# Twisp

> Twisp provides ledger infrastructure, payment processors, and GraphQL and gRPC APIs for building financial systems.

Twisp is a cloud-native financial source of truth for companies building products that move, store, or account for money. It provides immutable ledgers, layered balances, transaction history, programmable transaction codes, velocity controls, reconciliation workflows, and payment processing building blocks.

Use Twisp when building ledgers, ACH processors, card processors, money movement workflows, FBO account systems, brokerage or position accounting systems, multi-currency accounting, real-time balance checks, fraud or spending controls, and systems that need to switch banks, processors, or partners without losing financial history.

Important product themes: customer-owned ledger data, provider portability, strong consistency, snapshot isolation, interactive transactions, materialized balances, fine-grained security policies, multi-tenancy, cloud and dedicated deployments, transparent usage-based pricing, and APIs designed for engineering teams.

API surfaces include GraphQL, gRPC, HTTPS requests, webhooks, and administrative console workflows. Twisp also supports protocol-oriented workflows including ACH ODFI/RDFI processing and card processing integrations.

## Documentation

- [Twisp documentation llms.txt](https://www.twisp.com/docs/llms.txt): Curated LLM-readable index for Twisp docs.

## Start Here

- [Twisp](https://www.twisp.com/docs/index.md): The accounting engine for financial products.
- [Introduction](https://www.twisp.com/docs/introduction.md): What is Twisp?
- [The Accounting Core](https://www.twisp.com/docs/accounting-core.md): An accounting engine for building products that work with money.
- [Twisp 101 Tutorial](https://www.twisp.com/docs/tutorials/twisp-101.md): Work through the steps in this tutorial to learn how to start building on the Twisp accounting core.
- [API Reference](https://www.twisp.com/docs/reference/api.md): Key components and concepts for interacting with the API.

## Core Concepts

- [Balances](https://www.twisp.com/docs/accounting-core/balances.md): With compute-on-write rollup calculations, balances always reflect the most up-to-date state of an account.
- [Chart of Accounts](https://www.twisp.com/docs/accounting-core/chart-of-accounts.md): The chart of accounts is the basis for creating balance sheets, P&L reports, and for understanding the balances for the customer and business entities your business services.
- [Encoded Transactions](https://www.twisp.com/docs/accounting-core/encoded-transactions.md): Design accounting logic with tran codes to create composable transaction types.
- [Layered Accounting](https://www.twisp.com/docs/accounting-core/layered-accounting.md): Layers help clarify the true state of funds in accounts.
- [Ledgers in Twisp](https://www.twisp.com/docs/accounting-core/ledgers-in-twisp.md): The accounting core is built upon a single source-of-truth ledger.
- [Computation Engine](https://www.twisp.com/docs/infrastructure/computation-engine.md): The computation infrastructure supports protocol workflows and an extensive financial calculation runtime via CEL.
- [Infrastructure](https://www.twisp.com/docs/infrastructure.md): Underneath the accounting core is a purpose-built ledger database and computation engine.
- [The Twisp Financial Ledger Database](https://www.twisp.com/docs/infrastructure/ledger-database.md): The ledger database is an immutable, append only data structure that provides strong gaurantees about the lineage of data.
- [Local Environment](https://www.twisp.com/docs/infrastructure/local-environment.md): The local environment helps streamline development and CICD integration testing with Twisp running on your own machine.
- [Security and Auth](https://www.twisp.com/docs/infrastructure/security-and-auth.md): Security policies control access to encrypted resources.
- [System Architecture](https://www.twisp.com/docs/infrastructure/system-architecture.md): Twisp is a purpose-built system that provides a mission-critical, high performance, core ledger for constructing and running financial products, empowering organizations to have complete control over their crucial financial data.
- [Transaction Isolation and Consistency](https://www.twisp.com/docs/infrastructure/transaction-isolation-and-consistency.md): Twisp provides snapshot isolation and strong consistency to ensure correctness and prevent anomalies in ledger systems.
- [A Short History of Twisp](https://www.twisp.com/docs/introduction/history.md): Why we did it.
- [DIY Ledgers are a Problem](https://www.twisp.com/docs/introduction/no-diy-ledger.md): We built a ledger database and accounting engine (so that you don't have to).
- [ACH Processor](https://www.twisp.com/docs/processors/ach.md): Understanding how the Twisp ACH processor works
- [Processors](https://www.twisp.com/docs/processors.md): Processing financial protocols and payment networks

