Hedera VSCode Extension

Your complete toolkit for building on Hedera - from smart contracts to SDK development, all within VS Code.

What is this?

The Hedera VSCode Extension brings the entire Hedera development experience into your editor. Whether you're writing smart contracts, integrating SDKs across 8 languages, or exploring the Mirror Node API - it's all here, without switching contexts.

Perfect for:

Smart contract developers using Hardhat or Foundry
SDK developers working with Hedera's multi-language SDKs
Teams building dApps that need quick network testing
Anyone tired of jumping between tools to deploy, debug, and verify

🚀 Project Setup & Templates

One-click project creation from official Hedera templates (Hardhat, Foundry, React DApp, Upgradeable Contracts)
Instant scaffolding with working examples, latest dependencies, and network configs
Auto-detection of existing Hardhat/Foundry projects

💼 Account & Network Management

Secure account storage with ECDSA/ED25519 support
Quick network switching (testnet, mainnet, previewnet, custom)
Live balance refresh and EVM address display
One-click operator account setup
Auto-sync to .env files for seamless CI/CD

📦 Smart Contract Development

Compile contracts directly from the sidebar (Hardhat/Foundry detection)
Deploy with one click - choose network, customize gas, track deployments
Verify on HashScan automatically or manually
Deployment history with timestamps, networks, and direct explorer links
Gas estimation with inline CodeLens (see estimated gas above functions)

💻 SDK Development Support (8 Languages!)

Rich autocomplete for JavaScript, TypeScript, Java, Go, Rust, C++, Swift, Python
Hover documentation - see SDK docs by hovering over classes and methods
Code snippets - hedera-* templates for accounts, tokens, contracts, topics
Direct links to official Hedera documentation

🔍 Debugging & Inspection

Contract Debug Panel - compile, test read/write functions, see gas estimates
ABI Encode/Decode - convert between calldata and readable parameters
Transaction inspection - full receipts with status, gas used, error details
Dedicated debug output with timestamps and formatted results
Smart error interpretation (no more cryptic blockchain errors)

🌐 Mirror Node Explorer

Visual API builder - construct REST queries from official OpenAPI spec
Instant code generation - copy as cURL, Fetch, or Node.js snippets
Query accounts, transactions, tokens, topics, and contracts
Test endpoints and see formatted JSON responses

⚙️ Developer Experience

Inline links - hover 0.0.123 → jump to HashScan or copy
Hedera-specific diagnostics - highlights unsupported Solidity patterns (selfdestruct, delegatecall)
MCP integration - preconfigured servers for AI tools (Cursor, Windsurf, Claude)
Syntax highlighting and semantic tokens for Solidity/Vyper

📦 Installation

From VS Code Marketplace

Open VS Code
Go to Extensions (Ctrl+Shift+X / Cmd+Shift+X)
Search for "Hedera"
Click Install

Requirements

VS Code 1.85.0 or higher
Node.js 16+ (for project templates and compilation)
Git (for cloning templates)

🚀 Quick Start

1. Create Your First Project

Cmd/Ctrl+Shift+P → "Hedera: Create New Project"

Choose a template (Hardhat, Foundry, React DApp, or Upgradeable)
Extension clones official Hedera repo and installs dependencies
Open the new project and you're ready to code

2. Import or Create an Account

From the sidebar:

Click "+" in Hedera Accounts view
Choose "Import Account" (paste account ID + private key)
Or "Create Account" to generate new keys
Set as operator for signing transactions

3. Deploy Your First Contract

From the Smart Contracts view:

Expand your project in the sidebar
Find your contract → Click Deploy button (cloud upload icon)
Select network (testnet recommended)
Review gas settings → Deploy
Extension logs transaction, saves deployment, and links to HashScan

4. Test with Debug Panel

From the Smart Contracts view:

Click Debug Panel button (beaker icon) on any contract
Choose an action:
- Compile - run Hardhat/Foundry compiler
- Read function - test view/pure functions with gas estimates
- Write function - send transactions with dynamic gas calculation
- View logs - see formatted results in debug output

💡 Tip: All contract actions (Deploy, Compile, Verify, Debug) appear as inline buttons in the Smart Contracts sidebar. No need to right-click!

