Enterprise Blockchain Indexing for Analytics, Audits, and Compliance Dashboards

2025 Blueprint for Enterprise-Grade Blockchain Indexing

Introduction

A Vision for a Powerful Blockchain Indexing Solution

This blueprint maps out an exciting vision for a solid blockchain indexing solution that meets the needs of enterprises. We're aiming to support analytics, audits, and compliance dashboards across a range of networks like Ethereum L1/L2, Solana, and Cosmos.

Key Features

• Comprehensive Indexing: We're all about offering super deep indexing across various blockchain networks, helping businesses get easy access to their data and analyze it effectively.
• Real-Time Analytics: Dive into insights from blockchain data in a flash--this info is vital for making those key decisions and planning strategically.
• Robust Compliance Dashboards: Keep your compliance game strong with dashboards designed to meet the latest regulatory standards like MiCA, DAC8, DORA, OFAC, and FinCEN.

Technical Specifications

To reach these goals, we’ve laid out some solid configurations, schemas, and controls that will help steer the implementation of this solution.

Configuration

• Node Setup: We're rolling out dedicated nodes for each blockchain network to keep things running smoothly and reliably.
• Data Sources: We’re bringing in a bunch of different data sources, including wallets, exchanges, and smart contracts, to get a complete picture.

Schemas

• Database Structure: We’ve got a solid schema in place for keeping all that blockchain data organized. This includes transaction records, asset movements, and compliance flags, so everything’s on point.
• API Design: Our APIs are super user-friendly, making it a breeze for various systems to interact with the blockchain data without any hiccups.

Controls

• Access Management: Setting up strong access controls to make sure that only the right people can see or handle sensitive information.
• Audit Trails: Keeping thorough logs of all data interactions to back up audits and compliance reviews.

Conclusion

This blueprint is designed to make blockchain indexing super accessible and efficient for businesses. It’s a great fit with today’s regulations and what’s on the horizon. By sticking to these guidelines, organizations can harness the benefits of blockchain while staying compliant with all essential requirements.

Why indexing strategy is a board-level issue in 2025

Blockchain data really evolved between 2024 and 2025. Thanks to Ethereum’s Dencun and Pectra upgrades, we noticed a big change where high-volume L2 data began to be stored in temporary “blobs” at the consensus layer. This not only increased blob throughput but also challenged the old idea that traditional RPC log pollers could manage everything. Plus, with the rollout of account abstraction (ERC‑4337), we got a whole new “UserOperation” layer, bringing in new events and actors that we need to keep an eye on.

On Solana, the way to get top-tier indexing has shifted towards using Geyser plugins that stream data straight into Kafka, leaving the old JSON-RPC polling in the dust. There's also a lot happening on the regulatory front: MiCA is officially live in the EU, the DAC8 crypto tax reporting kicks off on January 1, 2026, and DORA's operational resilience requirements will start rolling out on January 17, 2025. Over in the U.S., things are getting intense too, with fresh sanctions from OFAC and some proposed rules from FinCEN regarding CVC mixers, which means more layers to keep track of when it comes to monitoring and recordkeeping. (blog.ethereum.org)

In this post, we’ll dive into the changes and lay out a simple architecture for you. Plus, I’ve thrown in some examples that you can start using right off the bat.

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What changed that breaks old indexers

