Go Maps: Semantics Before Internals
Learn when to use Go maps, how keys and zero values behave, why iteration needs care, and how to handle shared state and concurrent updates safely.
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Go Under the Hood · Part 5
Go Maps: Semantics Before Internals
Learn when to use Go maps, how keys and zero values behave, why iteration needs care, and how to handle shared state and concurrent updates safely.
Go Under the Hood · Part 4
Strings, Bytes, and Runes in Go
Compare Go strings, bytes, and runes: when to use each, why UTF-8 boundaries matter, and how validation, mutation, and conversion costs affect real applications.
Go Under the Hood · Part 1
From Go Source to Running Program
Follow Go code from modules and packages through compilation, linking, and runtime startup, with a runnable experiment showing what happens before main.
Go Under the Hood · Part 2
Values, Pointers, and Copies in Go
Understand Go's pass-by-value semantics, pointer aliasing, shallow copies, and ownership through runnable examples that reveal which mutations reach callers.
Go Under the Hood · Part 3
Arrays and Slices Under the Hood in Go
Explore Go arrays and slices through runnable examples of backing arrays, length, capacity, append, copying, and the mutations that shared storage makes possible.
Idempotency: Designing APIs That Survive Retries
Learn why idempotency matters and how to design reliable APIs, database transactions, and event consumers that handle retries without duplicate effects.
AWS Cloud Practitioner Study Notes · Part 67
AWS Cloud Adoption Framework (CAF): Perspectives, Capabilities, and Phases
Detailed AWS Cloud Practitioner study notes explaining AWS CAF perspectives, capabilities, transformation domains, phases, readiness assessment, and exam tips.
AWS Cloud Practitioner Study Notes · Part 65
AWS Cloud Migration Strategies: The 7 Rs Explained
Detailed AWS Cloud Practitioner study notes explaining rehost, replatform, refactor, repurchase, relocate, retain, and retire.
AWS Cloud Practitioner Study Notes · Part 63
Amazon Bedrock vs Amazon Lex: Which Conversational AI Service?
AWS Cloud Practitioner study notes comparing Amazon Bedrock and Lex for generative AI, intents, slots, workflows, tool use, chatbots, and voice apps.
AWS Cloud Practitioner Study Notes · Part 62
AWS AI Services: Bedrock, SageMaker AI, and Pre-Trained APIs
AWS Cloud Practitioner study notes mapping AWS AI services to generative AI, custom ML, vision, documents, language, speech, search, and recommendations.
AWS Cloud Practitioner Study Notes · Part 50
How Amazon CloudWatch Works with Other AWS Services
AWS Cloud Practitioner study notes explaining CloudWatch integrations with EC2, Lambda, RDS, ALB, S3, CloudTrail, VPC Flow Logs, SNS, Auto Scaling, and EventBridge.
AWS Cloud Practitioner Study Notes · Part 52
AWS Config: Configuration History, Rules, and Compliance
AWS Cloud Practitioner study notes explaining AWS Config resource recording, configuration history, managed and custom rules, remediation, and CloudTrail comparisons.
AWS Cloud Practitioner Study Notes · Part 56
Amazon Cognito: User Pools, Identity Pools, and JWT Authentication
AWS Cloud Practitioner study notes explaining Amazon Cognito User Pools, Identity Pools, JWTs, federation, guest access, IAM roles, and API authorisation.
AWS Cloud Practitioner Study Notes · Part 66
AWS Disaster Recovery Strategies: RTO, RPO, and the Four Recovery Patterns
Detailed AWS Cloud Practitioner study notes explaining RTO, RPO, backup and restore, pilot light, warm standby, and active-active DR.
AWS Cloud Practitioner Study Notes · Part 53
Amazon EventBridge: Events, Rules, Event Buses, and Targets
AWS Cloud Practitioner study notes explaining Amazon EventBridge event routing, rules, custom events, schedules, Pipes, targets, and SNS/SQS comparisons.
