The bonding curve
What are the starting parameters?
The curve uses constant-product pricing with virtual offsets. Buys increase the effective SOL reserve and decrease the effective token reserve; sells do the reverse.
| Parameter | New version-2 market |
|---|---|
| Real SOL at creation | 0 SOL |
| Virtual SOL offset | 30 SOL |
| Real token vault at creation | 1,000,000,000 tokens |
| Virtual token offset | 73,000,000 tokens |
| Effective starting token reserve | 1,073,000,000 tokens |
| Tokens available before graduation | 793,100,000 tokens |
How is a trade calculated?
Let S = real SOL reserve + 30 SOL and T = vault tokens + 73 million tokens. Let B be buy input after the platform fee, and A be the token amount being sold.
The program calculates in integer lamports and token base units, rounding outputs down. A final buy is capped to the remaining sellable token allocation and its required input is rounded up. A sale is rejected if its gross output exceeds the real SOL reserve.
| Quantity | Formula |
|---|---|
| Buy output | floor(T × B ÷ (S + B)) |
| Gross sell output | floor(S × A ÷ (T + A)) |
| Net sell output | Gross sell output minus the rounded-up 1% SOL fee |
| Spot price | S ÷ T |
Why does 30 SOL not mean graduation at 30 SOL?
The 30 SOL is virtual, so it shapes the starting price without being deposited. Graduation happens when 793.1 million tokens have left the vault through net buying, leaving 206.9 million actual tokens.
Ignoring integer rounding, the launch invariant starts at 30 × 1,073 million. At the final inventory, the effective token reserve is 206.9 million + 73 million = 279.9 million. The required real SOL is therefore (30 × 1,073 ÷ 279.9) − 30, or about 85.005359057 SOL. Platform fees are additional and never count as liquidity.
Is this identical to Pump.fun?
New markets use Pump-style SOL launch parameters, but Bundless has its own programs, fixed 1% fee, approval hook, and graduation pool. It does not migrate to PumpSwap.
Older version-1 markets retain their 0.1 SOL virtual reserve and 0.3 SOL graduation threshold. They are labeled Demo curve. Their stored curve version is used for quotes and history; new economics do not rewrite those existing markets.