• Alright, so EIP‑4844 blobs aren’t just hanging out in the execution layer payload; they’re actually chilling with the beacon node as “sidecars” and get pruned after around 18 days. If your indexer is just hitting up eth_getLogs, you’re really going to miss that L2 batch data stored in those blobs. To keep and query L2 data past that 18-day mark, you’ve got to dive into a consensus-layer path (like the Beacon API) or roll with a specialized blob indexer. (eips.ethereum.org)
• Pectra is set to launch on May 7, 2025, at epoch 364,032, and with EIP‑7691, we're cranking up blob capacity. We're now expecting around 6 blobs on average, with a peak of 9! This increase is going to enhance L2 posting throughput, but we'll need to get our heads together on scaling blob ingestion and archival while keeping an eye on costs. Check out more details in the Ethereum blog.
• Layer 2 solutions like OP Stack and Arbitrum can easily toggle between using blobs and calldata when they’re sending out batches. This means you’ll want to make sure your pipeline is ready to handle both methods and to note which one was used for every batch. For more info, take a look at the docs.optimism.io.
• Finality semantics are super important for how everything works. By leveraging the JSON-RPC block tags “safe” and “finalized,” you can easily keep track of your “freshness” and “completeness” service level agreements (SLAs). For example, you might want to trigger downstream jobs at the “safe” level, while audit exports can be set to occur when things are “finalized.” (ethereum.org)
• ERC‑4337 introduced these awesome EntryPoint-mediated "bundles" of UserOperations. To keep everything clear and easy to follow, it’s important to index stuff like EntryPoint calls (handleOps), UserOperation hashes, Paymaster flows, and even track how your bundler is doing. Most of the big players have made the switch to EntryPoint v0.7, and they’ve also standardized the addresses across various chains. You can dive deeper into it here: (docs.erc4337.io)
• Solana’s production indexing leverages validator-side Geyser plugins, pairing them up with Kafka or RabbitMQ sinks, along with allowlists and batching. This setup is great for handling slot skips and the rollbacks that pop up during reorgs. On top of that, some awesome logging and filtering updates were introduced in late 2024/2025 to keep things running smoothly. Take a look on GitHub!

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A 2025 reference architecture (multi‑chain, verifiable, cost‑aware)

Think of it in three layers: ingest, model, and serve. And don’t forget to keep an eye on observability throughout the entire process.

Ingest plane

• Ethereum L1/L2 (execution):
  • If you're diving into traces and logs, you'll want a high-performance client. Here are a couple of solid options:
    • Erigon is a great choice--just make sure to turn on rpcdaemon for the eth/debug/trace namespaces if you're looking for those detailed parity-style traces.
    • Alternatively, you might want to give Reth a shot if you prefer faster ad-hoc and filtered tracing with the trace_* and debug_* options.
  • When it comes to Erigon, here are some flags you should definitely consider:
    • --http.api=eth,erigon,debug,trace,txpool. And don’t forget to fire up rpcdaemon in a separate process; it’s a game-changer for boosting your throughput.
  • So, why go through all this trouble? Well, capturing full externality traces--like those internal ETH transfers and contract creations--is crucial for audits and revenue analytics. Check out the details here!
• Ethereum L1/L2 (consensus & blobs):
  • If you're looking to add a blob path, you've got a couple of options:
    • Use the Beacon API together with blob sidecars; or
    • Check out open-source blob explorers/indexers like Blobscan. They can help you pull, store, and serve blob contents before they get pruned. Just remember to keep a retention buffer of 30-90 days in your object storage. (eips.ethereum.org)
• Firehose/Substreams (multi-chain streaming):
  • Substreams lets you easily compute deterministic and parallelized state, like ERC-20 balances and DEX fills, and stream that data right into SQL/Parquet sinks. The latest upgrades have introduced some really neat features, like map-SQL/Parquet codegen, the option to store “time-travel” queries, Foundational Stores, and Substreams RPC v3 (.spkg ingestion). These enhancements mean you can move away from those pesky, fragile per-protocol ETLs and use reusable modules instead. Definitely worth a look on The Graph forum!
• Solana:
  • Get your Geyser plugin up and running to send accounts and transactions to either Kafka or RabbitMQ. Don’t forget to use program_allowlist for filtering so you can keep an eye on cardinality and costs. Also, tweak those producer queue sizes to avoid any drops from backpressure. (github.com)
• Cosmos (CometBFT chains):
  • You can easily index ABCI events and tags (type.key=value) using transaction/block search endpoints or WebSocket subscriptions. Just remember to create your event keys with compliance in mind--something like transfer.sender and transfer.recipient works well. For all the specifics, take a look here!
• Third-party datasets:
  • BigQuery's public crypto datasets can be super useful for quick analyses. Just remember to check how current the info is for each chain, and it’s a good idea to have some backup plans in place. For instance, the public Solana tables faced delays of several days back in 2025. Think of these datasets like a handy “golden check,” but don’t count on them as your main go-to for near-real-time data. (discuss.google.dev)