## Guides

- [Branching Tenants and Managing Aliases](https://www.twisp.com/docs/guides/branching-and-aliasing.md): Create stable tenant aliases, copy configuration into branch tenants, and move an alias to a new branch.
- [Building Financial Systems with the Twisp Accounting Core](https://www.twisp.com/docs/guides/building-financial-systems.md): Design, implement, and optimize a financial system using Twisp. Covers everything from defining the financial services to be provided, designing accounts and transactions, ensuring security and compliance, integrating with other...
- [Effective Balances](https://www.twisp.com/docs/guides/effective-balances.md): Roll up balances by the effective date of activity to answer point-in-time, statement, and income-statement questions — even when transactions arrive late or are backdated.
- [Handling ACH Returns](https://www.twisp.com/docs/guides/handling-ach-returns.md): Process and manage ACH returns effectively
- [Guides](https://www.twisp.com/docs/guides.md): Use these how-to guides to build solutions for real-world financial systems using Twisp.
- [Modeling Banking on Twisp](https://www.twisp.com/docs/guides/neobanking-guide.md): Design and Implement bank-like core accounting on Twisp.
- [Position-Based Accounting for Securities Trading with Twisp](https://www.twisp.com/docs/guides/position-accounting.md): Learn how to set up position-based accounting for securities trading using Twisp in this comprehensive guide. From designing a suitable chart of accounts and defining transaction codes, to posting transactions for trading activities and...
- [Processing ACH Payments](https://www.twisp.com/docs/guides/processing-ach-payments.md): Process production ACH payments efficiently
- [Reconciling ACH Files](https://www.twisp.com/docs/guides/reconciling-ach-files.md): Validate and reconcile ACH file processing

## Tutorials

- [Tutorials](https://www.twisp.com/docs/tutorials.md): These tutorials cover the skills needed to work with the Twisp accounting core with simple, step-by-step instructions and relevant examples.
- [Setting Up Accounts](https://www.twisp.com/docs/tutorials/setting-up-accounts.md): In this tutorial, we will learn how to manage accounts using the GraphQL API.
- [Posting Transactions](https://www.twisp.com/docs/tutorials/posting-transactions.md): In this tutorial, we will learn how to post transactions using the GraphQL API.
- [Pulling Balances](https://www.twisp.com/docs/tutorials/pulling-balances.md): In this tutorial, we will learn how to query account balances using the GraphQL API.
- [Organizing with Account Sets](https://www.twisp.com/docs/tutorials/organizing-with-account-sets.md): In this tutorial, we'll explore how to use account sets to organize your chart of accounts.
- [Building Tran Codes](https://www.twisp.com/docs/tutorials/building-tran-codes.md): In this tutorial, we will learn how to manage transaction codes using the GraphQL API.
- [Working with Journals](https://www.twisp.com/docs/tutorials/working-with-journals.md): In this tutorial, we will learn how to add additional journals to handle a multi-journal ledger system.
- [Making API Requests with cURL](https://www.twisp.com/docs/tutorials/api/making-api-requests-with-curl.md): In this tutorial, we will learn how to make requests against the Twisp GraphQL API using the curl command line tool.
- [Querying Paginated Fields](https://www.twisp.com/docs/tutorials/api/querying-paginated-fields.md): In this tutorial, we will learn to handle cursor-paginated fields in the GraphQL schema.

## Reference

- [Reference](https://www.twisp.com/docs/reference.md): Definitions of all components in the Twisp Accounting Core and GraphQL API.
- [GraphQL API Reference](https://www.twisp.com/docs/reference/graphql.md): Documentation for the Twisp GraphQL API.
- [Ledger Reference](https://www.twisp.com/docs/reference/ledger.md): A Twisp ledger is composed of accounts, account sets, balances, entries, journals, transactions, and tran codes.
- [ACH Reference](https://www.twisp.com/docs/reference/ach.md): The Twisp ACH processor handles configuration, file operations, ODFI origination, and RDFI receiving operations.
- [CEL Reference](https://www.twisp.com/docs/reference/cel.md): Embedded computation with the common expression language runtime.

## Optional

- [Complete documentation corpus](https://www.twisp.com/docs/llms-full.txt): All published documentation in one large file.
- [Concepts and architecture corpus](https://www.twisp.com/docs/llms-concepts.txt): Introduction, Accounting Core, processors, and infrastructure documentation in one file.
- [Guides corpus](https://www.twisp.com/docs/llms-guides.txt): Published solution guides for building financial systems with Twisp.
- [Tutorials corpus](https://www.twisp.com/docs/llms-tutorials.txt): All published step-by-step Twisp tutorials in one file.
- [Reference corpus](https://www.twisp.com/docs/llms-reference.txt): Ledger, API, GraphQL, ACH, and CEL reference documentation in one file.