synpress
Synpress is an end-to-end testing framework built on Cypress and Playwright that adds native support for MetaMask wallet interactions and blockchain operations. It enables developers to test Web3 dApps by automating wallet setup, caching browser state, and supporting both sequential and parallel test execution.
Key facts
Objective fields from the source. Values we can't verify are shown as “Unknown” rather than guessed.
| Field | Value |
|---|---|
| Repository | synpress-io/synpress |
| Owner | synpress-io |
| Primary language | TypeScript |
| License | MIT — OSI-approved |
| Stars | 888 |
| Forks | 219 |
| Open issues | 125 |
| Latest release | 3.7.3 (2024-05-30) |
| Last updated | 2026-01-10 |
| Source | https://github.com/synpress-io/synpress |
What synpress is
TypeScript-based E2E testing library layering wallet automation and blockchain-specific utilities over Cypress/Playwright. Provides MetaMask integration, browser state caching for performance, local Anvil node support, and a wallet-agnostic core architecture designed for multi-chain dApp testing.
Get the synpress source
Clone the repository and explore it locally.
git clone https://github.com/synpress-io/synpress.gitcd synpress# follow the project's README for install & configurationNeed it deployed, integrated, or customized instead? DEV.co ships production installs.
Best use cases
Implementation considerations
- Browser rendering required: CI/CD pipelines must support Docker containers or native browser environments; headless mode may not support all wallet UI interactions.
- MetaMask extension version compatibility: wallet behavior and UI can change across releases; tests may require maintenance when MetaMask updates.
- Test isolation and state management: caching browser state speeds up execution but risks cross-test contamination; careful setup/teardown discipline is essential.
- Local node integration: Anvil setup for deterministic environments is optional but recommended; requires Node.js and Ethereum tooling knowledge.
- TypeScript adoption: while not mandatory, TypeScript is recommended for type safety; JavaScript projects will have less IDE support and catch fewer errors at development time.
When to avoid it — and what to weigh
- Non-wallet or traditional Web2 dApp testing — If your dApp does not require wallet interaction or blockchain operations, a general-purpose E2E framework (plain Cypress/Playwright) is simpler and more lightweight.
- Wallet platforms other than MetaMask without custom adapter — Synpress is optimized for MetaMask; testing against WalletConnect, Ledger, or other wallets is not built-in and requires custom integration work.
- Production-grade audit or compliance testing — E2E testing frameworks are not substitutes for smart contract audits, penetration testing, or formal security verification required for regulated financial products.
- Minimal infrastructure or headless-only environments — Synpress/Cypress/Playwright require visual browser rendering; CI/CD pipelines must support browser containers, which may be complex in restricted or air-gapped networks.
License & commercial use
Synpress is released under the MIT License, a permissive OSI-approved open-source license. MIT grants rights to use, modify, and distribute the software with minimal restrictions, provided the original license and copyright notice are retained.
MIT License permits commercial use without explicit royalty or licensing fees. However, commercial use of Synpress should account for: (1) any dependencies Synpress bundles that may have different license terms (requires review of package.json); (2) the warranty disclaimer in MIT (no liability for failures); (3) the requirement to retain and distribute the MIT notice in any derivative distribution. For regulated financial or critical infrastructure use, legal review is advised to confirm compliance with your broader licensing strategy.
DEV.co evaluation signals
Editorial assessment — not user reviews. Directional, with an explicit confidence level.
| Signal | Assessment |
|---|---|
| Maintenance | Active |
| Documentation | Adequate |
| License clarity | Clear |
| Deployment complexity | Moderate |
| DEV.co fit | Good |
| Assessment confidence | High |
Security considerations for Synpress test environments: (1) MetaMask integration requires injecting a browser extension into automation contexts—ensure test infrastructure is isolated and not exposed to untrusted test code; (2) Local Anvil nodes may expose chain state or test wallets if not properly isolated; (3) browser state caching may retain sensitive data (cookies, tokens) across tests—implement state cleanup; (4) no explicit security audit or disclosure policy mentioned in provided data; (5) tests execute user-facing wallet interactions—verify that test accounts and private keys are never stored in version control or logs. Synpress itself is not a security product and does not provide wallet or network security guarantees.
Alternatives to consider
Hardhat + ethers.js + Mocha/Jest
Lower-level, contract-focused testing; no GUI automation. Better for smart contract unit/integration tests but lacks dApp UI testing and wallet simulation.
Foundry (Forge) + Solidity tests
Solidity-native testing framework for contract-level validation. Faster for pure contract logic but does not test frontend or wallet interactions; not a replacement for E2E.
Playwright/Cypress alone + custom wallet automation
More control and no framework overhead, but requires building wallet interaction logic from scratch; time-consuming and error-prone for complex dApp workflows.
Build on synpress with DEV.co software developers
Synpress simplifies Web3 E2E testing with MetaMask integration and blazing-fast parallel execution. Explore our development services to build and test robust blockchain applications.
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synpress FAQ
Does Synpress work with wallets other than MetaMask?
Can I run tests in parallel with Synpress?
Do I need Docker for Synpress?
What is the learning curve for teams new to Cypress/Playwright?
Custom software development services
Adopting synpress is usually one piece of a larger software development effort. As a software development agency, DEV.co provides software development services and web development expertise — pairing senior software developers and web developers with your team to design, build, and operate open-source testing software in production.
Ready to test your dApp reliably?
Synpress simplifies Web3 E2E testing with MetaMask integration and blazing-fast parallel execution. Explore our development services to build and test robust blockchain applications.