Principles

In this section, we list the principles that we follow when developing products. We use these principles as a base to create all processes, tools, guidelines, and workflows of all departments—product, design, and engineering.

These principles are based on the book The Principles of Product Development Flow by Donald G. Reinertsen.

Each principle has an id made of its chapter's prefix and its number, such as E3 or FF7, and each chapter has its own page:

Chapter	Ids	What it covers
The Economic View	E1–E21	Every decision as a life-cycle profit trade-off, with cost of delay as the key number
Managing Queues	Q1–Q16	Why invisible queues cause most of the waste, and how to measure and control them
Exploiting Variability	V1–V16	When variability creates value, and how to reduce its cost instead of its amount
Reducing Batch Size	B1–B22	How smaller batches cut cycle time, risk and overhead, and how to pick the size
Applying WIP Constraints	W1–W23	Limiting work in process to control cycle time and flow
Controlling Flow Under Uncertainty	F1–F30	Cadence, synchronization and sequencing when loading and durations vary
Using Fast Feedback	FF1–FF24	Fast feedback loops and the metrics that steer the work
Achieving Decentralized Control	D1–D23	Decentralizing decisions with shared intent, clear boundaries and trust