# Metropolis

Published articles for Metropolis.

This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles.

## Build a Multi-Camera 3D Tracking Application with NVIDIA DeepStream 9.1 Skills

DevFeed: [Build a Multi-Camera 3D Tracking Application with NVIDIA DeepStream 9.1 Skills](<https://devfeed.tech/articles/build-a-multi-camera-3d-tracking-application-with-nvidia-deepstream-9-1-skills-6766.md>)

Original publisher: [Read original article](<https://developer.nvidia.com/blog/build-a-multi-camera-3d-tracking-application-with-nvidia-deepstream-9-1-skills/>)

Author: Elizabeth Goodman

Published: 2026-07-15T23:00:00Z

Content type: tutorial

Language: en

Sources: [NVIDIA Developer](<https://devfeed.tech/sources/nvidia-developer.md>), [NVIDIA Technical Blog](<https://devfeed.tech/sources/nvidia-technical-blog.md>)

Topics: [multi-camera tracking](<https://devfeed.tech/topics/multi-camera-tracking.md>), [Nvidia](<https://devfeed.tech/topics/nvidia.md>), [AI Development](<https://devfeed.tech/topics/ai-development.md>), [Jetson](<https://devfeed.tech/topics/jetson.md>), [GitHub](<https://devfeed.tech/topics/github.md>), [Open Source](<https://devfeed.tech/topics/open-source.md>), [real-time](<https://devfeed.tech/topics/real-time.md>)

Tags: [3d](<https://devfeed.tech/tags/3d.md>), [agentic](<https://devfeed.tech/tags/agentic.md>), [agentic-ai-generative-ai](<https://devfeed.tech/tags/agentic-ai-generative-ai.md>), [ai](<https://devfeed.tech/tags/ai.md>), [ai-development](<https://devfeed.tech/tags/ai-development.md>), [analytics](<https://devfeed.tech/tags/analytics.md>), [applications](<https://devfeed.tech/tags/applications.md>), [automation](<https://devfeed.tech/tags/automation.md>), [computer-vision-video-analytics](<https://devfeed.tech/tags/computer-vision-video-analytics.md>), [deepstream](<https://devfeed.tech/tags/deepstream.md>), [developers](<https://devfeed.tech/tags/developers.md>), [development](<https://devfeed.tech/tags/development.md>), [edge](<https://devfeed.tech/tags/edge.md>), [featured](<https://devfeed.tech/tags/featured.md>), [github](<https://devfeed.tech/tags/github.md>), [jetpack](<https://devfeed.tech/tags/jetpack.md>), [jetson](<https://devfeed.tech/tags/jetson.md>), [metropolis](<https://devfeed.tech/tags/metropolis.md>), [multi-camera-tracking](<https://devfeed.tech/tags/multi-camera-tracking.md>), [nvidia](<https://devfeed.tech/tags/nvidia.md>), [real-time](<https://devfeed.tech/tags/real-time.md>), [research](<https://devfeed.tech/tags/research.md>), [spaces](<https://devfeed.tech/tags/spaces.md>), [video](<https://devfeed.tech/tags/video.md>), [video-analytics](<https://devfeed.tech/tags/video-analytics.md>)

### AI overview

This article introduces NVIDIA DeepStream 9.1 capabilities for building multi-camera 3D tracking applications. It explains how AutoMagicCalib and Multi-View 3D Tracking combine detections from auto-calibrated cameras in a shared 3D coordinate system, maintaining consistent object IDs across views. It also highlights agentic skills, JetPack support for Jetson edge platforms, and open-source reference implementations.

### Source excerpt

Developers building video analytics applications across large spaces must track the same object as it moves between camera views. Single-camera 2D tracking...