AWS Cloud Practitioner Study Notes · Part 61
Amazon GuardDuty: Managed Threat Detection for AWS
AWS Cloud Practitioner study notes explaining GuardDuty data sources, threat findings, malware protection, EventBridge automation, and security-service comparisons.
AWS Cloud Practitioner Study Notes · Part 55
AWS IAM Policies: JSON Elements, Permissions, and Evaluation
AWS Cloud Practitioner study notes explaining IAM policy JSON, Allow and Deny, Actions, Resources, Conditions, policy types, and least privilege.
AWS Cloud Practitioner Study Notes · Part 60
Amazon Inspector: Continuous Vulnerability Scanning for AWS Workloads
AWS Cloud Practitioner study notes explaining Amazon Inspector scanning for EC2, ECR, and Lambda, findings, CVEs, network exposure, and remediation.
AWS Cloud Practitioner Study Notes · Part 57
AWS KMS: Encryption Keys, Envelope Encryption, and Key Policies
AWS Cloud Practitioner study notes explaining AWS KMS keys, envelope encryption, key policies, grants, rotation, key types, and service integrations.
AWS Cloud Practitioner Study Notes · Part 64
AWS Network ACLs vs Security Groups: Scope, State, and Multi-AZ Design
AWS Cloud Practitioner study notes explaining how Network ACLs and Security Groups apply across subnets and Availability Zones.
AWS Cloud Practitioner Study Notes · Part 54
AWS Organizations: Multi-Account Governance, OUs, and SCPs
AWS Cloud Practitioner study notes explaining AWS Organizations, management and member accounts, OUs, SCP guardrails, consolidated billing, and account governance.
AWS Cloud Practitioner Study Notes · Part 58
AWS Secrets Manager: Secure Storage, Retrieval, and Rotation
AWS Cloud Practitioner study notes explaining Secrets Manager, secret versions, automatic rotation, KMS encryption, IAM access, and Parameter Store comparisons.
AWS Cloud Practitioner Study Notes · Part 59
AWS Shield: Standard, Advanced, and DDoS Protection
AWS Cloud Practitioner study notes explaining AWS Shield Standard and Advanced, DDoS layers, protected resources, Shield Response Team, and WAF.
AWS Cloud Practitioner Study Notes · Part 51
AWS Systems Manager (SSM): Session Manager, Run Command, and Automation
AWS Cloud Practitioner study notes explaining AWS Systems Manager, SSM Agent, private access, Session Manager, Run Command, Patch Manager, Parameter Store, and State Manager.
AWS Cloud Practitioner Study Notes · Part 37
AWS Cloud Financial Management: Cost Explorer, Budgets, and Optimization
AWS Cloud Practitioner study notes mapping Pricing Calculator, Cost Explorer, Budgets, anomaly detection, CUR, tags, Compute Optimizer, and billing.
AWS Cloud Practitioner Study Notes · Part 47
Amazon CloudWatch Hard and Soft Limits
AWS Cloud Practitioner study notes explaining CloudWatch adjustable quotas, hard limits, alarm actions, metrics, dashboards, and CloudWatch Logs filters.
AWS Cloud Practitioner Study Notes · Part 29
AWS Database Deployments and Management: EC2, RDS, Aurora, and Replicas
AWS Cloud Practitioner study notes comparing self-managed databases, Amazon RDS, Aurora, Multi-AZ deployments, read replicas, backups, and scaling.
AWS Cloud Practitioner Study Notes · Part 48
AWS ABAC: Attribute-Based Access Control with IAM Tags
AWS Cloud Practitioner study notes explaining ABAC, principal and resource tags, IAM condition keys, matching policies, session tags, and RBAC trade-offs.
AWS Cloud Practitioner Study Notes · Part 35
AWS CloudFormation: Templates, Stacks, Rollbacks, and Change Safety
AWS Cloud Practitioner study notes explaining CloudFormation templates, stacks, parameters, outputs, policies, StackSets, drift, and change sets.
AWS Cloud Practitioner Study Notes · Part 31
AWS Database Backups: Automated Backups, Snapshots, and PITR
AWS Cloud Practitioner study notes explaining RDS backups, manual snapshots, point-in-time recovery, DynamoDB PITR, Redshift, and EC2 databases.
