Daimo is a universal cash app

Today, we run on USDC on Base. Cross-chain transfers and more coming soon.

No seed phrases. Keys are generated in your phone's secure enclave and never leave. You can add multiple devices and create Passkey backups to secure your account. Under the hood, it's a ERC-4337 contract wallet.

The mission is to make an excellent experience. Sound assets, secure cryptography, your coins in your control.

FAQ

• How do Daimo accounts work?

  Daimo accounts are Ethereum accounts.

  Under the hood, they're a new and much-improved type called an ERC-4337 contract account. Each device you add to your account stores a secret key. When you send money, your phone first authenticates you with FaceID or similar, then cryptographically signs the transaction using that key.

  Daimo is non-custodial. Your keys, your coins.

  Daimo offers stronger security than traditional wallets. Keys live in dedicated hardware made for storing secrets, such as Secure Enclave on iPhone, and never leave your device.

• Which stablecoin does Daimo use?

  Daimo runs on USDC, a high-quality stablecoin issued by Circle.

  Stablecoins are cryptocurrencies designed to maintain a stable value. Many are pegged to the dollar, so that one coin is worth $1. Circle is a US-based licensed money transmitter partnered with Coinbase. USDC is one of the largest and most liquid onchain dollar equivalents. Learn more on Bluechip.

• Which blockchain does it run on?

  Daimo uses Base, an Ethereum rollup.

  Rollups support near-instant transactions that cost a few cents each. By contrast, transactions on the underlying Ethereum chain (layer 1 or L1) take about 10 times as long and cost a few dollars each. Rollups accomplish this by bundling many transactions into a single L1 transaction. They inherit the strong guarantees of Ethereum: like L1, Base is reliable and secure, and works worldwide. Learn more on L2Beat.

• Can I send other coins like USDT, or use other chains like Polygon?

  Not yet. We plan to support payments in other stablecoins and on other chains soon.

• Who can see my Daimo transactions?

  Currently, all Ethereum transactions are generally public, including Daimo transactions. We plan to add private payments as the infrastructure and support for them matures.

• Is Daimo open source?

  Yes, Daimo is and will always be open-source under GPLv3. We're here to collaborate. We want to make self-custody fast, safe, and easy. See more on our Github.

Security

Audits

Past audits of the Daimo codebase can be found in the audits folder:

• Coming soon: OpenZeppelin audit 2024 Aug
• Veridise audit 2023 Nov: WebAuthn verifier
• Veridise audit 2023 Oct: P-256 verifier
• Veridise audit 2023 Oct: Daimo

Bug Bounty Program

Daimo hosts a bug bounty program on Immunefi. Learn more on SECURITY.md.

Development

Daimo is under active development. Now in App Store and Play Store with an invite code. Coming soon: desktop app, no invite code, cross-chain support.

Architecture

READMEs for each app and package.

• apps/daimo-mobile mobile app. Typescript + Expo
• apps/daimo-web web app, including deep links. Typescript + NextJS
• packages/contract contracts, Solidity + Forge
• packages/daimo-api API, including indexer. Typescript + Node
• packages/daimo-common data models common to apps and API. Typescript
• packages/daimo-expo-enclave hardware enclave interface. Typescript, Kotlin, Swift + Expo native module
• packages/daimo-userop account abstraction interface. Typescript

Dev quickstart

Clone the repo, loading submodules.

git clone [email protected]:daimo-eth/daimo --recurse-submodules

Build the app.

node --version # ensure you have node 21+
npm i
npm run build

Run the iPhone Simulator in XCode. (If you're not on a Mac, see the Android quick start below.) Get the latest simulator build from Expo; message us if you need access. Drag-drop the build into the simulator to install.

Copy the example .env file to use the remote, hosted API.

cd apps/daimo-mobile
cp .env.example .env

Finally, run the app in the simulator.

npm run dev

Use invite code testnet. Once you create an account, you should automatically get some testnet USDC from the faucet.

Expo apps come in two layers: a native layer and a React Native (Typescript) layer. Whenever you add a native module or update @daimo/expo-enclave, you must rebuild the native app. For details, see apps/daimo-mobile.

Dev quickstart: Android

• Ensure you have the correct Java version. Version 20 doesn't work, Java 17 works.
• You need to ANDROID_HOME to the local Android SDK.
• Install Android Studio, and create an emulator.
• Download latest Android internal distribution build from Expo, and install it in the emulator.

All other instructions are the same as above. After npm run dev, type a to open the Android simulator. You should now have both side-by-side. See the mobile package.json for details.

Dev quickstart: contracts

Install Foundry.

curl -L https://foundry.paradigm.xyz | bash
# Reload your terminal, then run:
foundryup

Build the contracts.

forge build

For commands to run tests and recompute code coverage, see ci.yml.

Dev quickstart: API

daimo-mobile and daimo-web both rely on daimo-api.

By default:

• daimo-mobile runs the Expo incremental build server on localhost:8080
• daimo-web runs the web app, including fallback deeplinks, on localhost:3001
• daimo-api runs the TRPC API on localhost:3000

You'll need to either use the hosted Daimo API or run one locally.

To run the API locally, fill in .env. Message us if you need help.

You can run Postgres in the background locally using the Mac Postgres app.

Once you're running the API locally, you can run the full stack self-contained.

# First tab
cd packages/daimo-api && npm run dev
# Second tab
cd apps/daimo-mobile && npm run dev
# Third tab
cd apps/daimo-web && npm run dev

Dev quickstart: Maestro

daimo-mobile runs end to end tests with Maestro.

To write or run a test locally, first obtain a Expo build labelled with profile maestro here.

Then, with Maestro installed, you can simply run maestro test <test file name> to run the test. Example: maestro test .maestro/onboardAndRemove.yaml.

In the cloud, these tests are run on the master branch using the maestro-ci workflow in Maestro cloud.

DB diagnostics

Indexer caught up?

SELECT * FROM index.daimo_index;

Largest Postgres DB tables, disk usage:

SELECT
  table_schema,
  table_name,
  pg_size_pretty(pg_total_relation_size(c.oid)) AS total_size
FROM
  information_schema.tables t
JOIN
  pg_class c ON c.relname = t.table_name
WHERE table_type = 'BASE TABLE'
ORDER BY pg_total_relation_size(c.oid) DESC
LIMIT 20;

Largest tables, approximate row count:

SELECT
  (SELECT nspname FROM pg_namespace WHERE oid=relnamespace) as r_schema,
  relname as r_name,
  reltuples as approx_num_rows,
  (relpages * 8) / 1024 as approx_disk_mb
FROM pg_class
WHERE reltuples > 0
ORDER BY reltuples DESC;