📖 Common Workflows

🏗️ Create a Hardhat Project and Deploy

Hedera: Create New Project → Select "Hardhat Official Example"
Import your testnet account (or create new one)
In Hedera Accounts view, right-click account → "Set as Operator"
Open "Smart Contracts" view in sidebar
Expand your project → Find contract → Click Deploy button
Choose testnet → Confirm → See deployment in HashScan

🔍 Debug a Contract Function

Open "Smart Contracts" view in sidebar
Find your contract → Click Debug Panel button (beaker icon)
Select "Read function (call)" from the menu
Choose function from ABI
Input arguments → Extension shows gas estimate and return value
Copy result or view in debug output channel

🌐 Query Mirror Node API

Hedera: Build Mirror Node Endpoint
Select network (testnet/mainnet)
Choose API endpoint (e.g., /api/v1/accounts/{id})
Fill in parameters
Click "Send Request" → See JSON response
Copy as cURL, Fetch, or Node.js code

💬 Use SDK Autocomplete

Create a .js file in your project
Start typing: Client. → Extension shows forTestnet(), forMainnet(), setOperator()
Hover over any SDK class → See full documentation with examples
Use snippets: type hedera-transfer → Get complete transfer transaction template

✅ Verify Contract on HashScan

After deployment, click "Verify on HashScan" prompt
Or in Smart Contracts view, expand contract → Click Verify button (checkmark icon) on deployment
Extension auto-fills constructor args, compiler version
Submit → See verification status
Contract source now visible on HashScan

🎨 Screenshots

Account Management Panel

Manage Hedera accounts, view balances, and switch networks from the sidebar.

Account Panel

Smart Contracts View

Deploy, compile, and debug contracts with inline action buttons. Track deployment history.

Contracts Panel

SDK Hover Documentation

Hover over SDK classes and methods to see rich documentation with code examples across all 8 supported languages.

Hover Documentation

Gas Estimation CodeLens

Inline gas estimates appear above Solidity functions with color-coded indicators (🟢 low, 🟡 medium, 🔴 high).

Gas Estimation

Mirror Node API Explorer

Build REST queries from OpenAPI spec, test endpoints, and generate code snippets for cURL, Fetch, or Node.js.


Welcome screen	Endpoint builder with parameters	Query results with code generation

Network Configuration

Add custom networks via Hedera: Manage Networks:

Node URL (JSON-RPC endpoint)
Mirror Node URL (REST API)
Chain ID
Network name

❓ FAQ & Troubleshooting

Extension not detecting my contracts?

Ensure you have hardhat.config.js or foundry.toml in your workspace
Run Hedera: Refresh Contracts from command palette
Check that contracts are compiled (artifacts/ or out/ exists)

How do I add a custom network?

Click settings icon in "Hedera Accounts" sidebar
Select "Manage Networks"
Add JSON-RPC URL, Mirror Node URL, and Chain ID
Network appears in switch dropdown

Is my private key secure?

Keys stored in VSCode's secure storage (system keychain)
Never logged or transmitted except for signing transactions
Disable .env sync if you don't want keys in files
Use .gitignore to exclude .env from version control

Gas estimation not working?

Ensure contracts are compiled first
Check that you have valid operator account set
Try disabling autoEstimate if it's slow
Click "Refresh Gas Estimates" to recalculate

Deploy fails with "account not found"?

Verify account exists on selected network (testnet vs mainnet)
Check account has sufficient HBAR balance
Confirm private key matches the account ID

Where can I get help?

🤝 Contributing

We welcome contributions! Here's how to set up for development:

Developer Setup

Clone the repository

git clone https://github.com/tolgayayci/hedera-vscode.git
cd hedera-vscode

Install dependencies

npm install

Compile TypeScript

npm run compile

Launch Extension Development Host

Press F5 in VS Code
New window opens with extension loaded
Make changes → Reload window (Ctrl+R) to test

Pull Request Process

Create a feature branch
Make your changes
Run linter: npm run lint
Run tests: npm test (if applicable)
Commit with clear messages
Open PR with description of changes

📚 Additional Resources

Hedera Documentation - Official Hedera developer docs
SDK Documentation - Multi-language SDK guides
HashScan Explorer - Network explorer
Hedera Portal - Create testnet accounts

📄 License

MIT License - see LICENSE file for details.

🙏 Acknowledgments

Built with ❤️ for the Hedera developer community.

Special thanks to:

Hedera team for SDK and infrastructure support
VSCode extension API contributors
Community feedback and testing

Ready to build on Hedera? Install the extension and create your first project in minutes! 🚀

Hedera VSCode

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