Software Craftsperson

Design a Content Delivery Network (CDN)

Sat, 21 Dec 2024 12:16:28 +0100

Design a highly available CDN from scratch. Learn about edge servers, caching strategies, content propagation, and global content distribution.

Design a Distributed Key-Value Store

Sat, 21 Dec 2024 12:16:28 +0100

Design a highly available key-value store like DynamoDB or Redis. Learn about consistent hashing, replication, partitioning, and handling failures.

Introduction

Mon, 15 Jul 2024 20:30:26 +0100

A look at the concepts you must know if you are using kubernetes to run applications or a software development team that uses kubernetes

Databases Introduction - System Design Fundamentals

Sat, 10 Dec 2022 20:51:37 +0000

What is a database and why do we need it? Learn about database fundamentals, types of databases, SQL vs NoSQL, and when to use each for system design.

Load Balancers Explained - Part 1

Fri, 25 Nov 2022 17:55:38 +0000

What is a load balancer? Learn about global and local load balancing, load balancing algorithms, health checks, and how to scale distributed systems effectively.

System Maintainability - Building Evolvable Systems

Sun, 30 Oct 2022 11:30:09 +0000

What is maintainability in system design? Learn about code quality, documentation, modularity, and building systems that are easy to modify and debug.

Abstractions in System Design - Building Modular Systems

Thu, 27 Oct 2022 20:16:27 +0100

What are abstractions and why are they crucial in system design? Learn how abstraction layers simplify complexity and enable scalable architectures.

What is a System Design Interview

Sun, 16 Oct 2022 12:16:28 +0100

Why do organisations conduct system design interviews? What is expected from the candidate? Learn how to prepare and ace your system design interview.

Architecture

Tue, 16 Jul 2024 05:53:40 +0100

A look at the concepts you must know if you are using kubernetes to run applications or a software development team that uses kubernetes

Databases - NoSQL Fundamentals

Sun, 11 Dec 2022 16:06:32 +0000

Understanding NoSQL databases - when to use them, types of NoSQL databases, and how they differ from relational databases for system design.

Load Balancers Layer 4 vs Layer 7 - Deep Dive

Mon, 05 Dec 2022 21:27:29 +0000

Understanding Layer 4 and Layer 7 load balancers, OSI model, hardware vs software load balancers, and choosing the right load balancing approach.

Fault Tolerance - Designing Resilient Systems

Sun, 30 Oct 2022 13:53:39 +0000

What is fault tolerance in system design? Learn about graceful degradation, redundancy, circuit breakers, and building systems that handle failures.

Consistency Models in Distributed Systems

Thu, 27 Oct 2022 20:56:46 +0100

Understanding consistency models from strong consistency to eventual consistency. Learn CAP theorem, consistency trade-offs, and choosing the right model.

System Design Interview Preparation - Structured Learning Path

Sat, 22 Oct 2022 14:31:27 +0100

How to prepare for system design interviews with a structured approach. Learn the fundamentals, practice case studies, and master interview techniques.

What are Containers

Wed, 17 Jul 2024 21:02:54 +0100

A look at the concepts you must know if you are using kubernetes to run applications or a software development team that uses kubernetes

Database Resiliency - Replication and Disaster Recovery

Fri, 23 Dec 2022 19:43:01 +0000

Learn about database replication strategies, disaster recovery, data redundancy, and ensuring high availability for distributed systems.

System Availability - Understanding Uptime and SLAs

Sun, 30 Oct 2022 08:25:15 +0000

What is availability in system design? Learn how to measure availability, understand SLAs, calculate nines (99.9%, 99.99%), and design highly available systems.

Failure Models in Distributed Systems

Sun, 30 Oct 2022 06:48:26 +0000

Understanding failure modes in distributed systems. Learn about crash failures, Byzantine failures, network partitions, and the fallacies of distributed computing.

What to Do During Your System Design Interview

Tue, 25 Oct 2022 22:48:03 +0100

Ace your system design interview with proven strategies. Learn how to handle stress, ask clarifying questions, communicate effectively, and structure your solution.

Database Scalability - Sharding and Partitioning

Fri, 13 Dec 2024 19:43:01 +0000

Learn database sharding, partitioning strategies, consistent hashing, and how to scale databases horizontally for millions of users.

Nodes

Thu, 18 Jul 2024 22:11:44 +0100

A look at the concepts you must know if you are using kubernetes to run applications or a software development team that uses kubernetes

Approximate Calculations for System Design Interviews

Mon, 31 Oct 2022 21:06:57 +0000

Master back-of-the-envelope calculations for system design. Learn to estimate storage, bandwidth, QPS, and make quick capacity planning decisions.

System Reliability - Building Dependable Systems

Sun, 30 Oct 2022 09:54:06 +0000

What is reliability in system design? Learn how to measure MTBF, MTTR, build fault-tolerant systems, and ensure consistent performance.

What is System Design? Understanding the Fundamentals

Wed, 26 Oct 2022 21:12:54 +0100

What is system design and why does it matter? Learn the core concepts, principles, and thinking patterns behind designing scalable distributed systems.

Objects and manifests - an introduction

Mon, 05 Aug 2024 22:37:12 +0100

A look at the concepts you must know if you are using kubernetes to run applications or a software development team that uses kubernetes

Domain Name System (DNS) Explained

Mon, 21 Nov 2022 20:25:01 +0000

What is DNS and how does it work? Learn about the internet's phonebook, DNS architecture, resource records, and how domain names translate to IP addresses.

