Gitcoin-style matched funding: contributions flow directly to projects, and a matching pool is distributed by the quadratic formula (many small donations > a few big ones). Matching is computed transparently off-chain and distributed by the round admin.
Matching formula: match ∝ (Σ√contribution)² − Σcontribution, capped by the pool. The admin calls finalize() with computed amounts. This UI does contributions; matching computation is off-chain per round.