> For the complete documentation index, see [llms.txt](https://docs.selcier.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.selcier.xyz/under-the-hood/network-foundation.md). # The network underneath Why Robinhood Chain is Selcier's home, its mainnet and testnet settings, the two levels of confirmation, and how Selcier behaves during a sequencer outage. Robinhood Chain, the network beneath Selcier, is an Ethereum layer 2 that uses Arbitrum technology and targets tokenized real-world assets. Because that network is permissionless, Selcier, an independent company, builds on it on the same terms as any other developer. ## Reasons for this chain **Existing stock token conventions.** Users and integrators already look to Robinhood Chain for stock tokens. The chain's wallets, DEXs and price feeds are familiar with what Robinhood Stock Tokens set out: a single ERC-20 for each asset, an ERC-8056 multiplier for corporate actions, and price feeds per asset that honor a pause flag. By following those same conventions, Selcier Share Tokens are compatible with this infrastructure from day one. **Primitives that already exist.** The network already has Chainlink feeds, BitGo institutional custody, the USDG stablecoin and established AMMs. Selcier uses these and does not try to replace them. **Settlement on Ethereum.** Blobs carry the chain's transaction data to Ethereum, and Ethereum's security extends to its settlement. Full EVM equivalence means wallets, audit practices and standard Solidity tooling need no changes. **Affordable per-transfer checks.** A company's transfer rules run on-chain for each Selcier transfer. Those checks stay practical even on small transfers, thanks to low fees and soft confirmation in under a second. With a permissionless chain, the network cannot be what limits who holds a token, and Selcier does not expect it to. Enforcement sits in the token contract, as described in [Compliance modules](/fundamentals/compliance-modules.md). ## Network settings **Mainnet** | Setting | Value | | -------------- | ------------------------------------------------ | | Chain ID | `4663` | | Gas token | ETH | | Public RPC | `https://rpc.mainnet.chain.robinhood.com` | | Block explorer | `https://robinhoodchain.blockscout.com` | | Sequencer feed | `wss://feed.mainnet.chain.robinhood.com` | | Delayed feed | `wss://delayed-feed.mainnet.chain.robinhood.com` | | Environment | Live (`api.selcier.xyz`) | **Testnet** | Setting | Value | | -------------- | ---------------------------------------------- | | Chain ID | `46630` | | Gas token | ETH | | Public RPC | `https://rpc.testnet.chain.robinhood.com` | | Block explorer | `https://explorer.testnet.chain.robinhood.com` | | Sequencer feed | `wss://feed.testnet.chain.robinhood.com` | | Delayed feed | Not available | | Environment | Sandbox (`api.sandbox.selcier.xyz`) | Rate limits apply to the public RPC endpoints, and production traffic should go elsewhere: a dedicated provider such as Chainstack, QuickNode or Alchemy is the right choice. Selcier's own setup is Alchemy first, with failover to Chainstack. Archive endpoints are required for event indexing and historical reads. You can find Selcier's contract addresses on both networks through `GET /v1/contracts` or in the [Explorer](https://explorer.selcier.xyz). ## Connecting a wallet Network configuration is not something most investors and employees ever see. Onboarding through Portfolio sets up an embedded wallet, and because Selcier sponsors the gas on all holder transactions, holding ETH is unnecessary. If you prefer an external wallet, define a custom network from the mainnet table. Enter `4663` as the chain ID and `ETH` as the currency symbol, then supply an RPC URL and the block explorer URL. On connection, Portfolio offers to add the network automatically on compatible wallets. Custom-network support is the only requirement for an EVM wallet, and BitGo institutional custody is also an option. ## Two levels of confirmation Selcier surfaces both of the milestones that a Robinhood Chain transaction goes through. | Milestone | Timing | Meaning | | -------------------------- | ------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------- | | **Sequencer confirmation** | Usually within a second | The transaction has been ordered and put on the feed. Normal operation treats the outcome, which is already known, as final. | | **Ethereum confirmation** | Once its batch has been posted to Ethereum | The transaction now belongs to data recorded on Ethereum, and Ethereum's settlement guarantees extend to it. | The Console and Portfolio treat sequencer confirmation as "confirmed", and that is why an offering close or a Liquidity Window clearing feels instant. Both milestones are shown in the Explorer per transaction. Webhook events carry a `confirmation` field whose value is `sequencer` or `l1`, leaving the choice of level to the integrator. [Event delivery](/build-on-selcier/event-delivery.md) has the details. Ordering is first-come, first-served by time of arrival. With no priority fee auction in the sequencer, settlement transactions get predictable ordering. ## Sequencer outages Force inclusion carries over from Arbitrum to Robinhood Chain. When the sequencer stops including transactions, any user can submit one to the chain's inbox contract on Ethereum, and it gets included after a protocol-set delay regardless of the sequencer's cooperation. So an outage can slow transactions down, but cannot censor a holder or permanently freeze the chain. Selcier takes a cautious stance while an outage lasts: | Area | Behavior during an outage | | -------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **Holder balances** | These stay as they were. They are contract state, and state through the last posted batch is on record at Ethereum. | | **Time-sensitive actions** | The default is to hold fresh submissions in the transaction queue and not send them to force inclusion, since forced transactions have less predictable order and timing. From the Console, a company may opt to force-include a particular transaction. | | **Liquidity Windows** | A window closing during an outage should be extended, by Selcier's recommendation, and the Console has a one-step action for this. | | **Valuations** | Updates to the `ValuationOracle` pause for the duration, so integrations see the last value along with its original timestamp. | After the sequencer returns, three things happen: the status page logs the incident, the queue drains in submission order, and the indexer uses the archive endpoint to catch up. ## Ecosystem connections | Integration | Role in Selcier | | ------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | **USDG** | Default settlement asset across distributions, RFQ trades, Liquidity Windows and offerings. A company can have other stablecoins enabled. | | **Chainlink** | `ValuationOracle` offers a Chainlink-compatible `latestRoundData` interface. Anything already reading Chainlink feeds on the chain can read Selcier's Reference Valuations with no code changes. | | **BitGo** | Custody at institutional grade, an alternative to self-custody when a company, fund or investor would rather use a qualified custodian. | | **AMMs** | Opt-in permissioned pools on the chain's DEX infrastructure, run by companies through `PoolGate`. See [Gated AMM pools](/markets-and-capital/gated-pools.md). | [Platform design](/under-the-hood/platform-design.md) shows how all of this connects within Selcier. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. 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