System Scalability - Horizontal and Vertical Scaling

Sun, 30 Oct 2022 11:07:16 +0000

What is scalability in system design? Learn horizontal vs vertical scaling, load balancing, caching strategies, and designing systems for millions of users.

The path to become an expert in k8s

Fri, 13 Dec 2024 22:37:12 +0100

Now that you have seen the basics, how do you become a seasoned professional with k8s

What Is an AI Agent? The Loop Behind the Hype

Thu, 08 Oct 2026 00:19:06 +0100

An AI agent is a loop: the model proposes, the harness runs tools and feeds results back. How the loop works, how it ends, and why it has no 'impossible' exit.

1,200 Agents and a Package Cache: What the OpenAI–Hugging Face Incident Teaches Us

Sat, 03 Oct 2026 00:00:00 +0000

How AI agents in an OpenAI evaluation turned a package cache into a message board, breached Hugging Face, and what engineers should learn from it.

Culture Is the Operating System: How Engineering Leaders Build, Scale and Renew Great Teams

Sat, 15 Aug 2026 00:00:00 +0000

Why culture is a team's operating system, and how engineering leaders build, scale and renew it as a company grows from startup to scale-up to maturity.

The Art of Estimation in Software Engineering

Tue, 28 Jul 2026 19:18:32 +0100

A practical guide to software estimation: reduce ambiguity, improve confidence, and choose the right sizing units for initiatives, epics, and stories.

Accomplishment Amnesia: What It Is and How to Overcome It

Sun, 26 Jul 2026 16:08:48 +0100

Learn why high achievers forget their wins, how accomplishment amnesia fuels self-doubt, and practical habits to rebuild confidence and self-respect.

Building High-Agency Software Engineering Teams

Sat, 25 Jul 2026 18:03:41 +0100

A framework for engineering leaders to foster team autonomy, psychological safety, and ownership culture through hiring, enablement, and accountability systems.

From shiny toys to daily workhorse - how we transformed our approach to Generative AI in engineering

Wed, 15 Jul 2026 00:00:00 +0000

How I moved my team's GenAI use from shiny toys to a daily workhorse: no mandates, just a dedicated space for structured experiments, and what we learnt.

Practical GitHub Repository Hardening for a Hugo Site

Wed, 01 Apr 2026 09:00:00 +0100

A practical playbook for hardening a Hugo repository with reproducible builds, dependency controls, secret scanning, Semgrep, scorecards, and local guardrails.

When Your Workplace Controls Your Personal GitHub Repos: Understanding GitHub Org Policies

Wed, 01 Apr 2026 09:00:00 +0100

Joining a GitHub organisation with your personal account can let enterprise policies restrict your private repos. Here's how GitHub's permission layers work.

Prompting Essentials for Software Engineers: 4 Practical Strategies for Better AI Output

Sun, 29 Mar 2026 21:43:23 +0100

Four practical prompting strategies software engineers can use with LLMs to gather better requirements, weigh trade-offs and ship higher-quality code.

Start Here to Learn Large Language Models: Best Andrej Karpathy Resources

Sat, 07 Mar 2026 21:38:10 +0000

Start your LLM learning journey with Andrej Karpathy's best talks on pretraining, finetuning, scaling laws, and practical model-building resources.

From Concept to Production: Building CalOohPay with AI-Assisted Development

Sat, 31 Jan 2026 10:00:00 +0000

How I built CalOohPay, from a CLI tool to a web app, with GitHub Copilot and Claude Sonnet: what AI-assisted coding sped up and why clear constraints mattered.

Shift Reliability Left: Use SLOs to Guide Architecture Early

Thu, 04 Dec 2025 09:00:00 +0000

A practical guide to defining SLOs and SLIs early in the SDLC so reliability requirements shape architecture, testing, and release decisions.

To Code or Not to Code as an Engineering Manager: Making the Right Choice

Thu, 30 Oct 2025 21:44:57 +0100

Should engineering managers code? My take: your EM archetype, what your organisation expects, staying close to your team's workflow, and coding outside work.

Transactional Outbox Pattern: A Practical Guide to Trade-offs

Mon, 08 Sep 2025 21:40:52 +0100

How the Transactional Outbox Pattern solves the dual write problem between your database and message broker, with implementation choices and trade-offs.

The Honey Badger Management Framework

Tue, 29 Jul 2025 10:13:49 +0100

A critical look at the Honey Badger Management Framework: its Guru, Manager and Specialist roles, ESG and AI claims, and how it compares with Scrum.

Moving to AWS Amplify from Azure

Mon, 26 May 2025 08:16:14 +0100

How I moved a Hugo blog from Azure Front Door to AWS Amplify Hosting: the amplify.yml build spec, a Route 53 hosted zone and a zero-downtime DNS switch.

Azure CDN, Front Door and the cost

Fri, 25 Apr 2025 22:41:59 +0100

One click on Azure's prompt to migrate my static blog from Azure CDN to Front Door Standard pushed hosting to £34 a month. What changed and what I did next.

How to install an older version of Hugo on MacOs

Sat, 12 Apr 2025 16:26:05 +0100

Hugo 0.146.0 broke PaperMod builds. Here is how to install an older Hugo binary on macOS in a local bin directory and put it first on your PATH.

Evolving your Leadership Style as you scale your organisation

Sat, 14 Dec 2024 22:58:57 +0530

What worked when leading one small team stops working as you lead many. Why your leadership style has to evolve as your organisation scales, and how mine did.

