celestia-core

celestia-core is a fork of cometbft/cometbft, an implementation of the Tendermint protocol, with the following changes:

1. Early adoption of the ABCI++ methods: PrepareProposal and ProcessProposal because they haven't yet landed in a CometBFT release.
2. Modifications to how DataHash in the block header is determined. In CometBFT, DataHash is based on the transactions included in a block. In Celestia, block data (including transactions) are erasure coded into a data square to enable data availability sampling. In order for the header to contain a commitment to this data square, DataHash was modified to be the Merkle root of the row and column roots of the erasure coded data square. See ADR 008 for the motivation or celestia-app/pkg/da/data_availability_header.go for the implementation. Note on the implementation: celestia-app computes the hash in prepare_proposal and returns it to CometBFT via blockData.Hash so a modification to celestia-core isn't strictly necessary but comments were added.
3. The GRPC server exposed by CometBFT was modified to expose Celestia-specific APIs:
   • BlockAPI
   • BlobstreamAPI

See ./docs/celestia-architecture for architecture decision records (ADRs) on Celestia modifications.

Diagram

                ^  +-------------------------------+  ^
                |  |                               |  |
                |  |  State-machine = Application  |  |
                |  |                               |  |   celestia-app (built with Cosmos SDK)
                |  |            ^      +           |  |
                |  +----------- | ABCI | ----------+  v
Celestia        |  |            +      v           |  ^
validator or    |  |                               |  |
full consensus  |  |           Consensus           |  |
node            |  |                               |  |
                |  +-------------------------------+  |   celestia-core (fork of CometBFT)
                |  |                               |  |
                |  |           Networking          |  |
                |  |                               |  |
                v  +-------------------------------+  v

Install

See https://github.com/celestiaorg/celestia-app#install

Usage

See https://github.com/celestiaorg/celestia-app#usage

Contributing

This repo intends on preserving the minimal possible diff with cometbft/cometbft to make fetching upstream changes easy. If the proposed contribution is

• specific to Celestia: consider if celestia-app is a better target

• not specific to Celestia: consider making the contribution upstream in CometBFT

• Install Go 1.23.6+

• Fork this repo
• Clone your fork
• Find an issue to work on (see good first issues)
• Work on a change in a branch on your fork
• When your change is ready, push your branch and create a PR that targets this repo

Helpful Commands

# Build a new CometBFT binary and output to build/comet
make build

# Install CometBFT binary
make install

# Run tests
make test

# If you modified any protobuf definitions in a `*.proto` file then
# you may need to lint, format, and generate updated `*.pb.go` files
make proto-lint
make proto-format
make proto-gen

Branches

• main is the canonical branch for development. Most PRs should target this branch and optionally be backported to a release branch.
• v0.38.x-celestia was based on CometBFT v0.38.x. Releases from this branch look like v1.54.1-tm-v0.38.17 and are used by celestia-app v4.x.
• v0.34.x-celestia was based on CometBFT v0.34.x. Releases from this branch look like v1.52.1-tm-v0.34.35 and are used by celestia-app v3.x.

Releases

Previous releases are formatted: v<CELESTIA_CORE_VERSION>-tm-v<COMETBFT_VERSION>. For example: v1.4.0-tm-v0.34.20 is celestia-core version 1.4.0 based on CometBFT 0.34.20. CELESTIA_CORE_VERSION strives to adhere to Semantic Versioning.

Note: future releases from the main branch may be released as v0.39.x without the TENDERMINT_CORE_VERSION suffix because CometBFT v0.39.x was not released.