Question 1

How do I fork a Polkadot chain for local development?

Accepted Answer

Clone the repository, install dependencies, download the Polkadot binary and WASM blob from GitHub releases, place them in the data folder, set HTTP_RPC_ENDPOINT to a Polkadot node, and run npm start to generate the genesis file.

Question 2

What's the difference between Fork off Substrate and running a standard Substrate node?

Accepted Answer

Fork off Substrate creates a new genesis file with the live state, allowing isolated testing, whereas a standard node syncs from genesis or existing chain data without forking.

Question 3

Can I fork a chain from a specific block height, not just the latest?

Accepted Answer

Yes, you can specify the block height by modifying the RPC queries or using a local node synced to that block, though the README doesn't explicitly detail this; it assumes current state.

Question 4

How to use Docker to run Fork off Substrate?

Accepted Answer

Build the Docker image with docker build, then run it with environment variables like HTTP_RPC_ENDPOINT and mount the binary using -v flag, as shown in the Using Docker section.

Question 5

What happens if the RPC endpoint disconnects during forking?

Accepted Answer

The process will likely fail or produce an incomplete genesis file, so it's recommended to use a reliable local node or stable external endpoint.

Question 6

Is there a way to automate the setup of binary and WASM files?

Accepted Answer

The README doesn't provide automation; users must manually obtain and place these files, which can be scripted externally but isn't built-in.

Question 7

Fork off Substrate vs using Polkadot's built-in testnet features – which is better?

Accepted Answer

Fork off Substrate is better for testing against exact live state, while Polkadot's testnets are separate networks with different states; choose based on whether you need realism or convenience.

Fork Off Substrate

What is Fork Off Substrate?

Overview

Use Cases

Best For

Related Projects

Found a gem we're missing?

Not Ideal For

Pros & Cons

Pros

Cons

Frequently Asked Questions