LightMySky

The Project Arc: Building a Program in Stages

Taking a project from a written aim to working software in stages: a thin version that runs end to end, then features added one at a time, each kept working. Refactoring is the step that keeps the code liveable as it grows.

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What a learner can do afterwards

  • Break an aim into stages where every stage leaves a program that still runs
  • Keep a small backlog and say what the next stage is and why it is next
  • Refactor once the shape of the code has drifted, without changing what it does

1 · Read

Software engineering builds in a planned way instead of hacking until something works. You write a short plan naming the aim, the main parts, and how you will test each part. Skipping that thinking buys painful rewrites later.

Try it together

You start with a walking skeleton, the simplest end to end job, like a quiz asking one question and checking the answer. Then you add one slice per stage while the program keeps running. You hold remaining work as a small backlog, an ordered list whose top item is always the next stage.

You pick the next stage for a stated reason: it unlocks later work, cuts the biggest risk, or delivers the most value. Say the reason aloud, since a stage with no reason is usually the wrong stage. A light plan also exposes risk early, so you can reorder or shrink the aim in time.

Good to know

You refactor once the code shape has drifted, while everything still works. Refactoring reshapes the code without changing what it does, so later stages land on a tidy base and stay fast.

Thin running start, one reasoned slice per stage, and tidy the shape as it drifts.

2 · Watch

Take it off screen

Print a worksheetA4 with an answer key page for grown-ups. No screen, no internet.

Where it sits

Then practise

8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.

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The Project Arc: Building a Program in Stages · Computing, ages 17 to 18 · LightMySky