How and Why should you Sign Git Commits with GPG: A Practical Guide

Thu, 12 Dec 2024 09:00:00 +0000

How and why to sign Git commits with GPG: what commit signing proves, how it prevents identity spoofing, and step-by-step setup for macOS, Linux and GitHub.

Adding a responsive menu to your Hugo PaperMod blog

Sat, 09 Nov 2024 16:37:36 +0000

Add a responsive hamburger menu to a Hugo PaperMod blog by overriding header.html with custom CSS and JavaScript, so mobile readers can navigate easily.

Why your internal developer platform will fail

Thu, 31 Oct 2024 21:35:44 +0000

Why internal developer platforms fail and how to avoid it: lessons from leading a platform engineering team on giving your IDP a product mindset.

Managing life with a new born

Sun, 20 Oct 2024 21:04:16 +0100

What no one tells you about starting a family while working in tech: preparing for the birth, parental leave, returning to work and the daycare sickness wave.

Virtual Private Cloud (VPC): A Practical Guide to Cloud Network Isolation

Wed, 21 Aug 2024 21:44:57 +0100

What a VPC is, how subnets and security layers isolate your network in the public cloud, and a step-by-step example of creating one on AWS from scratch.

The Hidden Dangers of Unconscious Bias: Understanding and Managing Implicit Prejudices

Thu, 15 Aug 2024 07:55:18 +0100

What unconscious bias is, how it quietly shapes our judgements of people, the harm it does to careers and communities, and ways to recognise and manage it.

Lack of product thinking - A rant

Mon, 01 Apr 2024 22:28:49 +0100

A rant on why engineers chase shiny tech over users' real problems: how rewriting a monolith into microservices went wrong, and why product thinking matters.

Using Hugo Modules for themes

Mon, 01 Apr 2024 15:29:34 +0100

Switch your Hugo theme from a Git submodule to a Hugo Module, and fix the 'module not found' error caused by leaving the theme setting in config.yml.

What is Incident Management in Software Engineering?

Sat, 02 Mar 2024 07:09:15 +0000

Incidents, managing them and the various roles involved in managing them. How do you go about setting up an incident management process for your org?

What is my Management Philosophy

Tue, 20 Feb 2024 21:44:40 +0000

My engineering management philosophy: psychological safety, trust, a rigorous hiring process, candid feedback, and helping my reports grow beyond me.

The journey of an email - from sender to receiver and everything in between

Sun, 18 Feb 2024 18:21:06 +0100

Follow an email from sender to inbox: user agents, mail servers, SMTP, POP3 and IMAP, then how SPF, DKIM and DMARC stop spoofing of your domain.

Updating PaperMod to the latest and greatest

Tue, 06 Feb 2024 22:42:57 +0000

Notes from updating the PaperMod theme: why it forced a Hugo upgrade, and swapping an abandoned Hugo GitHub Action for peaceiris/actions-hugo in CI.

How I optimised my blog's search performance

Mon, 05 Feb 2024 00:25:31 +0000

Speed up Hugo PaperMod's Fuse.js search by debouncing the type-ahead and listening to the input event, so search no longer runs on every keystroke.

How to add commenting functionality to your Hugo Blog using Utterances

Sun, 04 Feb 2024 18:36:45 +0000

Add free, open-source comments to a Hugo PaperMod blog with Utterances, which stores each post's discussion as a GitHub issue. Setup takes minutes.

How to create a custom mode for Hugo-PaperMod theme using go template and html

Sat, 03 Feb 2024 22:23:40 +0000

Creating a custom landing page for Hugo-PaperMod that is a combination of the HomeInfo mode and the profile mode. I call it the Hybrid mode.

Style Modifications to Hugo PaperMod

Fri, 02 Feb 2024 04:00:31 +0000

A quick look at hugo-PaperMod-Mod, a set of community CSS tweaks that add thumbnails, a sidebar table of contents and wider posts to Hugo PaperMod.

Hugo Partial for Buy me a coffee button

Tue, 26 Dec 2023 21:43:00 +0000

Learn when to use a Hugo partial template instead of a shortcode, and add a Buy Me a Coffee button to every blog post without editing each post.

What happens during a TLS handshake?

Sun, 22 Oct 2023 14:02:28 +0100

An illustrated, step-by-step walkthrough of the TLS handshake between a client and server over HTTPS using RSA key exchange, drawn for beginners.

Handling conflicts in a high performing team

Sun, 17 Sep 2023 11:04:20 +0000

Why conflict in high-performing teams is healthy, why disagreements turn personal, and how a manager can recognise the problem and coach people to resolve it.

Why and When would you use a Serverless approach to solving your problem?

Sun, 11 Jun 2023 13:02:28 +0100

Serverless versus fully orchestrated solutions: cold starts, testing, lock-in, pay-per-use and built-in scaling, and how I answered it in an interview.

Why I became an Ethnic Diversity Community Lead

Fri, 21 Apr 2023 21:52:28 +0100

Why I volunteered as an Ethnic Diversity Community Lead: facing racism growing up in the UAE, the value of diverse teams, and the challenges ahead.

Switching from managing teams to managing managers

Wed, 15 Feb 2023 13:04:20 +0000

What changes when you move from managing engineers to managing other managers: more thinking than doing, driving outcomes, and leading through others.

What is Homebrew? How is it useful?

