Foundry is the engine behind Paying.co's certifications — a native EMV L3 lifecycle written once, with each processor added as a thin, swappable adapter.
Native C99 core. Android/Kotlin SDK rides on top as a wrapper.
Every EMV L3 engagement repeats the same lifecycle. Foundry writes that lifecycle once and treats the processor as the only part that changes.
Canonical model, BER-TLV parser, hardware abstraction, the transaction engine and crypto — roughly 75% of every certification, built and battle-tested.
A new engagement means implementing one seam. Only authorize() differs per processor — credentials live in the injected transport, never the adapter.
Because the core arrives already proven, the work — and the timeline, and the cost — collapses to the adapter and the test scripts.
One normalized transaction shape and a full TLV parser + view engine feeding every adapter.
Exponent-aware minor units in one module — JPY (0), USD/MXN/EUR (2), BHD/KWD (3) — no adapter guesses on its own.
Key provisioning and the crypto seam built into the core, ported intact to native C.
Sale, pre-auth, completion, void, refund and get — with an idempotency store and clean in-band error codes.
/* The only seam a new processor implements */ fdy_status_t authorize( const fdy_txn_t *txn, const fdy_creds_t *creds, // held by transport fdy_auth_result_t *out ) { // map canonical → processor request // send via injected HTTP transport // map response → canonical result return FDY_OK; } /* everything else — lifecycle, TLV, money, crypto — is already done. */
Every casting on the roster is live and shipping today — a growing engine that adds one processor at a time.
UCP REST casting, fully multi-currency.
Transit-focused adapter, intentionally USD-only.
NAB Velocity casting.
ISO 8583, MXN — via Prosa, Mexican acquiring.
Via NAB, Custom Pay XML casting.
EPG casting, multi-currency.
Visa Platform Connect casting.
A second TSYS path, alongside the TransIT adapter.
Foundry's core was ported 1:1 to native C99 — no Android, JVM, or coroutine dependencies. Embed it on unattended terminals, kiosks, or behind any language's FFI, with the Android/Kotlin SDK riding on top as a wrapper.
Reconnect on an EMV L3 engagement and put 132 certifications' worth of tested groundwork to work on yours.