Each domain has a dedicated file. --- ------ Exam Code MLA-C01 Duration 170 minutes Questions 65 questions (multiple choice + multiple response) Passing Score 7

Domain 1 — Data Preparation for ML (28%)

Largest domain. Focus on: S3, Glue, Athena, Kinesis, SageMaker Ground Truth, Feature Store, and feature engineering techniques. --- mermaid graph LR Raw[Raw Data] -- S3[S3<br/Data Lake] S3 --

Domain 2 — ML Model Development (26%)

Focus: SageMaker training jobs, built-in algorithms, custom containers, hyperparameter tuning, and SageMaker JumpStart. --- mermaid graph TD Studio[SageMaker Studio<br/Web IDE] -- NB[Notebooks]

Domain 3 — Deployment & Orchestration of ML Workflows (22%)

Focus: SageMaker endpoint types, inference patterns, SageMaker Pipelines, CI/CD for ML, and MLOps best practices. --- mermaid graph TD Inference[Inference Options] -- RT[Real-time Endpoint<br/Low

Domain 4 — Monitoring, Maintenance & Security (24%)

Focus: SageMaker Model Monitor, Clarify, drift detection, retraining triggers, IAM, VPC, encryption, and cost optimisation. --- mermaid graph LR Deploy[Model Deployed] -- DriftD[Data Drift<br/Inpu

ML Fundamentals — AWS ML Associate

Core ML concepts tested across all domains of MLA-C01. --- mermaid graph TD ML[Machine Learning] -- SL[Supervised Learning<br/Labeled data] ML -- UL[Unsupervised Learning<br/No labels] ML

AWS AI Services & Bedrock — AWS ML Associate

Pre-built AI APIs — no ML expertise needed. Use when you don't want to build/train your own model. --- mermaid graph TD AI[AWS AI Services] -- Vision[Computer Vision] AI -- NLP[Natural Languag