Sun, 25 Dec 2022 20:40:00 +0000

What Homebrew is and why every Mac developer installs it, with its vocabulary explained: formulae, bottles, the cellar, kegs, racks and taps.

Setting up your Macbook Pro as a developer

Sun, 25 Dec 2022 18:04:20 +0000

How I set up a new MacBook Pro as a developer, from first boot and Apple ID to the App Store, browser and tools, so setting up the next one takes far less time.

What did I learn from The Unicorn Project?

Sat, 24 Dec 2022 00:16:02 +0000

What I learnt from The Unicorn Project, Gene Kim's follow-up to The Phoenix Project: a summary of the book and its five ideals, from locality to customer focus.

What is a System Design Interview

Sun, 16 Oct 2022 12:16:28 +0100

What a system design interview is, why companies run them and what interviewers expect, with how to prepare and the distributed systems fundamentals to know.

Creating a great organisational culture

Fri, 07 Oct 2022 19:38:31 +0100

Learn how to build a positive organisational culture through clear values, thoughtful hiring, strong leadership, career frameworks, and belonging.

Psychological Safety: What, how and why?

Sat, 13 Aug 2022 13:22:14 +0100

What psychological safety is, why it matters, how it differs from a safety culture, why it matters in software engineering, and the benefits it brings to teams.

Invisible Work and how you can tame it in your organisation

Sun, 07 Aug 2022 16:25:57 +0100

What invisible work is, why it hurts leaders and team members alike, and the true story of how one team made its hidden work visible and got it under control.

What is Self Management and why do you need to get better at it?

Mon, 27 Jun 2022 23:35:31 +0100

What self-management is and why getting better at it makes you a better leader: self-awareness, motivation, social skills, empathy, accountability, influence.

Azure Service Principal Credential Reset

Sat, 23 Apr 2022 17:21:09 +0100

My GitHub Actions deploy failed because an Azure service principal's client secret had expired. How to reset the credential in the Azure portal or with the CLI.

Coaching conversations using the GROW Model

Mon, 18 Apr 2022 16:05:59 +0100

What the GROW coaching model is, how Goal, Reality, Options and Will structure a coaching conversation, and a worked example of using it with a team member.

Leadership, trust and how not to ruin it

Sat, 26 Mar 2022 11:44:58 +0000

A manager's view of trust and leadership in a fast-changing company: respect, favouritism, narcissism, personal boundaries and practising what you preach.

What are Git submodules?

Sat, 19 Feb 2022 20:39:46 +0000

What Git submodules are and how to use them: adding a repository as a submodule, cloning a repo that has submodules, and pulling the submodule's latest version.

What is Agile Scrum?

Mon, 14 Feb 2022 02:13:20 +0000

What is Agile, what is Scrum, and are they the same thing? The Agile values, Scrum's three pillars of empiricism, its values and its three accountabilities.

Building software quality from Day 1 using Lean Quality Assurance

Sun, 30 Jan 2022 16:24:06 +0000

How to build quality in from day one with lean QA: teams owning quality, cutting waste in testing, finding bugs sooner and getting everyone doing agile testing.

Customize your Mac or Linux prompt or terminal

Sun, 23 Jan 2022 10:10:13 -0800

How I customised my terminal prompt on macOS and Linux to show the current git branch and more, coming back to the command line as an engineering manager.

Site Reliability Engineering vs DevOps — How they differ and when to use each

Sat, 04 Dec 2021 00:17:06 +0000

A practical comparison of Site Reliability Engineering (SRE) and DevOps: responsibilities, culture, tooling, and recommendations for building reliable systems.

Azure Active Directory for Developers: What you need to know

Sat, 23 Oct 2021 15:27:17 +0100

What developers need to know about Azure Active Directory: directory services, identity, what modern identity solves and setting up Azure AD authentication.

How to use complex settings in Azure Functions using Options pattern and Dependency injection

Fri, 22 Oct 2021 22:25:15 +0100

Using the options pattern and dependency injection for settings in Azure Functions, and the local.settings.json naming rules I had been ignoring.

Azure functions with Swagger and OpenAPI

Sun, 19 Sep 2021 21:13:56 +0100

How to add Swagger UI to HTTP-triggered Azure Functions in C#: what OpenAPI and Swagger are, and setting up Swashbuckle or the OpenAPI extension.

DevOps, Continuous Integration, Delivery and Deployment

Sun, 29 Aug 2021 16:36:18 +0100

What DevOps, continuous integration, continuous delivery and continuous deployment mean, why they matter and why many companies still don't practise them.

Azure Cognitive Search (formerly Azure Search)

Fri, 27 Aug 2021 11:23:02 +0100

An introduction to Azure Cognitive Search: what an application search engine does, the features and pricing tiers, and where it fits in your architecture.

What is Software Architecture and what does a software architect do?

Sat, 24 Jul 2021 15:37:38 +0100

What software architecture is, what a software architect does and how architecture differs from design, with an example of improving a system's design.

Azure Pipelines and test code coverage for Dotnet core projects

Tue, 29 Jun 2021 11:44:22 +0100

Azure Pipelines and dotnet core test coverage: How to configure your pipeline to generate test code coverage for continuous integration quality checks.

Entity Framework Core: Configure Database Connection using Azure Service Token Provider

Sat, 26 Jun 2021 11:44:22 +0100

Connecting EF Core to Azure SQL with Azure AD access tokens, the right way, using a DbConnectionInterceptor, plus the newer connection-string-only option.

