Network & Protocol Guides
Reading Solana Accounts: getAccountInfo, Rent Exemption, and Token Balances
Learn how Solana account data, rent, and SPL token balances work, and which RPC method to use for each read.
Read articleOnFinality Learn
Practical knowledge for Web3 builders
Technical explainers, troubleshooting playbooks, and infrastructure guidance shaped by the questions developers search for.
All topicsNetwork & Protocol GuidesRPC TroubleshootingInfrastructure & Operations
OnFinality Learn
87Latest articles
Network & Protocol Guides
Reading Sui Objects Over RPC: getObject, Dynamic Fields, and Pagination
Learn how to read Sui objects via JSON-RPC: getObject, multiGetObjects, dynamic fields, owned objects, and cursor pagination.
Read articleNetwork & Protocol Guides
Ethereum eth_subscribe: Logs and Head Subscriptions vs Polling Filters
Learn Ethereum's eth_subscribe push model: newHeads, logs, lifecycle, reconnect handling, and when to poll instead.
Read articleNetwork & Protocol Guides
Tracking Base Cross-Chain Events: Deposit Logs and Withdrawal Proofs
Learn to parse L1->L2 deposit logs and L2->L1 withdrawal proofs on Base using RPC, with runnable examples and troubleshooting.
Read articleNetwork & Protocol Guides
Hyperliquid Oracle Prices and the Builder Auction: Reading Market State
Learn how Hyperliquid derives oracle prices and how the builder/data-availability auction selects block producers, then read that state via the info API.
Read articleNetwork & Protocol Guides
Reading Bittensor Metagraph State: Weights, Emissions, and Dividends from a Subtensor Node
Learn how to read the Bittensor metagraph from a subtensor node: weights, consensus, emissions, dividends, and reproducible verification methods.
Read articleNetwork & Protocol Guides
Ethereum eth_getLogs: Filtering Event Logs by Address and Topics
Learn how eth_getLogs topic filters work, how to query ERC-20 Transfer events efficiently, and how to avoid common pitfalls.
Read articleNetwork & Protocol Guides
Reading the Ethereum Mempool: The txpool Namespace and Pending Transactions
Learn how the Ethereum mempool works, how to inspect it with txpool_* RPC methods, and why hosted providers rarely expose it.
Read articleNetwork & Protocol Guides
Estimating Gas Price with eth_feeHistory: Base Fee and Priority Fee Percentiles
Learn to read eth_feeHistory and build a robust EIP-1559 gas estimator using base fee and priority fee percentiles.
Read articleNetwork & Protocol Guides
Solana Blockhash Expiry and Durable Nonces: Safe Offline Signing
Why Solana transactions expire via lastValidBlockHeight, and how durable nonces enable safe offline signing.
Read articleNetwork & Protocol Guides
Substrate state_getMetadata and Runtime Versions: Querying Chain Metadata at Any Block
Learn how to query Substrate runtime metadata at any block, understand metadata versions, and avoid decoding failures across runtime upgrades.
Read articleRPC Troubleshooting
Ethereum Transaction Tracing: trace_transaction vs debug_traceTransaction and trace_call
Understand Ethereum's trace and debug RPC families, when to use trace_transaction vs debug_traceTransaction, and how to run them.
Read articleNetwork & Protocol Guides
Polkadot Finality: GRANDPA Justifications, Finalized Head, and waitForFinalized over JSON-RPC
Learn how Polkadot's GRANDPA finality works and how to query, subscribe, and wait for the finalized head over JSON-RPC to avoid treating un-finalized blocks as permanent.
Read articleRPC Troubleshooting
Detecting RPC Node Head Lag and Stale Responses
Learn how to detect if your RPC node is behind the chain tip, measure head lag, and avoid stale responses.
Read articleInfrastructure & Operations
Checking Base OP-Stack Node Sync Status via op-node and op-reth Engine/Admin RPC
Learn how to verify Base node sync status using op-node and op-reth Engine/Admin RPC, detect stuck sync, and keep your node at the tip.
