docs: add popkins (sepolia + celestia mocha) and local OP Stack & Nitro devnet guides

.github/workflows/lint.yaml

@@ -49,4 +49,4 @@ jobs:
         run: npm install --no-package-lock --legacy-peer-deps
 
       - name: Run Link Checker
-        run: npm run check-links -- --all --concurrency=2 --skip="celestia.org,nexus.hyperlane.xyz"
+        run: npm run check-links -- --all --concurrency=2 --skip="celestia.org,nexus.hyperlane.xyz,infura.io"

app/build/stacks/_meta.js

@@ -1,6 +1,6 @@
 const meta = {
-  "nitro-das-server": "Nitro DAS server",
-  "op-alt-da": "OP alt DA",
+  nitro: "Arbitrum Nitro",
+  optimism: "Optimism",
 };
 
 export default meta;

app/build/stacks/nitro/_meta.js

@@ -0,0 +1,7 @@
+const meta = {
+  "nitro-das-server": "Nitro DAS server overview",
+  "local-devnet": "Nitro local devnet",
+  "popkins-popsigner": "Deploy with Popkins and Popsigner",
+};
+
+export default meta;

app/build/stacks/nitro/local-devnet/page.mdx

@@ -0,0 +1,217 @@
+# Local Nitro devnet
+
+This guide will teach you how to spin up a complete local Arbitrum Nitro rollup with Celestia DA for testing.
+
+**What `pop-deployer` does:** It spins up a temporary Anvil instance, deploys all Nitro infrastructure contracts (`RollupCreator`, `Bridge`, `SequencerInbox`, `Outbox`, challenge manager, one-step provers, etc.), creates the rollup via `createRollup`, deploys WETH for BOLD staking, captures the chain state to a snapshot, then packages everything into a tarball. When you run the bundle, Anvil loads the pre-deployed state instantly - no waiting for contract deployments.
+
+import { Callout, Steps } from "nextra/components";
+
+<Callout type="info">
+    The "Build the bundle generator" and "Generate the pre-deployed bundle" steps will soon be available through the Popkins UI.
+</Callout>
+
+
+## Prerequisites
+
+See [overview of Popsigner and Popkins](/build/stacks/optimism/popkins-popsigner#overview).
+
+## Option 1: In the UI
+
+<Steps>
+
+### Log in to Popkins
+
+Go to https://popkins.popsigner.com and login.
+
+### Set up the local chain
+
+<Steps>
+
+#### New chain
+
+Click "+ NEW CHAIN" in the top right of the Popkins UI.
+
+Select "POPKINS BUNDLE" and click continue:
+
+![1.deploy-new-chain](/img/build/stacks/optimism/popkins-popsigner/1.deploy-new-chain.png)
+
+#### Pick stack
+
+Then select "ARBITRUM NITRO", put a chain name and chain ID into the fields, and click "🚀 CREATE BUNDLE".
+
+![2.pick_nitro](/img/build/stacks/optimism/popkins-popsigner/2.pick_nitro.png)
+
+#### Wait for bundle generation
+
+Wait for the bundle to be generated:
+
+![3.wait-for-deploy-nitro.png](/img/build/stacks/optimism/popkins-popsigner/3.wait-for-deploy-nitro.png)
+
+#### Review details
+After it has generated, review the details:
+
+![4.download-bundle-nitro](/img/build/stacks/optimism/popkins-popsigner/4.download-bundle-nitro.png)
+
+![4.1.look-at-details-nitro](/img/build/stacks/optimism/popkins-popsigner/4.1.look-at-details-nitro.png)
+
+</Steps>
+
+### Download the bundle
+
+Download the bundle by clicking the "DOWNLOAD BUNDLE" button.
+
+![5.download](/img/build/stacks/optimism/popkins-popsigner/5.download.png)
+
+### Extract the tarball
+
+Extract the tarball by running the following command:
+
+```bash
+unzip my-local-devnet-pop-bundle-artifacts.tar.gz
+cd my-local-devnet-pop-bundle-artifacts
+```
+
+### Run the bundle
+
+Run the bundle by running the following command:
+
+```bash
+docker compose up -d
+```
+
+</Steps>
+
+
+## Option 2: In the terminal
+
+<Steps>
+
+### Clone Popsigner
+
+```bash
+git clone https://github.com/celestiaorg/popsigner.git
+```
+
+### Build the bundle generator
+
+```bash
+cd popsigner/control-plane/cmd/pop-deployer
+go build -o pop-deployer .
+```
+
+### Generate the pre-deployed bundle
+
+```bash
+./pop-deployer --stack nitro
+```
+
+### Extract and run
+
+The bundle comes with all contracts already deployed and configured - just extract and run.
+
+```bash
+tar xzf nitro-local-devnet-bundle.tar.gz
+./scripts/start.sh
+```
+
+Verify it's running:
+
+```bash
+cast chain-id --rpc-url http://localhost:8547