OPENJSON - The Utility function you did not know you needed in a Data transfer Logic App

Mon, 21 Jun 2021 11:44:22 +0100

How SQL Server's OPENJSON function turns one action's JSON results into rows the next SQL step in an Azure Logic App can use, with worked examples.

What is Caching? The different types of caches and interfaces in .NET Core for caching

Sun, 20 Jun 2021 16:50:45 +0100

What caching is, why you can't cache everything, in-memory versus distributed caches, and the interfaces ASP.NET Core gives you for caching in web applications.

What are Azure Logic Apps and How to deploy them using Azure Devops Pipeline - A tutorial and a list of challenges you might encounter

Sat, 12 Jun 2021 11:44:22 +0100

A step-by-step tutorial on building Azure Logic Apps in Visual Studio and deploying them through a CI/CD pipeline, with the challenges you might hit on the way.

Proxy vs Reverse Proxy - What are they?

Sun, 06 Jun 2021 15:25:41 +0100

What a proxy server and a reverse proxy are, what each one is useful for and how they differ, explained simply for developers new to networking.

Git, Case Sensitivity and Github actions

Sat, 15 May 2021 22:50:18 +0100

How a mixed-case project name on Windows broke my GitHub Actions build on Linux: Git's case sensitivity, why it bit me and how to fix and avoid the problem.

Cohesion and Coupling - two important concepts to understand when building good software

Sun, 09 May 2021 22:55:34 +0100

What cohesion and coupling mean in software design, where the ideas came from in structured design, and how they differ, with references for further reading.

Using ProblemDetails in .NET Core 3.1 with C#

Sat, 08 May 2021 15:30:08 +0100

How to return consistent API errors with ProblemDetails in ASP.NET Core: what RFC 7807 problem details are, handling exceptions and customising responses.

.NET (dotnet) Framework and Core and things

Fri, 07 May 2021 21:48:44 +0100

ASP.NET, .NET Framework, .NET Core: what each one is, how they differ, what the ASP part means and how server-side web apps work, explained in plain terms.

Client Side Search for your Hugo Blog with Fuse.js

Sat, 01 May 2021 22:21:16 +0100

How I added fast client-side search to my Hugo blog with Fuse.js and Mark.js: generating a JSON index, the search page and highlighting the matching results.

Event Storming

Sun, 25 Apr 2021 18:41:27 +0100

What Event Storming is and how it uncovers hidden domain complexity: domain events, hotspots, external systems and running Big Picture Event Storming workshops.

Why Domain Driven Design

Thu, 08 Apr 2021 22:38:30 +0100

Why Domain-Driven Design helps tame complex software: how complexity creeps in, how misunderstood problems derail projects, and why talking to users matters.

Good Bye Wordpress. Hello Hugo on Azure Storage

Sun, 04 Apr 2021 17:24:42 +0100

Why I left WordPress for a Hugo static site, deployed continuously from GitHub to Azure Storage behind Azure CDN with GitHub Actions, and how to get started.

Sun, 28 Mar 2021 00:00:00 +0000

Who is Eakan Gopalakrishnan?

Web API Versioning

Fri, 12 Mar 2021 22:35:38 +0000

How to version an ASP.NET Core Web API without breaking the clients that consume it, illustrated with a sample weather forecast API on GitHub.

Managing a team

Wed, 03 Mar 2021 23:21:26 +0000

What I've learnt managing teams since 2015: Paloma Medina's BICEPS model of core human needs at work, and how each need shapes how I manage.

Azure Functions - Overview and tutorial

Sun, 24 Jan 2021 22:44:00 +0000

An introduction to Azure Functions, with a hands-on GitHub tutorial that builds an HTTP-triggered function and sends its output to an Azure Storage queue.

React aka Reactjs

Sat, 23 Jan 2021 20:31:51 +0000

A beginner's overview of React: what the library is, why the virtual DOM matters, and how to build a to-do list app with Create React App, step by step.

Quirky Arrays in C#

Thu, 14 Jan 2021 21:30:16 +0000

Why C# arrays caught me out on a matrix transpose problem: single-dimensional, multidimensional (rectangular) and jagged arrays explained in plain words.

HashSet in C#

Sun, 10 Jan 2021 13:08:58 +0000

How HashSet<T> stores unique elements in C#, with console examples of UnionWith, ExceptWith and SymmetricExceptWith, and a look at its performance.

Windows Terminal and customisations

Thu, 31 Dec 2020 15:58:17 +0000

Setting up Windows Terminal with PowerShell and WSL: installing it, the fonts that tripped me up, a Solarized Dark theme and fixing prompt customisation.

What did I learn as a software engineering manager

Tue, 22 Dec 2020 22:53:51 +0000

What five years as a software engineering manager taught me: leaving coding behind, the role's unseen reality, leadership versus management, and introversion.

Application Insights in .Net Core App

Sun, 20 Dec 2020 12:15:55 +0000

What Application Insights is and how it works in a .NET Core app: adding the NuGet package and instrumentation key, and the telemetry it collects for you.

Semantic versioning - Semver - An introduction - node package manager syntax and quirks

Sun, 06 Dec 2020 18:33:07 +0000

What semantic versioning is and why it matters: major, minor and patch versions explained with examples, and how npm uses caret and tilde in package.json.

