Avalanche Indexer

A Go monorepo for indexing and processing Avalanche blockchain data. It includes reusable packages and runnable services under cmd/.

Monorepo layout

• cmd/ — runnable services (e.g., blockfetcher)
• pkg/ — shared libraries (e.g., slidingwindow)
• Dockerfile — multi-binary image build that can run any service via APP
• Makefile — build, test, lint targets

Requirements

• Go 1.24+
• Make
• Docker (optional, for container builds)

Build

Build all services:

make build-all

Build a specific service:

APP=blockfetcher make build-app

Artifacts are placed in bin/.

Test and lint

make unit-test
make lint

Docker

This repo uses a single multi-binary Docker image. At runtime, select which binary to run with the APP environment variable.

Build all services into one image:

docker build -t indexer:latest .

Optionally, build a single service for faster builds:

docker build -t indexer:blockfetcher --build-arg APP=blockfetcher .

Run a service (example: blockfetcher):

bin/blockfetcher run \
  --evm-chain-id 43114 \
  --bc-id "11111111111111111111111111111111LpoYY" \
  --rpc-url wss://api.avax-test.network/ext/bc/C/ws \
  --start-height 0 \
  --concurrency 16 \
  --backfill-priority 4 \
  --blocks-ch-capacity 200 \
  --max-failures 5 \
  --kafka-brokers localhost:9092 \
  --kafka-topic blocks \
  --verbose

See each service’s README for its full flag/env reference.

Services

• blockfetcher — fetches blocks from a Coreth-compatible RPC and processes them via a sliding window.
  • See cmd/blockfetcher/README.md

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Local Development Setup

This project includes a Docker Compose configuration for local development with:

• Apache Kafka (KRaft mode, no Zookeeper)
• Provectus Kafka UI
• ClickHouse (with Tabix UI)

Quick Start

# Start all services
docker compose up -d

# View logs
docker compose logs -f

# Stop services
docker compose down

# Stop and remove volumes
docker compose down -v

Services & Ports

Service	Port	Description
Kafka	9092	External client access (from host)
Kafka	9093	Internal access (container-to-container)
Kafka UI	8080	Web UI for Kafka management
ClickHouse	8123	HTTP interface
ClickHouse	9000	Native protocol
Tabix	8082	ClickHouse web UI

Connecting from Host Applications

# Kafka bootstrap server
localhost:9092

# Kafka UI
http://localhost:8080

# ClickHouse
http://localhost:8123

# Tabix (ClickHouse UI)
http://localhost:8082

Connecting from Other Docker Containers

Add your container to the kafka-network network and use:

# Kafka bootstrap server
kafka:9093

# ClickHouse
clickhouse:8123

Kafka UI Features

The Kafka UI is pre-configured with:

• Cluster: local-kafka pointing to the local Kafka broker
• Dynamic Config: Enabled (DYNAMIC_CONFIG_ENABLED=true) — allows adding/editing clusters via the UI

Access the UI at http://localhost:8080 to:

• View and create topics
• Browse messages
• Manage consumer groups

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Examples

Block Fetcher

Start ingestion from specific block (no checkpoint):

# spin up containers (checkpoints table will be created)
docker-compose up -d

# build applications
make build-all

# run block fetcher for Fuji testnet starting from block 48662238 using default checkpoints table
./bin/blockfetcher run -r wss://api.avax-test.network/ext/bc/C/ws -C 43113 -b 9 -B 5 -c 10 -s 48662238

The checkpoints can be checked using UI at http://localhost:8082 To login use these values:

name: dev (can be any other name)
host: http://127.0.0.1:8123
login: default

Select default in ClickHouse Server tab (on the left).

checkpoint records can be added manually:

INSERT INTO default.checkpoints (chain_id, lowest_unprocessed_block, timestamp) 
VALUES (43114, 48662238, 1767903034)

Start ingestion from checkpoint:

# run block fetcher for Fuji testnet starting from latest un-ingested 
# block in default checkpoints table
./bin/blockfetcher run -r wss://api.avax-test.network/ext/bc/C/ws -C 43113 -b 9 -B 5 -c 10

Contributing

• Open an issue or pull request
• Run make unit-test and make lint before submitting

License

See LICENSE.