Storage and modeling plane

• Bronze (raw):
  • First off, grab all those raw execution logs, traces, blob payloads, and validator feeds, and throw them into object storage as compressed Parquet files. Make sure you keep things organized with the format chain_id=…/dt=YYYY‑MM‑DD, and if you’re up for it, you can add block_range too. Using a data lake with Iceberg/Delta is pretty handy because it helps you deal with ACID merges for any late data and adjustments for reorgs.
• Silver (normalized):
  • Let's combine a few common canonical tables:
    • erc20_transfers (grabbed from logs),
    • internal_value_transfers (extracted from traces),
    • rollup_batches (this one will include a row for each L2 batch, featuring columns like mode={blob|calldata}, blob_versioned_hash[], and commit_tx),
    • user_operations (thanks to ERC‑4337: includes sender, bundler, paymaster, userOpHash, gas, and status).
  • With the Substreams SQL sink, we can whip up these tables using proto→SQL mapping instead of those handwritten mappers. Check it out here: (forum.thegraph.com)
• Gold (marts):
  • Business insights for compliance and audits:
    • “Outstanding Stablecoins by Issuer/Token/Region”
    • “Sanctions Exposure and Historical Reviews”
    • “L2 Batch Health (blob vs calldata, lag, costs)”
  • Don’t forget to keep those surrogate keys (source_block_number, source_tx_hash, source_log_index) handy for tracking!
• Update/delete at rest:
  • If you’re aiming to stick to the “right-to-be-forgotten” rule or need to make some DAC8 corrections, you’re in for a treat! Modern lakehouse tables (like S3 Tables) now allow you to do row-level upserts and deletes through streaming. This makes it super easy to handle those reorganization rewrites. You can check it out here: (aws.amazon.com)

Serving & observability plane

• Query engines:
  • If you’re tackling high-QPS log analytics, ClickHouse is the way to go. For your operational APIs, PostgreSQL is a solid choice. And when it comes to handling those hefty batch jobs, Spark or Trino are definitely your top contenders.
  • Oh, and make sure you add a dbt layer! It’s super helpful for setting up tests--like row counts, null checks, and deduplication--keeping track of source freshness, and monitoring lineage.
• Check out these SLOs you might want to share with the business:
  • Freshness: “We aim for less than 2 minutes to safe; under 15 minutes for finalized on ETH L1; less than 5 minutes for the OP-Stack sequencer feed; and under 60 seconds for Solana slots.”
  • Completeness: “We guarantee 100% of blocks in the range with no gaps, plus event counts that line up perfectly with receipts.”
  • Accuracy: “We post weekly Merkle commitments of marts on-chain.” Feel free to run a quick Substreams job to create a rolling Merkle and anchor the root.
• Telemetry:
  • Consider using OpenTelemetry to give your indexers some serious instrumentation. This will help you pull resource attributes into your Prometheus labels, making it a breeze to whip up those RED dashboards. And it gets even better--you can easily connect your metrics with logs (thanks to Loki) and traces (using Tempo). If you want to dive deeper into this, check out the details over on grafana.com.

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Practical, concrete examples (that ship)

1) MiCA + DAC8 stablecoin dashboard (issuer or exchange)

• Regulatory ground truth:
  • Here’s the lowdown: MiCA Titles III and IV, focusing on stablecoins, are now in action. ESMA has directed National Competent Authorities (NCAs) to wrap up trading for those non-MiCA-compliant ARTs and EMTs by the end of Q1 2025. On top of that, DAC8 is on the horizon, which means crypto-asset service providers will need to start gathering and reporting user transaction data starting January 1, 2026. The first reports are expected to come in between January 1 and September 30, 2027. And we can't overlook DORA; its operational resilience rules are set to kick in on January 17, 2025. (esma.europa.eu)
• What to index:
  • Keep an eye out for ERC‑20 Transfer events related to your stablecoin contracts.
  • Don't forget to keep track of the mint and burn functions (just make sure you're ABI‑decoding them) and any custodial ledger bridges that come into play.
  • Also, think about indexing those on/off-chain attestations, like the ERC‑3643 identity events, if you're dealing with permissioned tokenized cash.
  • If you're working with L2 wrappers, definitely index rollup_batches so you can tie those L2 flows back to L1 data availability. (eips.ethereum.org)
• Gold marts are set to publish:
  • A daily update on outstanding balances (that’s the supply on L1 and L2 wrappers all reconciled);
  • EU-resident flow flags for DAC8 (this will just involve a join on custodian KYC region, and we'll keep it off-chain);
  • A snapshot of non-compliant stablecoin exposure by venue (we'll be checking the listing universe against ESMA guidance).
• SQL pattern (supply):