Read articleNetwork & Protocol Guides
Monad Transaction Lifecycle: Asynchronous Execution, Receipt Status, and Ordering
Understand Monad's async execution: how transaction receipts, status, and ordering differ from classic EVM chains, with a polling script.
Read articleRPC Troubleshooting
EVM Nonce Management: Using eth_getTransactionCount Correctly Under Concurrency
Learn how to manage EVM nonces correctly with eth_getTransactionCount to avoid nonce too low, stuck transactions, and concurrency issues.
Read articleNetwork & Protocol Guides
Base OP-Stack Finality: Safe, Finalized, and Latest Block Tags over RPC
Understand Base OP-Stack finality stages and how to use safe, finalized, and latest block tags in JSON-RPC calls.
Read articleNetwork & Protocol Guides
eth_getProof (EIP-1186): Account and Storage Proofs for State Verification
Learn how Ethereum state proofs work and how to use eth_getProof to fetch and independently verify account and storage values over JSON-RPC.
Read articleNetwork & Protocol Guides
Simulating Sui Transactions Before Sending: devInspectTransaction and dryRunTransactionBlock
Learn how to simulate Sui transactions via JSON-RPC to catch object version conflicts, gas issues, and command failures before paying gas.
Read articleRPC Troubleshooting
Migrating Off Deprecated Solana RPC Methods: getConfirmedBlock and Legacy getConfirmed API Calls
Learn how to migrate from deprecated Solana getConfirmed* RPC methods to the canonical getBlock, getSignaturesForAddress, getTransaction, and getSlot family with explicit commitment.
Read articleRPC Troubleshooting
Ethereum Revert Reasons and Custom Errors: Decoding Why a Transaction or eth_call Fails
Learn how to decode Ethereum revert reasons and custom errors from JSON-RPC responses, including Error(string), Panic(uint256), and custom error selectors.
Read articleNetwork & Protocol Guides
eth_call State Override: Simulating Ethereum Calls Against Hypothetical State
Learn to use eth_call's state override set to simulate calls against modified state—no transaction needed. Includes viem/ethers examples.
Read articleRPC Troubleshooting
Decoding Solana simulateTransaction Errors: Instruction Index, Program ID, and Custom Error Codes
Learn to read and fix Solana simulateTransaction preflight errors: decode instruction index, program ID, and custom error codes from JSON-RPC logs.
Read articleRPC Troubleshooting
Decoding Polkadot Extrinsic Submission Errors: 1010 Invalid Transaction and Dispatch Failures
Learn to decode Polkadot RPC 1010 Invalid Transaction tags and dispatch errors, with a runnable @polkadot/api script and fix checklist.
Read articleRPC Troubleshooting
Hyperliquid API Error Handling: Decoding Order Rejections, Margin, and Oracle Checks
Decode Hyperliquid /info and /exchange order rejections: margin, risk limits, open interest caps, oracle price checks, and post-only guardrails.
Read articleNetwork & Protocol Guides
Ethereum Archive Node and Historical RPC: Querying Past Balances, Logs, and State
Learn what an Ethereum archive node stores, how to query historical balances, logs, and state via RPC, and how to verify your endpoint actually serves archive data.
Read articleNetwork & Protocol Guides
Polygon Archive Nodes and Historical RPC: Querying Past Polygon State Over JSON-RPC
Learn how Polygon PoS archive nodes work, how to query historical balances, state, and logs over JSON-RPC, and how to verify your endpoint truly serves archive data.
Read articleNetwork & Protocol Guides
Base Archive Node Historical RPC: Querying Past Base State and Logs
Learn how to query historical Base state and logs over OP-Stack JSON-RPC, what an archive node is on Base, and how to verify past balances, storage, and proofs with eth_getProof.
Read articleNetwork & Protocol Guides
Solana Versioned Transactions and getBlock/getTransaction Parsing: v0, Address Lookup Tables, and Decoding
Learn how to parse Solana versioned transactions (v0) returned by getBlock and getTransaction, including address lookup tables, version flags, and decoding steps with a runnable script.