## Clean Chat Example App with Jetpack Compose

DevFeed: [Clean Chat Example App with Jetpack Compose](<https://devfeed.tech/articles/clean-chat-example-app-with-jetpack-compose-27036.md>)

Original publisher: [Read original article](<https://getstream.io/blog/jetpack-compose-clean-chat-example/>)

Author: Márton Braun

Published: 2021-06-08T18:00:00Z

Content type: tutorial

Language: en

Sources: [zsmb.co](<https://devfeed.tech/sources/zsmb-co.md>)

Topics: [Jetpack Compose](<https://devfeed.tech/topics/jetpack-compose.md>), [Compose](<https://devfeed.tech/topics/compose.md>), [ui](<https://devfeed.tech/topics/ui.md>), [Android](<https://devfeed.tech/topics/android.md>), [Code](<https://devfeed.tech/topics/code.md>), [Font](<https://devfeed.tech/topics/font.md>), [Metropolis](<https://devfeed.tech/topics/metropolis.md>)

Tags: [android](<https://devfeed.tech/tags/android.md>), [app](<https://devfeed.tech/tags/app.md>), [build](<https://devfeed.tech/tags/build.md>), [code](<https://devfeed.tech/tags/code.md>), [color](<https://devfeed.tech/tags/color.md>), [compiler](<https://devfeed.tech/tags/compiler.md>), [compose](<https://devfeed.tech/tags/compose.md>), [jetpack-compose](<https://devfeed.tech/tags/jetpack-compose.md>), [metropolis](<https://devfeed.tech/tags/metropolis.md>), [palette](<https://devfeed.tech/tags/palette.md>), [resource](<https://devfeed.tech/tags/resource.md>), [tutorial](<https://devfeed.tech/tags/tutorial.md>), [ui](<https://devfeed.tech/tags/ui.md>)

### AI overview

This tutorial reviews a Jetpack Compose chat UI sample, covering color management, custom Metropolis fonts, theme configuration, composable functions, and compiler optimizations.

### Source excerpt

Jetpack Compose makes it easy to build beautiful UI. Check out this Chat UI sample, and learn some exciting bits of Compose along the way!

## Ethereum Metropolis and Byzantium Development Roundup

DevFeed: [Ethereum Metropolis and Byzantium Development Roundup](<https://devfeed.tech/articles/roundup-6-16812.md>)

Original publisher: [Read original article](<https://blog.ethereum.org/en/2017/10/09/roundup-6>)

Author: Ethereum Foundation

Published: 2017-10-09T09:55:53Z

Content type: news

Language: en

Sources: [Ethereum Foundation Blog](<https://devfeed.tech/sources/ethereum-foundation-blog.md>)

Topics: [Ethereum](<https://devfeed.tech/topics/ethereum.md>), [Metropolis](<https://devfeed.tech/topics/metropolis.md>), [resharper](<https://devfeed.tech/topics/resharper.md>), [rust refactoring](<https://devfeed.tech/topics/rust-refactoring.md>), [Algorithms, Complexity](<https://devfeed.tech/topics/algorithms-complexity.md>)

Tags: [code](<https://devfeed.tech/tags/code.md>), [cryptographic](<https://devfeed.tech/tags/cryptographic.md>), [deadlock](<https://devfeed.tech/tags/deadlock.md>), [documentation](<https://devfeed.tech/tags/documentation.md>), [ethereum](<https://devfeed.tech/tags/ethereum.md>), [features](<https://devfeed.tech/tags/features.md>), [metropolis](<https://devfeed.tech/tags/metropolis.md>), [new-features](<https://devfeed.tech/tags/new-features.md>), [python](<https://devfeed.tech/tags/python.md>), [race-condition](<https://devfeed.tech/tags/race-condition.md>), [research-development](<https://devfeed.tech/tags/research-development.md>), [sharding](<https://devfeed.tech/tags/sharding.md>), [unit-test](<https://devfeed.tech/tags/unit-test.md>), [warp](<https://devfeed.tech/tags/warp.md>)

### AI overview

An Ethereum development roundup reports progress on the Metropolis and Byzantium fork, including testnet success, a projected mainnet block, new opcodes and cryptographic precompiles. It also covers Casper, sharding, client updates, synchronization, refactoring, bug fixes, and testing improvements.

