| API | Application Programming Interface - a set of rules and protocols for interaction between software components |
| Blockchain | A distributed database consisting of a chain of blocks, each containing a cryptographic link to the previous one |
| Smart contract | A program that automatically executes and enforces agreement conditions on a blockchain. Its code is stored and executed on the network, without intermediaries, according to predefined rules. |
| SDK | Software Development Kit - a collection of software development tools that allows developers to create applications for a specific platform or integrate with a service |
| Non‑custodial | A model in which the service does not store private keys and does not control user funds; the user manages them independently and can withdraw funds from their smart contract at any time. |
| Stablecoin | A type of cryptocurrency designed to maintain stable value by being pegged to a reserve asset, typically the US dollar in a 1:1 ratio |
| Visa | International payment system that processes electronic payments worldwide through a network of issuing banks and acquirers, supporting debit and credit cards |
| Bank issuer | A financial institution that issues payment cards and is responsible for card-based transactions, acting as the issuer in the payment ecosystem |
| Счет | Software wrapper over a smart contract that transforms the contract itself into a user-friendly “banking” account. |
| SEPA | Single Euro Payments Area - a unified euro payment zone that provides simplified cashless transfers between banks in participating countries (EU, EEA, Switzerland, UK and others) as easily as within one country |
| SWIFT | Society for Worldwide Interbank Financial Telecommunications - an international bank transfer system through the SWIFT network, allowing money to be sent to any country and currency, but usually with higher commission and longer timeframes than SEPA |
| Mica | Markets in Crypto-Assets Regulation (EU) 2023/1114 - European Union regulation that establishes a comprehensive regulatory framework for crypto-assets and crypto-asset service providers |
| Регулятор | Competent authority responsible for overseeing and regulating financial services, such as Česká národní banka (CNB) for crypto-asset service providers under MiCA |
| TON | Toncoin (TON) is the native cryptocurrency of The Open Network (TON), a decentralized blockchain created for fast transactions and convenient integration with the Telegram ecosystem. |
| Solana | A high-performance blockchain platform that supports smart contracts and decentralized applications, with SOL as its native cryptocurrency and support for stablecoins like USDC and USDY |
| Gas | Transaction fees required to execute operations on a blockchain network, used to compensate validators for processing and validating transactions |
| Validator | Network participants responsible for verifying and validating transactions on a blockchain network |
| Backoffice | Internal administrative system used by the company to manage operations, monitor transactions, conduct compliance checks, and maintain customer records |
| Spending account | Accounts in Holders designed for linking cards and making purchases |
| Savings account | balances of the connected wallet in various currencies, used for storing funds |
| Changelly | A cryptocurrency exchange service integrated into Holders for topping up accounts with popular stablecoins |
| USDT | Tether USDt (USDT) is a stable cryptocurrency developed by Tether, based on blockchain technology and pegged to the US dollar at a 1:1 ratio. It was created to combine the stability of traditional money with the convenience and speed of cryptocurrency transactions. |
| USDC | USDC (short for USD Coin) is a stablecoin created in 2018, designed to maintain stable value by pegging to a reserve asset. In the case of USDC, it is backed by the US dollar in a 1:1 ratio, meaning each token can be exchanged for one US dollar or equivalent asset stored in reserve. |
| USDY | Ondo US Dollar Yield (USDY) is a tokenized financial instrument that combines the convenience of stablecoin usage with yield from ultra-safe US Treasury bonds and bank deposits. It is primarily designed for investors outside the United States. |
| Controller | A component in the system architecture responsible for managing blockchain interactions, transaction processing, and smart contract operations |
| Triple-A | A payment partner used by Holders for processing SEPA and SWIFT transfers, handling fiat currency transactions manually through support agents |
| IBAN | International Bank Account Number - a standardized format for identifying bank accounts used in SEPA transfers and international banking |
| Treasure wallet | Corporate cryptocurrency wallets used by the company to manage and store digital assets for operational purposes |
| Account brand | An identifier that indicates the source of account creation in the system. |
| Wallester | A card issuer partner that provides payment card services and processes card-based transactions for Holders users |
| KYC | Know Your Customer - identity verification procedures required for all users before accessing crypto-asset transactions, performed using external verification providers like Sumsub |
| AML | Anti-Money Laundering - compliance measures and monitoring systems used to detect and prevent money laundering, including transaction screening and risk assessment |
| Apple Pay | A mobile payment service by Apple that allows users to make payments using their Apple devices, requiring specific certificates for integration |
| Google Pay | A mobile payment service by Google that enables contactless payments through Android devices, requiring specific certificates for integration |
| Bank statement | An account statement is a document that reflects all operations on a client’s account for a selected period in the account currency: incoming transactions (returns, deposits) and expenses (payments). |
| Account ownership certificate | The certificate verifies the ownership rights of a specific individual to decentralized accounts in the Holders system. |
| Travel Rule | Travel Rule is an anti-money laundering (AML) requirement under which transfers between financial institutions (banks, cryptocurrency exchanges, and others) must include basic information about the sender and recipient (including name, account number/address, in some cases residential address and other data) along with the payment. |
