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Practices
BP #2: Concept Lock on Day 1

BP #2: Concept Lock on Day 1

Lock all critical design decisions within the first 4–6 hours. Core mechanic, art direction, win condition, scope: decided and committed before real production starts.

“Important design decisions should be made on the first day instead of delaying them.” — Colossorama (LD36) [1]

Why It Works

Late design decisions do not arrive alone. Every system built before a late decision may need to change around it. The earlier the lock, the more build time stays intact.

JorgeGameDev learned this the hard way. In Colossorama (LD36) the upgrade system was not fully designed until the second day. That one decision forced cuts across the board because content that was already planned no longer fit what the system allowed. [1] The jam did not run out of time because of scope. It ran out of time because a core mechanic arrived too late to shape everything else around it.

What to Lock

  • Core mechanic (what does the player actually do?)
  • Win/loss condition
  • Art style and asset constraints
  • Architecture approach (how do systems connect?)
  • Hard feature list: what is definitely in and what is definitely out

Do not lock polish or level count. Lock the things that, if changed later, break other things.

How to Apply

After BP #1 (ideation), run a 30-minute concept lock session:

  1. State the core mechanic in one sentence
  2. Sketch the architecture on a whiteboard or shared doc
  3. Write the Must/Should/Could/Won’t list (see BP #3)
  4. Everyone confirms understanding. No ambiguity allowed.

Once locked, treat changes as scope cuts only. You can remove. You cannot redesign.

Methodology Connection

Methodology Connection

Stage-Gate uses explicit decision points with go/kill criteria before each phase of development. In full production this is a formal gate review with documentation and sign-off. At 48-hour scale it is a 30-minute session at hour 4–6 that performs the same function: nothing moves forward until the design is agreed on.

Related

BP #1: Time-Box IdeationBP #3: MoSCoW