### Source excerpt

Metropolis is finally (almost) here! The fork for Byzantium, the first and larger part of Metropolis, succeeded on the testnet over two weeks ago, and the likely date for the fork on the mainnet has been set to block 4.37 million, which is expected to be on Oct 17. New features...

## Ethereum Development Roundup #5: Metropolis, Casper, Sharding, and Client Updates

DevFeed: [Ethereum Development Roundup #5: Metropolis, Casper, Sharding, and Client Updates](<https://devfeed.tech/articles/roundup-5-16810.md>)

Original publisher: [Read original article](<https://blog.ethereum.org/en/2017/08/23/roundup-5>)

Author: Ethereum Foundation

Published: 2017-08-23T12:34:51Z

Content type: news

Language: en

Sources: [Ethereum Foundation Blog](<https://devfeed.tech/sources/ethereum-foundation-blog.md>)

Topics: [Metropolis](<https://devfeed.tech/topics/metropolis.md>), [Ethereum](<https://devfeed.tech/topics/ethereum.md>), [Development](<https://devfeed.tech/topics/development.md>), [Testing](<https://devfeed.tech/topics/testing.md>), [Python](<https://devfeed.tech/topics/python.md>)

Tags: [code-quality](<https://devfeed.tech/tags/code-quality.md>), [dev](<https://devfeed.tech/tags/dev.md>), [development](<https://devfeed.tech/tags/development.md>), [ethereum](<https://devfeed.tech/tags/ethereum.md>), [hardware](<https://devfeed.tech/tags/hardware.md>), [metropolis](<https://devfeed.tech/tags/metropolis.md>), [python](<https://devfeed.tech/tags/python.md>), [research-development](<https://devfeed.tech/tags/research-development.md>), [testing](<https://devfeed.tech/tags/testing.md>)

### AI overview

This Ethereum development roundup reports progress toward the Metropolis launch, including the Byzantium and Constantinople split and ongoing EIP, testing, and client work. It also covers Casper and sharding research, a testing language, the Plasma whitepaper, network stability, database improvements, hardware-wallet support, and other client updates.

### Source excerpt

Development has steadily continued over the last month and a half as we approach the launch of Metropolis. Over a series of core dev calls over the last few months, we have specified and finalized the EIPs for...

## Ethereum Q2 Roundup: Network Growth, Scalability Work, and Metropolis Testing

DevFeed: [Ethereum Q2 Roundup: Network Growth, Scalability Work, and Metropolis Testing](<https://devfeed.tech/articles/roundup-q2-16808.md>)

Original publisher: [Read original article](<https://blog.ethereum.org/en/2017/07/08/roundup-q2>)

Author: Vitalik Buterin

Published: 2017-07-08T02:03:25Z

Content type: article

Language: en

Sources: [Ethereum Foundation Blog](<https://devfeed.tech/sources/ethereum-foundation-blog.md>)

Topics: [Ethereum](<https://devfeed.tech/topics/ethereum.md>), [Network](<https://devfeed.tech/topics/network.md>), [Scalability](<https://devfeed.tech/topics/scalability.md>), [Transactions](<https://devfeed.tech/topics/transactions.md>), [Testing](<https://devfeed.tech/topics/testing.md>)

Tags: [cache](<https://devfeed.tech/tags/cache.md>), [ethereum](<https://devfeed.tech/tags/ethereum.md>), [metropolis](<https://devfeed.tech/tags/metropolis.md>), [network](<https://devfeed.tech/tags/network.md>), [research-development](<https://devfeed.tech/tags/research-development.md>), [scalability](<https://devfeed.tech/tags/scalability.md>), [testing](<https://devfeed.tech/tags/testing.md>), [transactions](<https://devfeed.tech/tags/transactions.md>)

### AI overview

An Ethereum Q2 roundup reports rapid network usage growth, increased capacity through a higher gas limit, and work on efficiency and long-term scalability. It also covers research into Casper and sharding, Metropolis testing, and Mist wallet development focused on synchronization and account key management.