Node - Get started

Sun, 06 Dec 2020 17:37:59 +0000

Getting started with Node: what the runtime is, how npm fits in, and the different ways to run JavaScript with it, starting with the REPL mode.

Node and npm: The intro I wish, I got when I began web development

Sun, 06 Dec 2020 14:30:00 +0000

The introduction to Node and npm I wish I'd had: what a JavaScript runtime is, why Node took off, and what npm, its package manager, does for you.

Application Insights, SeriLog and .NET Core

Sat, 28 Nov 2020 07:27:55 +0000

Setting up Application Insights with Serilog in a .NET Core app: what Application Insights does, why logging deserves attention, and how to wire it up.

Feature Toggles

Sun, 08 Nov 2020 16:07:49 +0000

What feature toggles are, the two broad types, and how pairing them with trunk-based development makes continuous integration far less painful.

A static responsive website as an Azure AppService

Sat, 31 Oct 2020 21:06:06 +0000

Building a static responsive website with the viewport meta tag and CSS Flexbox, then hosting it on Azure App Service with a custom domain and an SSL binding.

Entity Framework Core 3.1 - Part 4

Sun, 25 Oct 2020 17:53:59 +0000

Entity Framework Core 3.1, part 4: when to use database views, stored procedures and raw SQL with EF Core, and how to keep them in your migrations.

Entity Framework Core 3.1 - Part 3

Sun, 25 Oct 2020 17:22:33 +0000

Entity Framework Core 3.1, part 3: updating related data when the context isn't tracking it, and working with many-to-many relationships and join tables.

Entity Framework Core 3.1 - Part 2

Sun, 25 Oct 2020 17:16:49 +0000

Entity Framework Core 3.1, part 2: reading and writing data, how change tracking works behind SaveChanges, and logging the SQL EF Core generates.

Entity Framework Core 3.1 - Part 1

Sun, 25 Oct 2020 17:04:36 +0000

Entity Framework Core 3.1, part 1: what an ORM is, what EF Core brings to .NET, and the essentials of data models and migrations you must know.

Containers! Docker! Virtual Machines! What exactly do they do?

Sun, 04 Oct 2020 11:58:01 +0000

When should you use a container? What containers, Docker, virtual machines and hypervisors are, how containers compare with VMs and why Docker took off.

Git: Part 5 - Reset and further

Sat, 03 Oct 2020 13:30:31 +0000

A practical introduction to Git, part 5: undoing changes with git reset, and how git reflog helps you recover work you thought you had lost for good.

Git: Part 4 - Branching and more

Sat, 03 Oct 2020 13:09:57 +0000

A practical introduction to Git, part 4: what branches and HEAD are, and the two ways to integrate changes between branches, merging and rebasing.

Git: Part 3 - Hands on

Sat, 03 Oct 2020 12:39:45 +0000

A practical introduction to Git, part 3: hands-on commands to create a repository, configure Git, check status, make commits and browse the commit history.

Git: Part 2 - Some essential concepts

Sat, 03 Oct 2020 12:36:03 +0000

A practical introduction to Git, part 2: remotes and hosting platforms, cloning and fetching, and how Git stores your work as trees, blobs and commits.

Git: Part 1 - An introduction

Sat, 03 Oct 2020 12:30:48 +0000

A practical introduction to Git, part 1: what version control is and why you need it, how to install Git, and getting started with Git Bash on Windows.

Moving a blog to Wordpress

Mon, 28 Sep 2020 17:41:27 +0000

Why I moved my old Blogger posts to WordPress and how the move works: there's no magic export button, but WordPress's import guide makes it easy.

Software and invisibility

Wed, 16 Sep 2020 20:29:26 +0000

Software development is invisible to most stakeholders. Why '90% done' worries people, and practical ways engineers can make their progress visible.

Software design - Why?

Sat, 27 Jun 2020 14:31:41 +0000

Why jumping straight into code backfires: what software design is, why requirements are never a complete spec, and how a design blueprint helps.

LINQ - watchout for slow queries

Sun, 14 Feb 2016 19:19:00 +0000

Why LINQ queries can get slow: lessons from an inherited job scheduling app whose core table used a GUID primary key as a clustered index, and what to look for.

Password free SSH login to Server using Putty

Sat, 13 Feb 2016 23:29:00 +0000

How to set up password-free SSH login from Windows with PuTTY and PuTTYgen: generating a key pair, installing the public key on the server and saving a session.

Getting to know LINQ

Sun, 27 Jul 2014 20:54:00 +0100

An introduction to LINQ, Language Integrated Query in C#: what it is, the query and lambda syntaxes, and the basics of querying databases with it.

Refactoring - Code written by others

Mon, 21 Apr 2014 01:26:00 +0100

Refactoring a legacy codebase written by others: why special-casing scenarios is the enemy of maintainability, and why I find refactoring rewarding.

Perl Catalyst - VBox Network Configuration on Ubuntu

Sun, 09 Feb 2014 22:35:00 +0000

Running the Perl Catalyst tutorial's virtual machine inside another VM on Ubuntu, and configuring the VirtualBox network adapter and NAT so the nested VM works.

Perl Catalyst Tutorial needs us to download a virtual machine

Sun, 09 Feb 2014 11:29:00 +0000

Getting started with Catalyst, a popular Perl MVC web framework, and why its official tutorial asks you to download and run a ready-made virtual machine.

emacs - Why do I use it?

Sun, 09 Feb 2014 00:01:00 +0000

Why Emacs became my only text editor on Linux: learning it on the job, getting productive with its built-in tutorial, and why good tools make better developers.