AWS Cloud Practitioner Study Notes · Part 30
AWS Database Services: Categories and Use Cases
AWS Cloud Practitioner study notes comparing relational, key-value, document, cache, graph, time-series, wide-column, and warehouse databases.
AWS Cloud Practitioner Study Notes · Part 42
Amazon EC2 Instance Lifecycle: Reboot, Stop, Hibernate, and Terminate
AWS Cloud Practitioner study notes explaining EC2 lifecycle states, billing, IP address changes, EBS persistence, hibernation, and termination behavior.
AWS Cloud Practitioner Study Notes · Part 44
Amazon DynamoDB Attribute Types: Scalar, Document, and Set
AWS Cloud Practitioner study notes explaining all 10 DynamoDB attribute types, API descriptors, lists versus sets, maps, and common data-modeling traps.
AWS Cloud Practitioner Study Notes · Part 33
EC2 Scaling: Vertical, Horizontal, and Auto Scaling Groups
AWS Cloud Practitioner study notes explaining EC2 scale up, scale out, Auto Scaling Groups, launch templates, policies, health checks, and load balancers.
AWS Cloud Practitioner Study Notes · Part 41
AWS EC2 Instance Metadata Service and Important IP Addresses
AWS Cloud Practitioner study notes explaining 169.254.169.254, EC2 metadata, IAM role credentials, user data, and IMDSv1 versus IMDSv2.
AWS Cloud Practitioner Study Notes · Part 40
AWS Global, Regional, and Zonal Services Explained
AWS Cloud Practitioner study notes explaining global, Regional, and zonal service scope, common examples, mixed-scope exceptions, and exam traps.
AWS Cloud Practitioner Study Notes · Part 49
AWS Health Dashboard: Public Events, Account Health, and Alerts
AWS Cloud Practitioner study notes comparing AWS Health public and account-specific events, EventBridge alerts, APIs, CloudWatch, and CloudTrail.
AWS Cloud Practitioner Study Notes · Part 43
Complete Amazon EC2 Launch Timeline: From Pending to Application Ready
AWS Cloud Practitioner study notes explaining the EC2 launch sequence, operating-system boot, cloud-init, user data, services, status checks, and traffic readiness.
AWS Cloud Practitioner Study Notes · Part 45
Interface and Gateway VPC Endpoints Explained
AWS Cloud Practitioner study notes comparing Interface and Gateway VPC endpoints, AWS PrivateLink, S3 and DynamoDB access, NAT, and VPN CloudHub.
AWS Cloud Practitioner Study Notes · Part 34
AWS Load Balancer Types: ALB, NLB, GWLB, and CLB
AWS Cloud Practitioner study notes comparing Application, Network, Gateway, and Classic Load Balancers by layer, protocol, routing, and use case.
AWS Cloud Practitioner Study Notes · Part 28
AWS Networking Services: The Cloud Practitioner Mind Map
AWS Cloud Practitioner study notes mapping VPCs, subnets, routing, gateways, connectivity, and network security services to their core use cases.
AWS Cloud Practitioner Study Notes · Part 32
Amazon RDS Deployment Options: Single-AZ, Multi-AZ, and Read Replicas
AWS Cloud Practitioner study notes comparing Single-AZ, standard Multi-AZ, Multi-AZ DB clusters, read replicas, failover, and read scaling.
AWS Cloud Practitioner Study Notes · Part 26
AWS Security Groups vs Network ACLs: Stateful and Stateless Firewalls
AWS Cloud Practitioner study notes comparing security groups and NACLs by scope, state, rule evaluation, allow/deny behaviour, and troubleshooting.
AWS Cloud Practitioner Study Notes · Part 38
AWS Support Plans: Basic, Developer, Business, and Enterprise
AWS Cloud Practitioner study notes comparing AWS Support plans, response targets, Trusted Advisor access, and the Enterprise On-Ramp transition.