+# 42069
+```
+
+This starts the following services:
+
+#### Services and ports
+
+| Service | Port | Description |
+|---------|------|-------------|
+| **Anvil** | `8545` (RPC) | L1 chain with pre-deployed Nitro contracts including:<br/>• `RollupCreator` - Factory for creating new rollups<br/>• `Bridge` - Cross-chain asset bridge<br/>• `SequencerInbox` - Receives L2 transactions<br/>• `Outbox` - Processes L2→L1 messages<br/>• Challenge manager & one-step provers for fraud proofs |
+| **Nitro Sequencer** | `8547` (RPC) | L2 execution and sequencing node (nitro-node) that:<br/>• Processes transactions<br/>• Produces blocks<br/>• Manages state transitions<br/>• Handles deposits and withdrawals |
+| **Localestia** | `26658` (Bridge API) | Mock Celestia DA layer providing:<br/>• Data availability for L2 batches<br/>• Blob storage and retrieval<br/>• DA attestations |
+| **POPSigner-Lite** | Internal | Local signing service that:<br/>• Signs batch data for Celestia DA<br/>• Manages validator keys<br/>• Provides attestation signatures |
+
+#### Default funded accounts (L1 only)
+
+<Callout type="warning">
+These are standard Anvil test accounts with publicly known private keys. **NEVER use these on mainnet or testnets!** They are only for local development.
+</Callout>
+
+The following accounts are pre-funded with 10,000 ETH on **L1 only**. You must bridge funds to L2 as shown in the examples below:
+
+| Account | Address | Private Key (TEST ONLY) |
+|---------|---------|-------------------------|
+| Account #0 | `0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266` | `0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80` |
+| Account #1 | `0x70997970C51812dc3A010C7d01b50e0d17dc79C8` | `0x59c6995e998f97a5a0044966f0945389dc9e86dae88c7a8412f4603b6b78690d` |
+| Account #2 | `0x3C44CdDdB6a900fa2b585dd299e03d12FA4293BC` | `0x5de4111afa1a4b94908f83103eb1f1706367c2e68ca870fc3fb9a804cdab365a` |
+| Account #3 | `0x90F79bf6EB2c4f870365E785982E1f101E93b906` | `0x7c852118294e51e653712a81e05800f419141751be58f605c371e15141b007a6` |
+| Account #4 | `0x15d34AAf54267DB7D7c367839AAf71A00a2C6A65` | `0x47e179ec197488593b187f80a00eb0da91f1b9d0b13f8733639f19c30a34926a` |
+
+<Callout type="info">
+To use these accounts on L2, you must first bridge funds from L1 using the deposit function as shown in the "Fund your L2 account" step below.
+</Callout>
+
+These are the standard Anvil development accounts and are safe to use in documentation since they're universally known test keys.
+
+</Steps>
+
+Congratulations! You've successfully deployed a Nitro local devnet.
+
+### Testing with a smart contract
+
+<Steps>
+
+#### Fund your L2 account
+
+```bash
+cast send 0x72d8D69ae87568ab98C2A652F7B8feE62fBB862b "depositEth()" \
+  --value 1ether \
+  --rpc-url http://localhost:8545 \
+  --private-key 0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80
+```
+
+Wait ~10 seconds for the deposit to process, then verify:
+```bash
+cast balance 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266 --rpc-url http://localhost:8547
+```
+
+#### Deploy a contract
+
+```bash
+rm -rf /tmp/counter && mkdir -p /tmp/counter && cd /tmp/counter
+forge init
+cat > src/Counter.sol << 'EOF'
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.20;
+
+contract Counter {
+    uint256 public count;
+    function increment() public { count += 1; }
+}
+EOF
+forge create src/Counter.sol:Counter \
+  --rpc-url http://localhost:8547 \
+  --private-key 0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80 \
+  --broadcast
+```
+
+#### Interact with it
+
+```bash
+cast call 0x5FbDB2315678afecb367f032d93F642f64180aa3 "count()" --rpc-url http://localhost:8547
+```
+
+```bash
+cast send 0x5FbDB2315678afecb367f032d93F642f64180aa3 "increment()" \
+  --rpc-url http://localhost:8547 \
+  --private-key 0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80
+```
+
+```bash
+cast call 0x5FbDB2315678afecb367f032d93F642f64180aa3 "count()" --rpc-url http://localhost:8547
+```
+
+</Steps>
+
+You've now deployed and interacted with a smart contract on your local Nitro devnet.