Read articleRPC Troubleshooting
Bittensor RPC Timeout Errors on Subtensor: Why Calls Time Out and How to Retry Reliably
Learn why Bittensor (subtensor) RPC calls time out and how to handle them. Covers Substrate-specific timeouts, diagnostic scripts, and retry strategies.
Read articleNetwork & Protocol Guides
BNB Smart Chain Historical RPC and Archive Data: Querying Past Balances, Logs, and State
Learn how to query historical BNB Smart Chain (BSC) data over RPC, when you need an archive node, and how to avoid common pitfalls with eth_getBalance, eth_getLogs, and more.
Read articleNetwork & Protocol Guides
Polkadot and Substrate Archive Nodes: Querying Historical State Over RPC
Learn how archive nodes on Polkadot and Substrate chains store full historical state and how to query past storage values via state_getStorage and related RPC methods.
Read articleNetwork & Protocol Guides
Hyperliquid Historical Data and Market Data APIs: Querying Trades, OHLCV, Funding, and Order Book History
Learn how to retrieve Hyperliquid historical market data for analysis and backtesting using the native /info API, WebSocket feeds, and documented archives. Includes code examples and troubleshooting.
Read articleRPC Troubleshooting
Monad RPC Latency: Measuring, Bottlenecks, and Optimizing Query Speed
Learn how to measure Monad RPC latency, understand the bottlenecks unique to Monad's parallel execution and sub-second blocks, and optimize your queries for speed.
Read articleNetwork & Protocol Guides
Polkadot RPC Latency: Substrate Data Path, Measuring, and Optimization
Learn what drives Polkadot RPC latency, how to measure it reproducibly, and how to optimize your Substrate-based RPC calls.
Read articleNetwork & Protocol Guides
Sui Archive Nodes and Historical RPC: Checkpoints, Epochs, and Querying Past State
Learn how Sui archive nodes work, how to query historical state via checkpoints and epochs, and how to access archive data through RPC or your own node.
Read articleNetwork & Protocol Guides
Monad Historical RPC and Archive Data: Querying Past Blocks, Balances, and State
Learn how to query historical Monad data over RPC: archive vs full nodes, methods for past blocks and state, and a runnable ethers script to page eth_getLogs.
Read articleNetwork & Protocol Guides
Monad WebSocket RPC: WSS Endpoints, eth_subscribe, and Reliable Real-Time Streams
Learn how to connect to Monad's WebSocket RPC, use eth_subscribe for real-time data, and build resilient subscriptions with reconnection and resubscribe logic.
Read articleRPC Troubleshooting
Polygon RPC Timeouts: Causes, Diagnosis, and Retry Patterns
Learn why Polygon RPC calls time out, how to diagnose transport vs method-level timeouts, and how to implement robust retry patterns with exponential backoff for Polygon PoS.
Read articleNetwork & Protocol Guides
Base RPC Latency: Measuring, OP-Stack Factors, and Optimizing Query Speed
Learn how to measure Base RPC latency, understand OP-Stack factors like block time and L1 settlement, and optimize query speed with practical techniques.
Read articleNetwork & Protocol Guides
Hyperliquid RPC Latency: Measuring, HyperEVM vs Native API, and Low-Latency Tuning
Learn how to measure Hyperliquid RPC latency across the native L1 API and HyperEVM, understand the key differences, and apply low-latency tuning for trading.
Read articleRPC Troubleshooting
Sui RPC Timeouts: JSON-RPC vs gRPC, QueryWeight, and Reliable Retry Patterns
Learn why Sui RPC requests time out, how QueryWeight and transport choices affect timeouts, and how to diagnose and fix them with retry patterns and endpoint failover.
Read articleRPC Troubleshooting
Monad RPC Rate Limits and 429s: Per-IP Caps, Batching, and Backoff
Learn how Monad RPC endpoints enforce rate limits, why you get 429 Too Many Requests, and how to handle them with batching, caching, and exponential backoff.
