Run a Local Devnet

Start a disposable local Base devnet with L1, L2 sequencer, RPC nodes, and batcher from the base/base repo, then send a test transaction.

The local devnet runs a complete Base stack on your machine with Docker: an L1 (Reth + Lighthouse), a Base sequencer, two RPC nodes, and a batcher. It also runs a shadow batcher and shadow validator used to test the Rust batcher. Use it to test node, protocol, and hardfork behavior without a public network.

To build against new Base features without running infrastructure, use the hosted Vibenet instead.

The devnet is disposable. just devnet up, just devnet up-single, and just devnet down delete all chain data in .devnet/. It publishes ports on all interfaces, so run it on an isolated development machine.

Prerequisites

• Docker with Compose v2 and Buildx. The first build compiles the Rust services, so allocate generous memory to Docker.
• just 1.51.0 or newer
• Foundry (cast) to send transactions
• jq, used by just devnet status and just devnet checks
• A clone of base/base

Start the Devnet

From the root of the base/base repo:

Terminal

just devnet up-single

This stops any running devnet, clears its data, builds the images, and starts a single-sequencer stack. The first run compiles the Rust services and takes several minutes.

Command	Starts
just devnet up-single	One sequencer. The fastest option for most testing.
just devnet up	A 3-node high-availability sequencer cluster with conductor.

Check that blocks are advancing:

Terminal

just devnet status

Send a Test Transaction

The devnet prefunds the standard Foundry/Anvil test accounts, listed in etc/docker/devnet-env. Send ETH through the sequencer:

Terminal

source etc/docker/devnet-env
cast send "$ANVIL_ACCOUNT_2_ADDR" --value 0.001ether \
  --private-key "$ANVIL_ACCOUNT_1_KEY" \
  --rpc-url http://127.0.0.1:7545

A receipt with status 1 confirms the sequencer included the transaction. To run the built-in L1 and L2 checks instead, use just devnet checks.

The test account keys are public. Never use them on Mainnet or Sepolia.

Endpoints

Service	URL	Chain ID
L2 sequencer (builder) RPC	http://127.0.0.1:7545	84538453
L2 RPC node	http://127.0.0.1:8545	84538453
L2 RPC node (base-rpc)	http://127.0.0.1:8645	84538453
L1 RPC	http://127.0.0.1:4545	1337
Grafana	localhost:3000

Ports are set in etc/docker/devnet-env.

Hardfork Activation

The devnet schedules Azul at L2 block 20, Beryl at 21, Cobalt at 22, and Denim at 25, so a fresh devnet crosses each activation within its first few blocks. At Denim, the sequencer switches to 200ms blocks.

Command	Also activates
just devnet up-single everest	Everest (EIP-8130 transactions) at block 100
just devnet up-single zenith	Everest and Zenith at block 100

The devnet’s canonical batcher (op-batcher) cannot decode EIP-8130 transactions (type 0x79). After the first block that contains one, it stops advancing and the canonical safe head stalls. The shadow base-batcher keeps deriving past those blocks. See the devnet README for details.

To move an activation, set L2_BASE_DENIM_BLOCK (or the matching L2_BASE_<HARDFORK>_BLOCK variable) before up or up-single. Set it to an empty value to leave that hardfork unscheduled.

Common Commands

Command	Does
just devnet accounts	Lists funded test accounts with balances and nonces
just devnet logs [container]	Streams logs, optionally for one container
just devnet ps	Shows container status
just devnet flashblocks	Streams Flashblocks from the builder. Requires Go on first use to install the client.
just devnet down	Stops the devnet and deletes its data

Run just devnet with no arguments for the full list.

Learn More

The base/base repo is the source of truth for the devnet:

• Devnet README: stack topology, batcher setup, the Anvil + Nitro proving variant, and upgrade-signal testing
• etc/docker/Justfile: every devnet command
• Testing guide: system tests against the devnet (just devnet tests)
• Standalone proving guide: run the prover stack, which the devnet does not include. ZK proving against a local devnet requires disabling Beryl and Cobalt.