Perl module installation - Ubuntu

Wed, 05 Feb 2014 22:59:00 +0000

A quick tip for Ubuntu: install a Perl module from CPAN in a single line with perl -MCPAN -e 'install ModuleName', run with sudo for a system-wide install.

Perl - Modules and path on disk

Sun, 02 Feb 2014 20:51:00 +0000

How to find where a Perl module is installed on disk, so the CPAN module versions behind your scripts stay consistent across different operating systems.

GNU Screen - Dynamic Window Titles, etc - tmux after this

Sun, 02 Feb 2014 04:50:00 +0000

How I use GNU Screen day to day: customising .screenrc, a hardstatus line and dynamic window titles, and why I'd probably pick tmux if I started again.

BASH - keymap and binding

Sun, 26 Jan 2014 13:55:00 +0000

How I used bash's bind and read built-ins to map the up and down arrow keys to history search, so a partly typed command recalls matching history.

GNU Screen - Introduction to terminal multiplexing

Wed, 22 Jan 2014 21:32:00 +0000

An introduction to terminal multiplexing with GNU Screen: why one terminal session with many windows beats juggling PuTTY sessions, and how I came to use it.

Windows 8 and Windows 8.1 shortcuts

Mon, 23 Dec 2013 21:11:00 +0000

A Windows 8 and 8.1 keyboard shortcut you may not know: apps pinned to the taskbar are numbered 1 to 9, and the Windows key plus a number opens each one.

Vertica and K-Safety

Wed, 06 Nov 2013 01:41:00 +0000

What K-safety means in Vertica: how duplicate copies of projections keep the cluster available when nodes fail, and why a table can't go below the system's K.

Perl - Autovivification

Mon, 04 Nov 2013 23:41:00 +0000

What autovivification means in Perl: how assigning to a non-existent entry in a nested hash silently creates the missing levels, and when that can bite you.

Software Engineers should read this

Mon, 14 Oct 2013 10:21:00 +0100

A short recommendation: every programmer should read and understand Martin Fowler's IEEE Software column on making implicit design and behaviour explicit.

SQuirreL graphical user interface for Vertica

Tue, 24 Sep 2013 17:21:00 +0100

Setting up SQuirreL SQL, a free, open-source Java database client, as a graphical interface for HP Vertica: adding the driver, an alias and the connection.

Vertica Query Performance Tuning - An introduction

Thu, 12 Sep 2013 13:36:00 +0100

An introduction to Vertica query performance tuning: how tables map to projections across nodes, and the changes that sped up my own slow analytical queries.

DIR on VMS and display useful information

Wed, 07 Aug 2013 11:20:00 +0100

Making DIR on HP OpenVMS behave more like ls -lrt: options that show versions, dates, owner and size, and why sorting by date needs a script on OpenVMS.

Vertica and its version - Find out using SQL

Mon, 24 Jun 2013 22:09:00 +0100

How to find out which version of Vertica you are running with a simple SQL query, even on a shared development cluster without database administrator access.

Exploring Vertica's INTERPOLATE predicate

Tue, 18 Jun 2013 00:55:00 +0100

Exploring Vertica's INTERPOLATE predicate, which joins tables and fills gaps with the last known value, with simple examples and the case that stumped me.

Vertica - Calendar table with dates from a start date to an end date using analytical SQL

Tue, 18 Jun 2013 00:50:00 +0100

How to build a calendar table of every date between a start and end date in Vertica using plain SQL rather than a stored procedure, with a Stack Overflow link.

Bash v/s Cshell - Functions and their definitions - useful 'type' keyword

Sun, 09 Jun 2013 23:41:00 +0100

Bash has functions and C shell doesn't. How I approximate them with aliases in C shell, and how bash's built-in type keyword shows a function's full definition.

Viewing function definitions in Vertica

Wed, 05 Jun 2013 09:28:00 +0100

Why reading user-defined function definitions from Vertica's USER_FUNCTIONS table truncates them, and how EXPORT_OBJECTS() shows the full source instead.

Setup DBVisualizer with an HP Vertica DB connection

Wed, 05 Jun 2013 00:03:00 +0100

Step-by-step setup of DbVisualizer with an HP Vertica database connection on Windows: installing the JDBC driver, configuring it and connecting to the cluster.

CShell and Absurd quotes and eval

Mon, 03 Jun 2013 20:58:00 +0100

Writing a generic wrapper script in C shell, and fighting its quirky quoting rules and eval along the way. A reminder of why C shell scripting is best avoided.

MySQL Partitioning Tutorial

Mon, 03 Jun 2013 20:57:00 +0100

A pointer to a clear MySQL partitioning tutorial that helped me partition data by how it is accessed, while mapping an object database into a relational one.

VSQL extract data into file

Thu, 30 May 2013 17:34:00 +0100

How to extract query results from a vsql session straight into a file, ready to paste into Excel for someone less familiar with Vertica, without a script.

Vertica DELETE columns from one table using data from another

Thu, 30 May 2013 16:34:00 +0100

How to delete rows in one Vertica table based on matching records in another, when Vertica doesn't support joins in DELETE statements the way MySQL does.

Windows Run box

Tue, 07 May 2013 15:17:00 +0100

A handy list of Windows Run box commands, such as appwiz.cpl and hdwwiz.cpl, that open control panel tools and utilities directly without hunting through menus.

xargs saved my day

Wed, 06 Feb 2013 22:33:00 +0000

How xargs saved my day: working out the disk space used by archived data files spread across nested database directories on Linux, in a single command.