Read articleRPC Troubleshooting
Monad RPC Timeouts: Causes, Diagnosis, and Reliable Retry Patterns
Learn why Monad RPC requests time out and how to fix them: distinguish transport vs method-level timeouts, diagnose with curl and eth_blockNumber, and implement robust retry and failover patterns in ethers.js and viem.
Read articleNetwork & Protocol Guides
Polygon WebSocket RPC: WSS Endpoints, eth_subscribe, and Reconnection
Learn how to connect to Polygon PoS WebSocket RPC endpoints, subscribe to newHeads and logs, handle reconnections, and avoid common pitfalls.
Read articleNetwork & Protocol Guides
Ethereum RPC Latency: Measuring, Optimizing, and Reducing Query Delays
Learn what drives Ethereum RPC latency, how to measure it with a reproducible script, and how to optimize queries for lower effective latency.
Read articleNetwork & Protocol Guides
Bittensor WebSocket RPC: Substrate Subscriptions and Reliable Streams
Learn how to use Bittensor's WebSocket RPC for real-time Substrate subscriptions: chain heads, storage, and extrinsics, with a Node.js example and troubleshooting.
Read articleNetwork & Protocol Guides
Solana RPC WebSocket: Pubsub Methods, Subscriptions, and Connection Lifecycle
Learn how to use Solana's PubSub WebSocket API for real-time account, program, and log subscriptions, with a Node.js example and troubleshooting guide.
Read articleRPC Troubleshooting
Polkadot RPC Rate Limits and 429s: Per-Second Limits, Flags, and Handling
Understand Polkadot RPC rate limits: Substrate flags, public endpoint restrictions, and how to handle 429s with batching, caching, and backoff.
Read articleNetwork & Protocol Guides
BNB Smart Chain WebSocket RPC: WSS Endpoints, eth_subscribe, and Reconnection
Learn how to connect to BNB Smart Chain via WebSocket RPC, use eth_subscribe for real-time data, and handle reconnections with ethers.js and web3.js.
Read articleRPC Troubleshooting
Bittensor (TAO) RPC Rate Limits and 429s: Per-IP Caps, Submit, and Retry Strategies
Learn how Bittensor (Finney) RPC endpoints enforce per-IP rate limits, why you get 429s, and how to stay under caps with subscriptions, batching, and backoff.
Read articleNetwork & Protocol Guides
Sui RPC Latency: Measuring, gRPC vs JSON-RPC, and Optimizing Query Speed
Learn what drives Sui RPC latency, how to measure it with a reproducible script, and how to optimize query speed using gRPC, multiGet, and pagination.
Read articleRPC Troubleshooting
Base RPC Timeouts: Causes, Diagnosis, and Retry Patterns for OP-Stack
Learn why Base RPC requests time out, how to diagnose transport vs method-level timeouts, and how to implement robust retry patterns with exponential backoff for OP-Stack L2s.
Read articleRPC Troubleshooting
Polkadot RPC Timeouts: WsProvider Reconnects, Block RPC Limits, and Reliable Queries
Learn why Polkadot RPC timeouts happen, how polkadot.js WsProvider handles disconnects, and how to build resilient queries with timeouts, reconnects, and batching.
Read articleRPC Troubleshooting
Hyperliquid RPC Timeouts: Rate Caps, HyperEVM Endpoints, and Reliable Retries
Hyperliquid RPC timeouts usually stem from the public HyperEVM endpoint's ~100 req/min per-IP cap. Learn to diagnose, avoid, and handle timeouts with caching, backoff, and idempotent retries.
Read articleNetwork & Protocol Guides
BNB Smart Chain RPC Latency: Measuring, Benchmarks, and Optimizing for DeFi
Learn what drives BNB Smart Chain RPC latency, how to measure it for your region and workload, and how to optimize for DeFi trading and indexing.
Read articleRPC Troubleshooting
Ethereum RPC Timeouts: Provider Config, eth_getLogs, and Retry Patterns
Learn why Ethereum RPC timeouts happen in ethers.js, viem, and go-ethereum, and how to fix them with provider timeouts, query optimization, and retry patterns.