AWS Cloud Practitioner Study Notes · Part 46
AWS Tag Restrictions: Limits, Keys, Values, and Reserved Prefixes
AWS Cloud Practitioner study notes covering tag limits, key and value lengths, allowed characters, case sensitivity, empty values, and the aws: prefix.
AWS Cloud Practitioner Study Notes · Part 36
AWS TCO and Cost Tools: Pricing Calculator and Migration Evaluator
AWS Cloud Practitioner study notes explaining Total Cost of Ownership, CapEx and OpEx, AWS Pricing Calculator, and Migration Evaluator.
AWS Cloud Practitioner Study Notes · Part 39
AWS Support Plan Severity Levels and Response Times
AWS Cloud Practitioner study notes explaining support severity levels, first-response targets, incident actions, and current AWS Support plan changes.
AWS Cloud Practitioner Study Notes · Part 27
VPC Endpoints: Private Access to AWS Services
AWS Cloud Practitioner study notes explaining VPC endpoints, gateway and interface endpoints, PrivateLink, endpoint policies, DNS, and cost considerations.
AWS Cloud Practitioner Study Notes · Part 24
Amazon VPC: AWS Virtual Networks, Subnets, and Connectivity
AWS Cloud Practitioner study notes explaining Amazon VPCs, CIDR blocks, subnets, routing, gateways, NAT, security groups, NACLs, and high availability.
AWS Cloud Practitioner Study Notes · Part 22
CIDR Blocks in AWS: VPC Design, Planning, and Security Rules
AWS Cloud Practitioner study notes explaining CIDR prefixes, VPC design, subnet planning, address counts, /32 rules, and 0.0.0.0/0.
AWS Cloud Practitioner Study Notes · Part 15
Amazon EBS Volume Types: Choosing the Right SSD or HDD
AWS Cloud Practitioner study notes comparing EBS gp3, io2, st1, and sc1 volumes by IOPS, throughput, workload, and cost.
AWS Cloud Practitioner Study Notes · Part 16
Amazon EC2 Instance Families and Lifecycle States
AWS Cloud Practitioner study notes explaining EC2 instance families, naming, workload selection, lifecycle states, and instance billing.
AWS Cloud Practitioner Study Notes · Part 17
Amazon EC2 Security Groups: Stateful Instance Firewalls
AWS Cloud Practitioner study notes explaining EC2 security-group rules, stateful traffic, defaults, group references, ports, and NACL differences.
AWS Cloud Practitioner Study Notes · Part 21
IP Addressing in AWS: IPv4, IPv6, Public, Private, and CIDR
AWS Cloud Practitioner study notes covering IPv4, IPv6, public and private IPs, Elastic IPs, CIDR ranges, subnet limits, and usable addresses.
AWS Cloud Practitioner Study Notes · Part 23
IPv4 Subnetting: Binary, CIDR, and AWS Subnet Design
AWS Cloud Practitioner study notes explaining IPv4 subnetting, host bits, subnet masks, magic numbers, address ranges, and AWS usable IPs.
AWS Cloud Practitioner Study Notes · Part 14
Moving Large Amounts of Data into Amazon S3
AWS Cloud Practitioner study notes comparing S3 uploads, DataSync, Snowball Edge, Snowmobile, and Direct Connect for data migration.
AWS Cloud Practitioner Study Notes · Part 18
AWS Network Components: VPC, Subnets, Routing, and Security
AWS Cloud Practitioner study notes explaining Regions, VPCs, subnets, route tables, gateways, firewalls, endpoints, and VPC connectivity.
AWS Cloud Practitioner Study Notes · Part 25
AWS Network Gateways: Internet, NAT, VPN, Transit, and IPv6
AWS Cloud Practitioner study notes comparing Internet Gateway, NAT Gateway, Virtual Private Gateway, Transit Gateway, and egress-only gateways.
AWS Cloud Practitioner Study Notes · Part 20
Network Types: PAN, LAN, WLAN, CAN, MAN, and WAN
AWS Cloud Practitioner study notes comparing network types by scope, ownership, latency, and their relationship to VPCs and global connectivity.