Emacs - Copy Line

Tue, 02 Oct 2012 13:19:00 +0100

A short Emacs Lisp snippet for your .emacs file that copies whole lines to the kill ring, the copying equivalent of kill-line, bound to Meta-k.

Surrogate keys v/s natural keys

Wed, 18 Jul 2012 13:37:00 +0100

Surrogate keys or natural keys? Designing tables for financial securities that carry many real-world identifiers, such as SEDOL, CUSIP and ISIN codes.

Static in C++

Wed, 18 Jul 2012 11:02:00 +0100

The static keyword in C++ means different things in different contexts: variables that live for the whole program, and class members shared by every object.

Mon, 01 Jan 0001 00:00:00 +0000

Foundational learning

https://www.youtube.com/watch?v=U3RkDLtS7uY

Writing policies

The order in which data is written to the cache and the persistent data store will affect the performance of the cache.

What happens if data is written into the cache first?

Writing the data in the cache first, means you can then choose to either:

write synchronously to the persistent datastore and then respond to the client
write to cache and respond to the client but allow writing to the persistent storage asynchronously

The first approach is called Write-through cache. The implications of this approach is that writes will take longer as both the cache and the database are written to and ensured it is successful before a response is sent to the client.

Mon, 01 Jan 0001 00:00:00 +0000

High level design of the Distributed Cache

Functional requirements

insert data into the distributed cache
retrieve data from the distributed cache

NFR

Fast retrieval of data - insert and retrieve should be fast
scalability - distributed cache must be scalable horizontally without bottlenecks
availability - ensure that there is sufficient redundancy to keep the system highly available.
Consistency - The same data retrieved from the cache concurrently should be the same.
Affordability - shouldn’t cost the planet

API

put (key, value)
get (key)

Design considerations

Storage hardware

Make use of commodity hardware where possible to keep costs relatively low. Large data will demand more shards, hence keeping commodity hardware will enable us to scale efficiently.

Mon, 01 Jan 0001 00:00:00 +0000

Evaluating the design

High performance

Consistent Hashing results in O(log(N)) complexity where N represents the number of shards
On a hash server, it takes constant time to retrieve a value using the key O(1)
for eviction in the linked list

Let’s assess the effective access time considering there could be cache hits and misses.

EAT = Ratio (hit) x Time (hit) + Ratio(miss) x Time (miss)

if MFU, we have 10% cache miss and for LRU, 5% cache miss rate

Mon, 01 Jan 0001 00:00:00 +0000

Introduction

A distributed system is inherently complex and hence when something goes wrong, it is difficult to pinpoint what happened unless there is good level of observability.

Observability is the ability to understand what is happening in a distributed system by looking at its external outputs - in this context - logs, metrics, traces etc.

Failures in distributed systems could be attributed to infrastructure - server, network, electrical, etc or due to the application that we care about. One service going down in the system can take down multiple systems across the board if the system is not resilient.

Mon, 01 Jan 0001 00:00:00 +0000

Requirements

all critical processes on the servers must be monitored for crashes
anomalies and overall values in CPU/Memory/Disk/Network bandwidth, average load and so on
hardware component faults - memory failure, slow disk, cpu heat etc
network access - server to server comms
networking components - switches, load balancers, routers, etc
power consumption at server, rack and data centre level
…

Building blocks

Blob storage - to store info about our metrics!

Mon, 01 Jan 0001 00:00:00 +0000

Client side errors

Example of a case where an ISP accidentally released different internet routes. Google customers couldn’t reach google in this case. This was a result of a BGP leak. Border gateway protocol is a routing protocol that connects the entire internet. In a LAN, routing is easy, but as the network grows, it gets complicated.

Thus for routing in the internet, there are special methods. Large organisations and ISPs manage internet connectivity for multipl network sites and locations. Often called Autonomous Systems.

Mon, 01 Jan 0001 00:00:00 +0000

Multiverse Interview Question Bank — With Full Answers

Senior Engineering Manager, Enterprise Trust & Reliability

Interview: 16 September — peer + hiring manager

Everything is here. Each answer is written in first person, in STAR shape, drawn from your Leapsome reviews (2022–2025) and your own prep notes. Read them for shape and detail, then say them in your own words — don’t memorise verbatim.

Where you see [CHECK] — a detail I couldn’t confirm from your documents. Fill it in before the call.

Mon, 01 Jan 0001 00:00:00 +0000

Eakan Gopalakrishnan

Senior Engineering Leader

Engineering Leader with two decades of experience navigating the evolution of high-scale digital platforms in Energy, Insurance, and Finance. I specialize in bridging deep platform infrastructure with customer-facing product delivery: scaling global engineering units and driving operational efficiencies. I lead by operationalizing a true ‘You Build It, You Run It’ culture, fostering autonomous teams that treat reliability as a core feature.

🧑‍💻 Professional Experience

Senior Engineering Manager

2025-07-15 - Present

Kaluza

An intelligent retail energy platform powering the future of energy.

London, United Kingdom

Orchestrated the rapid scaling of autonomous software engineering teams for delivering Global Energy Commerce capabilities.

OpenSSF Scorecard

Mon, 01 Jan 0001 00:00:00 +0000

A Hugo page that renders the latest OpenSSF Scorecard findings from workflow-generated data.