Read articleRPC Troubleshooting
Solana RPC Timeouts: Causes, Retry Strategy, and Reliable Transaction Sending
Learn why Solana RPC calls time out, how to distinguish transport vs method timeouts, and implement a robust retry strategy for sending transactions with @solana/web3.js.
Read articleRPC Troubleshooting
Solana RPC Latency: Measuring, Sources, and Optimization for Trading and dApps
Learn what drives Solana RPC latency, how to measure it with a reproducible script, and when to move from public to dedicated endpoints for trading bots.
Read articleNetwork & Protocol Guides
Querying Solana Historical Data Over RPC: Methods, Limits, and Production Patterns
Learn how to query Solana historical data via JSON-RPC: getSignaturesForAddress, getTransaction, getBlock, and pagination patterns, with practical limits and production considerations.
Read articleRPC Troubleshooting
Ethereum RPC Rate Limits and 429 Errors: Method Costs, Compute Units, and Mitigation
Learn how Ethereum RPC providers meter requests by compute-unit cost, why eth_getLogs and archive methods dominate, and how to fix 429 errors with batching, caching, backoff, and dedicated endpoints.
Read articleRPC Troubleshooting
Polygon RPC 429 Errors and Rate Limits: Causes, Diagnosis, and Fixes
Polygon RPC 429 errors occur when requests exceed rate limits. Learn the causes, how to diagnose them, and practical fixes including batching, WebSocket subscriptions, and backoff strategies.
Read articleRPC Troubleshooting
Sui RPC Rate Limits and Compute Units: Managing Cost and 429s in Production
Learn how Sui RPC rate limits and compute-unit accounting work, how to avoid 429s with pagination and cost-shaping queries, and how to handle backoff in the Sui TypeScript SDK.
Read articleNetwork & Protocol Guides
Hyperliquid WebSocket Subscriptions: Connection Lifecycle, Feeds, and Reconnection
Learn how to subscribe to Hyperliquid's real-time WebSocket feeds (l2Book, trades, candles, allMids, userEvents, orderUpdates), handle heartbeats, and implement a robust reconnection strategy with runnable Python and Node.js examples.
Read articleNetwork & Protocol Guides
Bittensor RPC Performance and Latency: Measuring Endpoints Before You Choose
Learn how to measure Bittensor (TAO) RPC latency and performance yourself, understand the Substrate JSON-RPC surface, and choose between hosted endpoints and running your own node.
Read articleRPC Troubleshooting
Base RPC Rate Limits and Reliability: Provider Limits, Monitoring, and Scaling
Understand Base RPC rate limits, 429 errors, and how to build a reliable setup with monitoring, failover, and scaling strategies.
Read articleRPC Troubleshooting
BNB Smart Chain RPC Reliability and Timeouts: Public Endpoint Failures and Production Setups
Public BSC RPC endpoints can fail or time out under load. Learn why, how to set timeouts and retries, monitor health, and build a fallback chain for production.
Read articleNetwork & Protocol Guides
Base RPC WebSocket Connections: Endpoints, Flashblocks, and Reliability
Learn how to connect to Base mainnet and Sepolia via WebSocket RPC, use Flashblocks for sub-second block events, and build reliable subscriptions with ethers.js and viem.
Read articleNetwork & Protocol Guides
Bittensor RPC and Node Access: Running a Node and Connecting to Finney
Learn how to run a Bittensor (TAO/Finney) Substrate node, choose between lite and archive modes, connect via WSS RPC, and verify node health with JSON-RPC calls. Includes a decision guide for self-hosted vs hosted RPC endpoints.
Read articleRPC Troubleshooting
BNB Smart Chain RPC Rate Limits and 429s: What They Are and How to Handle Them
Learn why BNB Smart Chain RPC endpoints return 429 Too Many Requests, how rate limits work, and practical fixes including retry with backoff, eth_getLogs optimization, WebSocket subscriptions, and moving to a dedicated endpoint.
Read articleRPC Troubleshooting
Ethereum WebSocket RPC Disconnects: Causes and Reconnection with ethers.js and web3.js
Learn why Ethereum WebSocket RPC connections drop and how to implement robust reconnection logic in ethers.js and web3.js, with runnable code examples.
