1. How Software Actually Runs
From the text you type to electrons doing work
The journey of one line of code
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The curriculum
8 tracks, 56 modules, in the order they are meant to be taken. The 8 free preview modules below are fully playable — the animated diagram on this page is the same one paying learners work through.
1. Foundations
BeginnerHow software actually runs, and the building blocks of every program you'll ever write.
Free preview
2. Programming Building Blocks
Variables, control flow, and functions — the grammar of every language
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3. Thinking in Data
Arrays, objects and JSON — your general ledger for the digital world
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4. The Command Line
The one interface that composes, scripts, and never changes out from under you
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5. How the Internet Works
Everything between the browser and the server — DNS, TCP, TLS, and the anatomy of one request
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6. Debugging as a Discipline
A repeatable method, not luck — reproduce, read, isolate, and change one thing at a time
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2. Core Engineering
Beginner → IntermediateData structures, algorithmic thinking, version control and testing — the craft under the craft.
1. Data Structures That Matter
Stacks, queues, hash maps and trees — and when each one wins
Watch the same four jobs flow through a stack and a queue
STACK · LIFO · exit at top ↑
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QUEUE · FIFO · exit at front →
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3
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1
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2. Algorithms & Big-O, Practically
Why some code stays fast at 10,000 records and some collapses
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3. Version Control & Testing
Git as your audit trail; tests as your internal controls
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4. Recursion & Trees in Practice
A function that calls itself, the structure it was made for, and when a loop is plainer
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5. Concurrency Basics
Doing more than one thing at once without the folklore — sync vs async, the event loop, and the race
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6. Reading Other People's Code
The skill nobody teaches and every professional needs — comprehending code you didn't write
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3. Full-Stack Web
IntermediateThe request lifecycle, React, APIs and databases — your working stack, understood deeply.
1. The Request Lifecycle
What actually happens in the 300ms after a user taps a button
One tap → one response: the full round trip
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2. React: State Drives the Screen
Components, props, state — and the render cycle that ties them together
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3. Backend, APIs & Databases
REST design, SQL thinking, and why indexes change everything
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4. Auth, End to End
What logging in actually is — session, cookie, hash and the round trip a single user makes to sign in
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5. File Uploads & Storage
The deceptively hard feature — multipart, server-side validation, signed URLs and serving files back safely
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6. Forms, Validation and Error States
The engineering of a form that doesn't punish people — controlled inputs, dual validation and error handling in code
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4. System Design & Architecture
Intermediate → AdvancedScaling, data at scale, and event-driven architecture — including the ledger pattern you already use.
1. Scaling Fundamentals
Vertical vs horizontal, load balancers, and why stateless wins
Horizontal scaling: a load balancer spreading traffic
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2. Data at Scale
Caching, replication, and the trade-offs behind every fast system
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3. Event-Driven Architecture & the Ledger Pattern
Immutable events, projections, and queues — double-entry thinking for systems
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4. Data Modelling That Survives Contact
Entities, keys and constraints — why a schema that doesn't reconcile is a set of books that doesn't balance
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5. Changing a Live Database
Expand, backfill, contract — schema evolution without downtime or data loss
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6. Idempotency, Retries and Exactly-Once
Networks fail after the work is done — building safety into the retry, using payments as the example
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5. Business Process Digitization
AppliedReengineering processes and translating them into software — where your accounting instincts become an unfair advantage.
1. Business Process Reengineering 101
Don't pave the cowpaths — redesign the process, then digitise
As-is vs to-be: a purchase approval, reengineered
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2. From Process Map to Software
Actors, states and events — the translation layer between BPR and code
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3. Automation & Human-in-the-Loop
Approval gates, notifications, and audit trails that clients trust
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4. Reporting and Reconciliation
Why two reports disagree, and how to build numbers people will sign their name to
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5. Compliance, Audit and Retention
Building software for work that has to answer to somebody
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6. Getting Off Spreadsheets
Migration and cutover — the change-management project wearing an engineering costume
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6. Design & Product
AppliedWhy some products feel world-class and most don't — the craft layer AI generates badly and users judge instantly.
