The Fianto blog, page 7.
Notes on USDC subscriptions on Solana: how renewals are collected, what Fianto ships, and the numbers behind it.
Older posts.
Can anyone see my revenue? Privacy on a public blockchain for merchants
Yes. Anyone who knows your receiving wallet's address can see every USDC payment into it on Solana: the amount, the time and the paying wallet, and from that a fair estimate of your revenue. What they cannot see from the chain is who the wallets belong to, what was bought, or your order IDs and customer emails, which Fianto keeps off chain. Fianto has no privacy feature that hides payments; the honest mitigations are about which wallet you use and what you link to it.
StablecoinsMiCA and stablecoins: what EU businesses can accept, from the regulation and the regulators
MiCA, the EU's Markets in Crypto-Assets Regulation, addresses its rules to stablecoin issuers, people who offer crypto-assets to the public and crypto-asset service providers. An e-money token, a stablecoin that tracks one currency, may be offered to the public in the EU only by its issuer, authorised as a bank or e-money institution with a published white paper, or by others with the issuer's written consent; as of 15 October 2026 ESMA's register lists Circle's EU entity, authorised in France, with a USDC white paper. This post quotes the regulation and the regulators with dates, is not legal advice, and does not say whether MiCA applies to your business.
WalletsCan I pay from Coinbase or Binance instead of a wallet?
No: a Fianto checkout needs a wallet that signs a Solana transaction in your browser, and a balance on an exchange such as Coinbase or Binance has no way to do that. Withdraw the USDC on the Solana network to a wallet you control, add a little SOL for the network fee, and pay from that wallet. The same wallet is the one you later use to manage or cancel a subscription, so pick one you will keep.
SolanaWhat is an associated token account? Why your USDC has its own address
An associated token account is the default account that holds one token for one wallet on Solana, at an address calculated from the wallet's address, the token program and the token's mint. Your wallet address never holds USDC itself: the USDC sits in that second account, which must exist before anything can land in it. With Fianto, a merchant's receiving wallet needs one before its first sale and a customer's wallet needs one to pay, and Fianto never creates either.
StablecoinsWalletsReal USDC on Solana: the mint address, and native vs bridged USDC
Real USDC on Solana is the token whose mint address is EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v, the address Circle publishes for USDC on Solana mainnet. Anyone can create a token called USDC with the same symbol and logo; nobody can give it that address, so the address is the check. Fianto's checkout accepts only this native mint: bridged versions of USDC and lookalikes are different mints, and a wallet that holds only those cannot pay.
WalletsHow to see and revoke token approvals on Solana
A token approval on Solana is a delegate set on one of your token accounts: an address allowed to move tokens from it, and each account holds only one at a time. You can see and remove it in some wallets (in Solflare, under Settings, Security & Privacy, Spending approvals) or with the spl-token command line, and revoking takes effect at once. Before you revoke the delegate on your USDC account, check whether it belongs to the Solana Subscriptions program: that single approval is shared by every subscription your wallet pays through the program, so removing it makes each of them fail at its next renewal.
Solana"Blockhash not found": why a Solana payment expires if you wait to sign
"Blockhash not found" means the transaction names a recent block that the network no longer accepts, or does not know yet, so it will never be processed. Solana only takes a blockhash up to 151 blocks old, which makes every signed transaction a short-lived object: wait too long in the wallet and it expires unsent. Nothing moves and no fee is charged; the fix is to build a fresh transaction and sign it promptly.
ProductCoupon recipes for USDC plans: five discount codes and how to set them up
Good discount codes for a USDC plan come from four settings: a percentage or fixed amount, how many charges it lasts, an expiry, and a redemption limit. With them you can build a first month at 99% off in place of a free trial, a founders code that runs forever, a code that only works on yearly plans, a one-person code and one code per partner. Every recipe has to respect one rule: the price after the discount must stay at least 0.01 USDC, or the code is refused.
WalletsSolana wallet drainers and fake payment requests: how to spot a malicious transaction
A Solana wallet drainer is a website or app built to make you sign a transaction that hands your tokens, or control over your token accounts, to someone else. Nothing it does can be undone once the transaction lands, so the only defence is reading the request before you approve: who gets paid, how much, and whether it contains anything other than a transfer. A genuine Fianto one-off payment, served from checkout.fianto.xyz, holds one USDC transfer of the price to the merchant, plus a second transfer to Fianto only when there is a Fianto fee, and there is none during the beta.
WalletsPhantom and Solana wallet warnings: "This transaction may be unsafe" explained
Phantom's simulation warning means the wallet could not predict what a transaction will do, and its new-domain notice means Phantom has not reviewed the site yet; neither is a finding that the transaction is malicious. Phantom's FAQ lists three causes for its simulation warning: more than one signer, a transaction close to Solana's size limit, and a transaction that would fail. Treat any warning as a reason to read the request yourself, and on a Fianto checkout a one-off payment should show only the Total leaving in USDC plus a small SOL fee.
WalletsWhy your wallet doesn't show at checkout
A Fianto checkout shows only the Solana wallets that announce themselves to the page through the Wallet Standard, and it can pay only with those that can sign a transaction without sending it. A wallet that is installed in another browser, switched off, blocked in a private window or open only on your phone does not appear as installed; one that appears with the tag "Cannot sign here" can only sign and send in one step. The fix is to open the page where the wallet runs, or to pay with a wallet that offers sign-only signing.
SolanaDataHow much does a Solana transaction cost? Base fee, priority fee and real payment numbers
A Solana transaction costs a base fee of 5,000 lamports (0.000005 SOL) per signature, plus an optional priority fee set by the compute-unit limit times the price per unit. A USDC payment through Fianto costs the customer 5,060 lamports, a first subscription 10,400 lamports, and a cancel or rent reclaim in the portal 5,100 lamports; the checkout shows its fee line as "paid by you, under $0.01". Rent for new accounts is separate from the fee, and the merchant pays none of it.