Docs

Deep notes on Robinhood Chain nodes — what the public docs say, what we ran for dogecoin but on robinhood / rhDOGE, and how the pieces fit together. Source of truth for operators: Run a Robinhood Chain full node.

What Robinhood Chain is

Robinhood Chain is an Arbitrum Chain running Arbitrum Nitro. It currently runs ArbOS 61. Like other Nitro-based L2s, it posts its data to Ethereum L1 — so a Robinhood Chain node is not a standalone L1; it depends on a healthy Ethereum view (execution + beacon) to finish syncing and stay honest about blobs.

If you only need JSON-RPC and do not want to operate infrastructure, Robinhood documents public endpoints (and provider options like Alchemy). We still spun our own full node so rhDOGE could live on rails we control.

• Public Mainnet RPC: https://rpc.mainnet.chain.robinhood.com
• Alchemy pattern: https://robinhood-mainnet.g.alchemy.com/v2/{API_KEY}

Why run your own node (and what we did)

The official docs are blunt: running a node is time consuming, resource intensive, and potentially costly. If you do not already know why you need one, you probably do not.

Our reason was product-shaped: Robinhood Chain lets creators run nodes and build. We used that permission to put Dogecoin on Robinhood Chain — high throughput, near-zero user cost on our explorer story — as the punchline to Vlad Tenev’s 2022 “currency of the internet” thread.

Architecture overview

A useful mental model:

• Ethereum L1 execution RPC — parent-chain connection for L1 state / posting surface
• Ethereum L1 beacon (consensus) — required to read blob data (common sync failure point)
• Nitro node — offchainlabs/nitro-node with Robinhood chain-info (+ mainnet genesis)
• Optional sequencer feed — websocket for low-latency updates from Robinhood’s feed
• Local RPC — HTTP 8547, WS 8548 when mapped

Data directory must land on /home/nitro/.arbitrum inside the container (the image runs as the nitro user). Config mounts at /home/nitro/config.

Hardware requirements

From Robinhood’s published table (full node). Archive needs substantially more disk.

Networked storage will throttle sync. Local NVMe is not a suggestion; it is the difference between “syncing” and “still syncing next week.”

Prerequisites

• Docker installed and running
• L1 execution RPC endpoint (your own synced node or a provider)
• L1 beacon URL for blob client access
• If you run your own L1, it must be fully synced before L2 can finish

Config files & genesis

Download Robinhood’s chain info (and mainnet genesis) from their docs site:

• Mainnet: robinhood-chain-info.json + robinhood-genesis.json
• Testnet: robinhood-chain-testnet-info.json (no custom genesis — omit --init.genesis-json-file)

Place them in something like $HOME/rh/config and mount that path into the container. Mainnet start commands pass both --chain.info-files and --init.genesis-json-file.

Running a mainnet node

Below is the public mainnet shape from Robinhood’s docs — the command pattern we followed. Substitute your own L1 execution and beacon URLs. Image pin from the docs: offchainlabs/nitro-node:v3.11.2-3599aca.

DATA_DIR="$HOME/rh/robinhood-nitro-data"
docker run --rm -it \
    -v "$DATA_DIR":/home/nitro/.arbitrum \
    -v "$HOME/rh/config":/home/nitro/config \
    -p 8547:8547 -p 8548:8548 \
    offchainlabs/nitro-node:v3.11.2-3599aca \
      --chain.info-files=/home/nitro/config/robinhood-chain-info.json \
      --parent-chain.connection.url=... \
      --parent-chain.blob-client.beacon-url=... \
      --init.genesis-json-file=/home/nitro/config/robinhood-genesis.json \
      --http.addr=0.0.0.0 --http.port=8547 \
      --http.api=net,web3,eth

Confirm ArbOS / Nitro versions before upgrades. On ArbOS upgrades, un-upgraded nodes stop cleanly and resume after updating — no data loss, per Robinhood’s notes.

Sequencer feed

For low-latency updates, subscribe to the sequencer feed. The URL must be wss://, not https://.

--node.feed.input.url=wss://feed.mainnet.chain.robinhood.com

Testnet feed (if you are on testnet): wss://feed.testnet.chain.robinhood.com.

RPC endpoints & ports

• Public Mainnet: https://rpc.mainnet.chain.robinhood.com
• Local HTTP (when running the container as above): http://localhost:8547
• Local WS: port 8548 (mapped in the docker command)
• Expose externally only if you set --http.addr=0.0.0.0 and understand the risk

Health checks

Is the node answering?

curl -d '{"id":0,"jsonrpc":"2.0","method":"eth_getBlockByNumber","params":["latest",false]}' \
  -H "Content-Type: application/json" http://localhost:8547

Sync status — a fully synced node returns false:

curl -d '{"id":0,"jsonrpc":"2.0","method":"eth_syncing","params":[]}' \
  -H "Content-Type: application/json" http://localhost:8547

Sending transactions before sync completes can surface nonce has already been used — wait. Watch docker logs for block production messages while you wait.

Syncing & snapshots

Initial sync can take a long time and burns L1 request quota. Monitor your provider. Optional faster path on first start: initialize from a snapshot with --init.url=<SNAPSHOT_URL> (documented by Robinhood as optional).

Validators, BoLD, bonds

Robinhood Chain uses BoLD for dispute resolution through a permissioned validator set. Operating a validator means being on the allowlist and staking a 1 WETH bond (defensive validators encouraged). Reach out to Robinhood to join the set — this is separate from running a read/sync full node for building.

Troubleshooting

General

• docker logs -f <container> for errors / restart loops
• Confirm host can reach L1 execution and beacon endpoints
• Unsynced L1 stalls L2 sync

Sync issues

• Most failures: unreachable beacon URL
• Keep system clock accurate (ntp / chrony)
• Slow sync: check disk I/O; avoid networked volumes

Connectivity

• Map 8547 (HTTP) and 8548 (WS)
• Ensure --http.addr=0.0.0.0 if you need external RPC

How this ties to rhDOGE

dogecoin but on robinhood is the product story on top of that node: Dogecoin aesthetic, Robinhood Chain rails, and an inverted fee model on our Explorer (users pay $0; we pay memecoin rewards for usage). The node is the credibility layer — Nitro, ArbOS 61, real ports, real feed URL — even when the front-of-house is meme-forward.

Canonical operator docs remain with Robinhood: docs.robinhood.com/chain/run-a-full-node.