lean-software-development

The seven principles from Mary and Tom Poppendieck are eliminate waste, amplify learning, decide as late as possible, deliver as fast as possible, empower the team, build integrity in, and see the whole. They translate Toyota Production System thinking into software development practice.

The seven wastes are partially-done work, extra features, relearning, handoffs, task switching, delays, and defects. Each maps to a manufacturing waste from Toyota's system, and identifying the dominant one in your value stream reveals the biggest leverage point for improvement.

Lean is the broader operational philosophy and mindset; Kanban is one tool that operationalizes specific principles like eliminating waste, delivering fast, and seeing the whole. Adopting Kanban without the lean mindset produces cargo-cult lean where the tools feel like overhead.

It means making commitments at the last responsible moment, when deferring further would forfeit a valuable option. Real Options thinking makes the deadline explicit so deferral is disciplined waiting for information, not procrastination or decision avoidance.

Use set-based design when uncertainty about the right solution is high, the cost of being wrong is significant, and multiple options can be explored cheaply in parallel. It keeps alternatives alive until information arrives to eliminate them, avoiding costly restarts.

Common pitfalls include cargo-cult lean (tools without mindset), equating lean with cost cutting, deferring decisions forever, cutting buffers without diagnosing the system, and measuring individual utilization while claiming to empower teams. Local optimization that pushes problems downstream is another frequent failure.