I am one of the engineers who built this. Column is an OCC-chartered bank with its own in-house built banking core, so the processor runs on the same core as our ledger and payment rails.

We have direct integrations with Visa and Mastercard. It supports credit, debit, charge, fleet, prepaid, and stablecoin-backed programs, and what you'd expect from a mature issuer processor out of the gate: 3DS, digital wallets, Level 3 data, disputes, spend controls, and card manufacturer integrations.

Happy to answer questions!