⚡ NextIndex: Solana Program Indexer

A high-performance, containerized Solana program indexer built with Bun, ElysiaJS, and Drizzle ORM. It fetches transactions via RPC, decodes instruction data using Anchor IDL, stores them in a MySQL database, and exposes them through a beautifully documented REST API.

Built for the Superteam Ukraine Bounty.

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🏗 Architecture Overview

• Core Engine: A polling background worker (SolanaIndexer) that continuously fetches new transactions for a specific PROGRAM_ID.
• Smart Decoding: Utilizes @coral-xyz/anchor (BorshInstructionCoder) to parse raw base58 bytes into human-readable JSON. Supports both local program_idl.json and dynamic on-chain IDL fetching.
• Rate-Limit Resilient: Implements strategic micro-delays and single-fetching mechanisms to bypass public RPC 429 Too Many Requests and free-tier 403 Forbidden batch errors.
• Database: MySQL managed by Drizzle ORM for strict typing and fast queries.
• REST API: Powered by ElysiaJS and Bun for maximum speed, featuring auto-generated Swagger (Scalar) documentation.

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🚀 Setup & Launch

The entire infrastructure (Database + Indexer + API) is dockerized and runs with a single command.

1. Prerequisites

• Docker & Docker Compose installed.

2. Environment Variables

Clone the repository and create a .env file in the root directory. Fill in the variables as shown below:

RPC_URL=https://api.mainnet-beta.solana.com
PROGRAM_ID=whirLbMiicVdio4qvUfM5KAg6Ct8VwpYzGff3uctyCc  # Example: Orca Whirlpools
IDL_ADDRESS=whirLbMiicVdio4qvUfM5KAg6Ct8VwpYzGff3uctyCc

💡 Recommended: Use a Helius RPC URL instead of the public endpoint — it's significantly faster, more stable, and avoids rate-limiting during indexing. Free tier is more than enough to get started.

3. Start the Application

Run the following command to build the image, start MySQL, run Drizzle migrations, and boot the API:

docker compose up --build -d

• The indexer will start logging in the background.
• Swagger UI docs will be available at: http://localhost:3000/api/swagger

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🌐 API Examples

Get a transaction by signature

curl -X GET "http://localhost:3000/api/transactions/5ojHZrUk6ye44uMXAtyHAAipAan7P3woqt2wp95T1u7ykfoe3y7Zy5AHUaoV2HfeiBqrWPZvLsWnM3Q5JRPZhRvZ"

Get a list of transactions (with filters)

# Get 5 latest 'swap' instructions
curl -X GET "http://localhost:3000/api/transactions?instruction_name=swap&limit=5"

# Filter by a specific signer
curl -X GET "http://localhost:3000/api/transactions?signer=YOUR_WALLET_ADDRESS"

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🧠 Key Technical Decisions & Trade-offs

Decision	Rationale
Bun + Elysia over Node.js + Express	Significantly better performance, built-in TypeScript support, and elegant Swagger integration.
Drizzle ORM over Prisma	Closer-to-SQL syntax, no heavy Rust engine — keeps the Docker image lighter and migrations faster.
Single-fetching over Batching	getParsedTransactions gets blocked by free-tier RPCs (Helius, etc.). Iterating signatures individually with a 150ms delay is slower for historical backfill but 100% reliable and crash-proof.