1. Why Your App Looks Amateur
Spacing, type and colour as a system — most bad design is inconsistency, not bad taste
One base unit cascading into every screen you ship
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2. The Paths Nobody Demos
Empty, loading, error and success — the four states AI-generated code always omits
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3. Taste Is Mostly Editing
Deciding what to build, what to refuse, and when to stop
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4. The First Five Minutes
Onboarding and activation — where the value proposition becomes real or is exposed as a claim
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5. Information Architecture
Naming, grouping and the list view — how people build a mental model of your product
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6. The Words Are the Interface
Microcopy — the cheapest quality upgrade available to any software product
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7. Advanced & AI-Native
AdvancedSecurity, DevOps and AI-native engineering — shipping systems people can bet a business on.
1. Security Essentials
Authentication, authorization, and the mistakes that sink products
Two locked doors: authn, then authz, on every request
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2. DevOps & CI/CD
Environments, pipelines, and knowing your system is healthy
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3. AI-Native Engineering
LLMs as components: prompts, RAG, agents, and cost discipline
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4. Auth, Sessions and Multi-Tenancy
Who you are, what you may do, and proving the database refuses everyone else
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5. Secrets, Config and Supply Chain
What must never reach the browser, and what you inherited the moment you installed that package
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6. Reviewing AI-Generated Code
The constraint has moved from writing code to judging it
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8. Ship It: Zero to Deployed
CapstoneStop learning about systems and build one. Follow a real app from empty repo to deployed, with auth, a database you can trust, payments and a live URL — your choice of two projects.
1. Before You Start
Install the handful of free tools and create the free accounts you'll build on — then verify each one before you touch Step 1.
The interactive walkthrough for this preview is being published.
2. Set Up the Spine
Clone the template, wire your own Supabase, and deploy a live app to a real URL before you build a single feature.
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3. Auth You Can Trust
Email + password auth with a session that survives a refresh and a gate a signed-out visitor can never slip past.
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4. Your First Table, Locked Down
Your first tenant-scoped table, with isolation proven at the database by a runnable test — not trusted from the UI.
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5. Forms That Don't Lie
CRUD with the four states AI skips — idle, submitting, success, error — and never lose what the user typed.
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6. Money In
Take a test payment, mark the account Pro through a webhook you can safely replay, and gate a feature at the server.
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7. Workspaces & Multi-Tenancy
One app, many businesses — every client and invoice isolated to a workspace at the database, not by a WHERE clause you hope you remembered.
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8. The Append-Only Ledger
The centerpiece: never store a balance you can derive — record immutable events, replay them into the balance, and correct with a reversal, never an edit.
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9. Invoice Lifecycle + Pay-Link
A DB-enforced state machine (draft → sent → paid), marking-paid that records a settling ledger event, and a public read-only pay-link a logged-out client can open.
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10. Ship It
Stripe on the pay-link, a webhook that records the payment to the append-only ledger idempotently, and a live URL — verified end to end.
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11. Model the Content
profiles, collections and items under your own @handle — and RLS that makes 'private' provably private
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12. Public by Design
cookieless anonymous reads + ISR + a per-collection OG card — and RLS, not a filter, hides the private lists
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13. Free vs Pro
the S5 Stripe gate, applied to Shelf: private collections require Pro — enforced by a DB trigger, not the UI
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14. Ship It & Share
robots + sitemap + a friendly 404, then a real deploy — where 'done' is the verified end state, not a tool saying OK
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Unlock every module
All-access opens all 56 modules from $24/mo and includes whatever is added while you are subscribed — access ends when you cancel. Or take a single module for $39, or lifetime access for $599 once, both of which are permanent.
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