  SELECT
    block_date,
    token_address,
    SUM(CASE WHEN to_addr = ZERO_ADDR THEN -value ELSE 0 END) +
    SUM(CASE WHEN from_addr = ZERO_ADDR THEN  value ELSE 0 END) AS net_issuance
  FROM erc20_transfers
  WHERE token_address IN (…)
  GROUP BY 1,2;

2) OFAC sanctions screening and lookbacks that auditors like

• Ground truth:
  • OFAC just dropped some new guidance for the virtual currency world, and it’s pretty interesting. They’re now including virtual currency addresses as identifiers for Specially Designated Nationals (SDNs). They've also set up a cool Sanctions List Service (SLS) that gives you datasets in an easy-to-read format for machines. Here are a few best practices to keep in mind: always block those listed addresses, track wallet clusters (you know, the ones that are shared), and don’t forget to do some historic lookbacks when new addresses pop up. Check it out here: (ofac.treasury.gov)
• What to implement:
  • Make sure to keep a nightly snapshot of SLS and look for any newly added crypto addresses by comparing the changes.
  • Automate lookbacks on erc20_transfers, internal_value_transfers, and key L2 bridges for the last 365 days.
  • Pinpoint “shared wallet risk” by clustering addresses that exhibit similar deposit or withdrawal trends with the listed addresses (using heuristics, not rigid conclusions).
• Evidence trail:
  • Make sure to log detection query hashes, data snapshots, and case files for every hit. This way, you’ll be ready to handle any testing or audit requests that come your way.

3) OP Stack batch health (operations and compliance)

• Ground truth:
  • OP Stack batchers can easily flex between blobs and calldata, switching it up based on the fee markets. Operators should try to get their batches in during specific windows (around 5-6 hours or so) to avoid any messy sequencing-window issues. It's crucial to pay attention to the maximum channel duration, batch frequency, and DA mode. Check out the details here: (docs.optimism.io)
• Indexing targets:
  • Events and metadata from the L2 batch inbox contract (think mode, channel duration, and L1 fees);
  • Versioned hashes for blobs tied to batches, allowing us to retrieve DA payloads for forensic replays whenever necessary;
  • Keeping a "safe head" lag in place to ensure we meet our user-facing finality SLAs.
• Check out these example KPI tiles that could come in handy:
  • “% of batches posted as blobs (over the last 7 days)”
  • “Median posting delay compared to our policy”
  • “Blob gas cost vs calldata cost (modeled) for every batch”

4) ERC‑4337 smart‑account ops (platform and paymasters)

• Ground truth:
  • The production stacks are ready to roll with EntryPoint v0.7. Bundlers take the lead by collecting UserOps and then using handleOps() on EntryPoint. They also handle indexing UserOperation hashes, manage gas sponsorship, and keep an eye on reasons for failures (like simulateValidation) to catch any weird patterns and help out with chargebacks. For more info, check it out here.
• Indexing targets:
  • Events that come from EntryPoint, such as UserOperationEvent, plus their matching receipts;
  • Paymaster costs sorted out by dApp or campaign;
  • Info about bundler identity and how latency changes.
• Practical checks:
  • Set up an alert to notify you if the UserOp failure rate exceeds the threshold for any campaign each day;
  • Monitor the packed and unpacked userOp schema versions in the logs as you transition from v0.6 to v0.7.

5) Solana DeFi risk monitor with Geyser

• Ground truth:
  • Seasoned indexers are tapping into Geyser plugins to send data over to Kafka or RabbitMQ, and they’re getting those program allowlists up and running. Plus, they're ramping up the producer buffers to prevent any data drops and ensuring that slot rollbacks are managed without a hitch. The latest updates have seriously boosted plugin logging and made it easier to see what's going on operationally. Take a look here: (github.com)
• Implementation Overview:
  • Start up the validator or hook into RPC using Geyser;
  • Geyser pushes data to a Kafka topic for each program (like the Token Program, Orca, or Raydium);
  • Consumers grab those account updates and convert them into spl_token_balances tables;
  • Set up alerts for events like “pool imbalance” and “sudden mint”.

