The default leaf policy explicitly favors payment convenience over exit value

What the evidence shows

Technical and product details

1. SDK design

   Breez 0.23 documents a direct tradeoff: more, smaller leaf denominations improve routine payment execution, while fewer, larger leaves cost less to exit. 1

   Supporting material shown on this page

   Breez leaf optimization and exit costPinned source code · github.com · checked 2026-08-24

   40## Leaf denominations and exit cost
   41
   42Every leaf is exited by its own chain of transactions, so it carries its own on-chain fee whatever its value. The more leaves your balance is spread across, and the smaller they are, the more of it goes to fees on the way out, and the more low-value leaves an {{#enum ExitLeafSelection::Auto}} exit a
   43
   44How the balance is split into leaves is governed by the SDK's leaf optimization, which balances everyday payment experience against unilateral exit value. More, smaller denominations let payments go out without leaf swaps, while fewer, larger denominations cost less to exit. The default leans toward

2. Default choice

   The guide says its default leans toward payment experience because unilateral exit is treated as a rare last resort. 1

   Supporting material shown on this page

   Breez leaf optimization and exit costPinned source code · github.com · checked 2026-08-24

   40## Leaf denominations and exit cost
   41
   42Every leaf is exited by its own chain of transactions, so it carries its own on-chain fee whatever its value. The more leaves your balance is spread across, and the smaller they are, the more of it goes to fees on the way out, and the more low-value leaves an {{#enum ExitLeafSelection::Auto}} exit a
   43
   44How the balance is split into leaves is governed by the SDK's leaf optimization, which balances everyday payment experience against unilateral exit value. More, smaller denominations let payments go out without leaf swaps, while fewer, larger denominations cost less to exit. The default leans toward

3. User consequence

   A wallet's ordinary optimization policy can increase the number of separately fee-bearing exit paths and abandon more small leaves as uneconomical dust during the emergency. 1

   Supporting material shown on this page

   Breez leaf optimization and exit costPinned source code · github.com · checked 2026-08-24

   40## Leaf denominations and exit cost
   41
   42Every leaf is exited by its own chain of transactions, so it carries its own on-chain fee whatever its value. The more leaves your balance is spread across, and the smaller they are, the more of it goes to fees on the way out, and the more low-value leaves an {{#enum ExitLeafSelection::Auto}} exit a
   43
   44How the balance is split into leaves is governed by the SDK's leaf optimization, which balances everyday payment experience against unilateral exit value. More, smaller denominations let payments go out without leaf swaps, while fewer, larger denominations cost less to exit. The default leans toward

Scope control

What this does not establish

• This is a configurable wallet policy, not a fixed protocol multiplier. The SDK exposes the tradeoff, and wallets can choose an exit-favoring configuration. 1

Sources and excerpts

Primary sources

The relevant details and available source-code excerpts appear alongside the claims above. This list preserves the complete original-source trail for independent verification.