AWS Cloud Practitioner Study Notes · Part 19
The OSI Model: A Practical Guide for Cloud Networking
AWS Cloud Practitioner study notes mapping the seven OSI layers to TCP, IP, ports, VPC networking, and common AWS services.
AWS Cloud Practitioner Study Notes · Part 11
Amazon S3 Storage: Objects, Buckets, and Storage Classes
AWS Cloud Practitioner study notes on Amazon S3 object storage, buckets, keys, durability, security, versioning, lifecycle rules, and events.
AWS Cloud Practitioner Study Notes · Part 9
AWS Cost and Billing: Pricing, Budgets, and Cost Management
AWS Cloud Practitioner study notes on AWS pricing principles, Free Tier, billing tools, budgets, cost reports, tags, and consolidated billing.
AWS Cloud Practitioner Study Notes · Part 10
AWS Cloud9 and Amazon Q Developer: Cloud IDE vs AI Assistant
AWS Cloud Practitioner study notes comparing AWS Cloud9 with Amazon CodeWhisperer, now part of Amazon Q Developer, and their developer use cases.
AWS Cloud Practitioner Study Notes · Part 5
Six Benefits of AWS Global Infrastructure
AWS Cloud Practitioner study notes on high availability, fault tolerance, low latency, global reach, disaster recovery, and data residency.
AWS Cloud Practitioner Study Notes · Part 4
AWS Global Infrastructure: Regions, Zones, and Edge Locations
AWS Cloud Practitioner study notes on Regions, Availability Zones, CloudFront edge locations, Local Zones, Wavelength Zones, and Direct Connect.
AWS Cloud Practitioner Study Notes · Part 12
Object vs Block vs File Storage in AWS
AWS Cloud Practitioner study notes comparing Amazon S3, EBS, EFS, and FSx by access method, sharing model, performance, and use case.
AWS Cloud Practitioner Study Notes · Part 13
Amazon S3 Storage Classes: How to Choose the Right Tier
AWS Cloud Practitioner study notes comparing S3 storage classes by access frequency, retrieval speed, resilience, and lifecycle cost.
AWS Cloud Practitioner Study Notes · Part 6
AWS Shared Responsibility Model: What AWS and Customers Secure
AWS Cloud Practitioner study notes explaining security of the cloud, security in the cloud, and how responsibility changes across EC2, RDS, S3, and Lambda.
AWS Cloud Practitioner Study Notes · Part 7
AWS Well-Architected Framework: The Six Pillars
AWS Cloud Practitioner study notes covering the six Well-Architected pillars, their goals, key AWS services, and common exam clues.
AWS Cloud Practitioner Study Notes · Part 8
AWS Well-Architected Tool: Review Workloads and Track Risks
AWS Cloud Practitioner study notes on using the Well-Architected Tool to review workloads, identify risks, generate reports, and track improvements.
AWS Cloud Practitioner Study Notes · Part 3
Cloud Computing Models and Deployment Strategies
AWS Cloud Practitioner study notes comparing IaaS, PaaS, SaaS, public cloud, hybrid, on-premises, and multi-cloud deployments.
AWS Cloud Practitioner Study Notes · Part 2
Six Advantages of Cloud Computing
AWS Cloud Practitioner study notes covering the six advantages of cloud computing, from variable costs and elasticity to global deployment.
AWS Cloud Practitioner Study Notes · Part 1
Choosing an AWS Pricing Model by Workload Behaviour
AWS Cloud Practitioner study notes on On-Demand, Savings Plans, Reserved Instances, Spot, Dedicated Hosts, and Capacity Reservations.
Designing Go Services That Fail Gracefully
A practical framework for timeouts, retries, idempotency, and observability in production Go services.
Choosing Boundaries in Event-Driven Systems
How to decide what should become an event, where ownership belongs, and how to avoid accidental coupling.
Terraform Beyond the First Environment
A practical structure for modules, state, review, and safe infrastructure changes as a team grows.
A Measurement-First Performance Investigation
A repeatable method for finding backend bottlenecks without optimising the wrong part of the system.
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