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Emerging best practices (2025 edition)

• If you're getting into serious tracing, Reth or Erigon could be your best bets. Some impressive benchmarks show they really outperform the older stacks when it comes to RPC and trace throughput. Just remember to link this to your SLOs--like, for example, trying to “trace 1M tx/day within 2 hours.” Check this out for more info: (chainstack.com)
• Consider blob data as a crucial resource. Keep a rolling blob archive for over 18 days in Parquet format and set up “rollup_batches” that link back to versioned hashes. This method simplifies data reconstruction and helps with post-incident investigations. (eips.ethereum.org)
• Check out Substreams for transformations that are reusable and easy to audit. You can package your chain-agnostic modules (.spkg), push them to SQL/Parquet sinks through code generation, and take advantage of “Foundational Stores” with time travel for those backfills and restatements. (forum.thegraph.com)
• Get everything rolling with OpenTelemetry. Pump those resource attributes into Prometheus to make your dashboarding way smoother. Don’t forget to connect your logs (Loki) and traces (Tempo) so that your incident reports have solid span-level evidence of data freshness and accuracy. You can dive into more details here: (grafana.com)
• It’s important to understand the difference between “safe” and “finalized” data products. Product teams can tap into near-real-time “safe” marts, but when it comes to compliance extracts and financial statements, they should exclusively use “finalized” partitions. (ethereum.org)
• Stay aware of any delays with public datasets. BigQuery’s crypto datasets are fantastic for validation and exploring historical research, but they can occasionally lag behind (like that Solana dataset in 2025). So, it’s smart to set up your own primary pipeline. (check it out here)

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Compliance alignment checklist (EU/US)

• MiCA (EU):
  • Make sure you keep track of all the EMT/ART tokens you’re dealing with. After Q1 2025, it’s a no-go for trading any non-compliant stablecoins in the EU, so stay sharp! You’ll also want to document your controls. And hey, don’t forget to link your whitepapers and approvals in your metadata. Check out more details here.
• DAC8 (EU):
  • Starting from January 1, 2026, you'll need to get your act together when it comes to collecting data on crypto transactions for folks living in the EU. This means you’ll have to figure out where your users are based, set up some solid processes to gather year-end data, and keep those records tidy according to retention schedules. And hey, don’t forget to gear up for your 2026 filing - it’s due by September 30, 2027. Want more info? Check it out here.
• DORA (EU):
  • When it comes to your data pipeline incidents, be sure to share the nitty-gritty details--think severity/flow, recovery time objectives (RTO), and recovery point objectives (RPO). It’s also a good idea to keep an updated list of your third-party providers close by. And hey, don’t forget to run those regular resilience tests! Make sure your incident notifications are updated to match the new templates and timelines. (mondaq.com)
• OFAC (US):
  • Integrate OFAC SLS feeds; take a look at the listed addresses; perform lookbacks when new addresses appear; maintain records; document heuristics for “shared wallets” and figure out how to manage them. (home.treasury.gov)
• FinCEN (US):
  • Stay alert to how you're interacting with those CVC mixing types. If the 2023 NPRM gets the green light, you’ll have to get ready for some new recordkeeping and reporting guidelines for mixer transactions. Right now, the focus is on activating SAR instruments and identifying those key typologies. Check it out here: (fincen.gov)

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Concrete schemas, configs, and runbooks

• Basic “rollup_batches” schema for ETH L2:
  • l1_block_number BIGINT
  • l2_chain_id INT
  • batch_tx_hash BYTES(32)
  • mode ENUM('blob','calldata')
  • blob_versioned_hashes ARRAY
  • data_gas_used BIGINT
  • posted_at TIMESTAMP
  • safe_at TIMESTAMP
  • finalized_at TIMESTAMP
• Erigon Trace Enablement:

  erigon --http --http.api=eth,erigon,debug,trace,txpool \
         --private.api.addr=127.0.0.1:9090
  rpcdaemon --http.api=eth,erigon,debug,trace,txpool --datadir=/data/erigon

  (GitHub - Erigon)