Read articleRPC Troubleshooting
Hyperliquid API Rate Limits: Info vs Exchange Endpoints and Compliance
Learn how Hyperliquid's /info and /exchange endpoints differ in rate limits, how to compute usage, and best practices for staying within limits.
Read articleNetwork & Protocol Guides
Monad RPC Endpoints: Testnet Setup, Methods, and Latency
Learn how to connect to Monad's EVM-compatible JSON-RPC endpoints, add Monad to MetaMask, run curl examples, and validate endpoint health and latency.
Read articleNetwork & Protocol Guides
Polkadot WebSocket RPC: WSS Endpoints, Subscriptions, and Reconnection
Learn how Polkadot's WebSocket RPC works, how to use @polkadot/api subscriptions, and how to handle disconnections and secure WSS endpoints.
Read articleRPC Troubleshooting
Why Polygon RPC Is Slow: Latency Causes, Measurement, and Fixes
Polygon RPC latency can stem from Bor/Heimdall architecture, archive data, heavy queries like eth_getLogs, and shared endpoints. Learn how to measure and fix it.
Read articleRPC Troubleshooting
Solana RPC Rate Limits and 429 Errors: How They Work and How to Fix Them
Understand Solana RPC rate limits, request-unit costs, and 429 errors. Learn practical fixes using Web3.js, caching, and dedicated endpoints.
Read articleNetwork & Protocol Guides
Sui RPC WebSocket Subscriptions: Event Streams and Best Practices
Learn how to use Sui's WebSocket subscription interface to stream events, checkpoints, and epochs in real time. Includes runnable TypeScript examples, expected payload shapes, and best practices for reconnection and rate limits.
Read articleNetwork & Protocol Guides
How to Query Historical Blockchain Data via RPC
Learn the difference between full, archive, and trace nodes, and how to query past state with eth_getBlockByNumber, eth_call, eth_getCode, and eth_getStorageAt.
Read articleInfrastructure & Operations
Archive Node vs Full Node: What's the Real Difference?
Understand the data retention, query capability, and cost tradeoffs between full, archive, and trace nodes on EVM chains, and when you actually need archive RPC access.
Read articleRPC Troubleshooting
Why Your WebSocket RPC Disconnects and How to Fix It
Learn why JSON-RPC WebSocket connections drop (idle timeouts, close codes 1006/1008/1001) and how to build resilient reconnection with keepalive and backoff.
Read articleRPC Troubleshooting
How to Fix RPC 429 Too Many Requests Errors
Learn why blockchain RPC endpoints return HTTP 429 errors and how to recover with backoff, batching, caching, and production-ready request controls.
Read articleRPC Troubleshooting
RPC Timeout Error: Causes, Diagnosis, and Fixes
Learn why blockchain JSON-RPC requests time out, how to diagnose timeouts with curl and client logs, and how to fix them in production.
Read articleRPC Troubleshooting
RPC Latency Slow: Causes, Measurement, and Fixes
Learn what drives blockchain JSON-RPC latency, how to measure it with curl, and how to reduce it using geographic endpoints, batching, and caching.
Read articleRPC Troubleshooting
JSON-RPC Batch Requests: Format, Examples, and Best Practices
Learn the JSON-RPC 2.0 batch request format, how to send multiple calls in one HTTP request, and when to use batching to reduce latency and improve throughput.
Read articleInfrastructure & Operations
RPC Node Monitoring: Metrics, Alerts, and Failover
Learn how to monitor blockchain RPC endpoints and nodes with Prometheus, Grafana, health checks, and alerting, plus how to build high-availability failover.
Read articleInfrastructure & Operations
Public RPC Endpoint Risks: What to Know Before Going to Production
Free public RPC endpoints are convenient but risky for production. Learn about rate limits, data consistency, security, and when to switch to dedicated endpoints.
Read article
Ethereum
Solana
Polygon
Base
Arbitrum
BNB Chain
Polkadot
Optimism
