Rail SDK
A software kit that POS companies and payment processors add to their firmware or applications, turning machines already on counters into Solana-capable endpoints.
The rail behind the register. Built for Solana.
Mainstreet builds the software that lets existing point-of-sale systems, payment processors, and online stores accept Solana payments.
- Rail SDK
- Embedded into existing commerce systems
- Gateway
- Transactions wired to Solana
- Two fronts
- Physical retail and e-commerce
What we're buildingExplore the stack
One payment layer. Three ways into commerce.
The integration surface changes. The underlying rail stays the same.
Gateway backend
The common connection behind every integration. It prepares transactions, routes them to Solana, tracks confirmation, and returns settlement state to the commerce system.
E-commerce stack
A direct integration path for online stores and commerce platforms that need the same payment and settlement capabilities without a physical terminal.
Two fronts
Physical retail and e-commerce, supported through one gateway and one settlement path.
Two fronts
Physical retail
Meet merchants where they already sell.
Integrate with the POS lines and processors already deployed across stores, restaurants, service counters, and venues. No new hardware and no parallel checkout flow.
E-commerce
Bring the same rail online.
Give stores and commerce platforms a direct path into the gateway, with transaction state and settlement designed for modern online checkout.
Transaction path
One connection from checkout to chain.
- 01
Customer wallet
- 02
POS or checkout
- 03
Mainstreet gateway
- 04
Solana
- 05
Merchant settlement
The commerce system sends a payment request to Mainstreet. The gateway prepares and observes the Solana transaction, then returns a clear result to the register or checkout so the merchant can complete the sale.
Why Solana
A register does not wait.
Checkout is an unforgiving environment. Solana combines low transaction cost, global reach, and a path toward confirmation times that fit ordinary commerce.
- 400ms → 350msMainnet
- 350ms → 300msNext
- 300ms → 250msPlanned
- 250ms → 200msTarget
Payment infrastructure wins when it disappears into the systems merchants already use.
Distribution
The integration is the distribution.
Merchants already use POS systems that support several payment methods. They choose optionality and ease of use, not a machine dedicated to one way to pay.
Mainstreet does not need to manufacture hardware or convince merchants one by one. The first objective is to integrate with a popular POS line and make Solana another payment option on equipment already in the field.
One signed integration can reach the merchants that already rely on that system. Each additional POS line and processor expands the same gateway across a larger installed base.
Win the channel once. Reach every merchant behind it.
Why it hasn't been done
The old systems own the market.
Processors and POS companies move slowly because their systems are mature, regulated, and deeply embedded. They also own nearly all merchant distribution.
Comparable timeline
≈ 8 months
A comparable VisaNet integration took roughly eight months from kickoff to certification.
Relationships
Business-development access and signed commercial agreements come before code reaches production.
Certification
Hardware, software, security, transaction, and operational testing create long lead times.
Patience
The market is slow and concentrated. Infrastructure that survives the process becomes difficult to displace.
Why choose usTalk integration
Smarter rails. Less hassle. More control.
The same payment moment, handled by infrastructure built for it.
Reaching merchants
Sell and ship dedicated hardware to one merchant at a time.
One signed POS integration reaches every merchant already on that system.
Checkout experience
A separate crypto flow sitting beside the register.
Solana appears as one more payment option inside the existing checkout.
Settlement state
Confirmation handled outside the commerce system.
The gateway observes the transaction and returns a clear result to the register.
Certification
Every merchant integration restarts the same long process.
The certification work is done once, then reused across the installed base.
The futureRead the full documentation
Roadmap. Built in order.
Infrastructure first, then the channel, then the installed base.
- Phase 01
Build
Build the Solana rail SDK and gateway backend.
- Phase 02
Integrate
Sign and integrate a first popular POS line; launch the e-commerce stack.
- Phase 03
Scale
Expand across additional POS lines and processors; scale merchant distribution.
- Next
Coming soon
Further rails and processor coverage, announced as agreements are signed.