• OP Stack batcher policy (default settings):
  • OP_BATCHER_DATA_AVAILABILITY_TYPE=auto
  • OP_BATCHER_MAX_CHANNEL_DURATION=1500 (which is roughly 5 hours when you consider L1 blocks at 12 seconds each)
  • Let’s make sure to set up an alert for when the channel duration exceeds 6 hours or gets close to the sequencing window buffer. You can find more details here: (docs.optimism.io)
• Solana Geyser Kafka plugin:
  • Make sure to set up program_allowlist for the key programs, crank up queue.buffering.max.messages|kbytes, and opt for batch inserts on the consumer side. Check it out on GitHub!

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Build vs. buy: when to choose which

• Choose Substreams/Firehose if:
  • You need those cross-chain, reusable transformations that have been audited, and you're also after some cool time travel and backfill features. Plus, if streaming directly into SQL or Parquet sinks sounds appealing to you, this is definitely the route to take! (forum.thegraph.com)
• Use in-house Erigon/Reth:
  • You really need to run those forensic-grade traces, handle custom debugging, and keep those low-latency pipelines up and running all within your own security framework. If that’s not an option, then make sure you have some strong deterministic internal transfer accounting sorted out.
• Take advantage of BigQuery public datasets:
  • These are awesome for diving into historical research, playing around with KPI queries, and double-checking your calculations. Just remember, they shouldn’t be your main source for real-time data--stay alert for any delays specific to the chain. (discuss.google.dev)

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How 7Block Labs can help

In our architecture, we take care of everything from A to Z. We customize solutions for clients like Reth and Erigon, set up blob archiving, and dive into Substreams modules. Plus, we build those Geyser-to-Kafka Solana pipelines that make everything flow smoothly.

When it comes to designing lakehouse schemas, we're all about Iceberg and Delta. We run dbt transformations with data tests included, and we make sure to back everything up with SLOs supported by Grafana.

On the compliance side, we whip up marts that are all set for MiCA, DAC8, and DORA compliance, and don’t forget about our OFAC and FinCEN screening playbooks! And of course, we provide solid evidence retention, lookback processes, and auditor-friendly runbooks to keep everything neat and tidy!

If you're curious about the smallest thing you can actually ship in 60-90 days, I've got a handy plan to kick things off:

• Get Reth or Erigon running along with Substreams for your top two chains and one Layer 2.
• Shift Parquet to a lakehouse, and model ERC‑20/4337/rollup_batches as Silver.
• Set up three Gold marts: one for stablecoin outstanding, another for sanctions lookbacks, and the last for monitoring L2 batch health.
• Kick things off with OpenTelemetry and RED dashboards, and make sure to publish your SLOs.

From there, start boosting your chain coverage and make sure to include customized regulatory reports for every region. Just remember, your indexing base is geared towards what to expect in 2025.

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References

• EIP‑4844 blobs (think of them as consensus sidecars) have a retention period of about 18 days. Learn more here.
• Pectra mainnet is rolling out an EIP‑7691 blob capacity increase, and we have the scoop on the activation time. Check out the details.
• If you're into OP Stack, the batcher policies and blob/call-data switching details are waiting for you. Dive into the docs.
• Don't miss out on the ERC‑4337 EntryPoint updates, including bundlers, versions, and providers now backing v0.7. Find out more.
• Solana Geyser plugins are getting some neat updates with Kafka, selector enhancements, and logging improvements. Explore the GitHub repo.
• We've got the latest on CometBFT/Cosmos's event indexing patterns. Read the full guide.
• There's a conversation happening about the lag in BigQuery crypto datasets, especially with Solana in 2025. See the discussion here.
• Need info on OFAC SLS and crypto address screening? We've got you covered. Check the press release.
• FinCEN has proposed a new CVC mixer rule under Section 311. Get the details.
• Curious about DORA's application date and the implementing regulations? Read more on Mondaq.
• Substreams have some exciting upgrades lined up, including SQL/Parquet mapping, Foundational Stores, and RPC v3. Check out the update.
• Reth/Erigon are stepping up with trace APIs and performance boosts. Find the API info here.
• JSON‑RPC is introducing “safe/finalized” tags and tweaking post‑Merge semantics. Discover more.