### Source excerpt

Thanks to all the developers and team leads who contributed to the sections on their projects In the last month and a half, the Ethereum network went through a rapid growth in usage, to the point that it now processes as many transactions per second as Bitcoin. To accommodate...

## Ethereum Development Roundup: Metropolis Progress and Side-Project Updates

DevFeed: [Ethereum Development Roundup: Metropolis Progress and Side-Project Updates](<https://devfeed.tech/articles/roundup-round-iii-16807.md>)

Original publisher: [Read original article](<https://blog.ethereum.org/en/2017/05/24/roundup-round-iii>)

Author: Vitalik Buterin

Published: 2017-05-24T17:04:21Z

Content type: news

Language: en

Sources: [Ethereum Foundation Blog](<https://devfeed.tech/sources/ethereum-foundation-blog.md>)

Topics: [Ethereum](<https://devfeed.tech/topics/ethereum.md>), [Metropolis](<https://devfeed.tech/topics/metropolis.md>), [Blockchain](<https://devfeed.tech/topics/blockchain.md>), [C++](<https://devfeed.tech/topics/c-plus-plus.md>), [Python](<https://devfeed.tech/topics/python.md>), [Ethereum Name Service (ENS)](<https://devfeed.tech/topics/ens.md>), [Whisper](<https://devfeed.tech/topics/whisper.md>), [API](<https://devfeed.tech/topics/api.md>), [Remote Procedure Call (RPC)](<https://devfeed.tech/topics/rpc.md>)

Tags: [api](<https://devfeed.tech/tags/api.md>), [blockchain](<https://devfeed.tech/tags/blockchain.md>), [c-plus-plus](<https://devfeed.tech/tags/c-plus-plus.md>), [development](<https://devfeed.tech/tags/development.md>), [ethereum](<https://devfeed.tech/tags/ethereum.md>), [metropolis](<https://devfeed.tech/tags/metropolis.md>), [python](<https://devfeed.tech/tags/python.md>), [research-development](<https://devfeed.tech/tags/research-development.md>), [rpc](<https://devfeed.tech/tags/rpc.md>), [whisper](<https://devfeed.tech/tags/whisper.md>)

### AI overview

This roundup reports progress on Ethereum's Metropolis roadmap, including implemented EIPs, client testing, and the lack of a finalized release date. It also covers blockchain activity, ENS auctions, Whisper API work, and Swarm improvements.

### Source excerpt

Over the last month and a half we saw vigorous ongoing research and development on all sides of the Ethereum roadmap, and progress is rapidly starting to translate into real results that can be run and verified inside of an Ethereum client. On Metropolis: Agendas for core dev...

## Ethereum Dev Roundup: Q1

DevFeed: [Ethereum Dev Roundup: Q1](<https://devfeed.tech/articles/ethereum-dev-roundup-q1-16803.md>)

Original publisher: [Read original article](<https://blog.ethereum.org/en/2017/04/01/ethereum-dev-roundup-q1>)

Author: Vitalik Buterin

Published: 2017-04-01T02:55:28Z

Content type: opinion

Language: en

Sources: [Ethereum Foundation Blog](<https://devfeed.tech/sources/ethereum-foundation-blog.md>)

Topics: [Ethereum](<https://devfeed.tech/topics/ethereum.md>), [Development](<https://devfeed.tech/topics/development.md>), [Algorithms](<https://devfeed.tech/topics/algorithms.md>), [Formal verification](<https://devfeed.tech/topics/formal-verification.md>), [zero-knowledge](<https://devfeed.tech/topics/zero-knowledge.md>)

Tags: [algorithms](<https://devfeed.tech/tags/algorithms.md>), [attacks](<https://devfeed.tech/tags/attacks.md>), [consensus](<https://devfeed.tech/tags/consensus.md>), [dev](<https://devfeed.tech/tags/dev.md>), [ethereum](<https://devfeed.tech/tags/ethereum.md>), [formal-verification](<https://devfeed.tech/tags/formal-verification.md>), [immutability](<https://devfeed.tech/tags/immutability.md>), [implementation](<https://devfeed.tech/tags/implementation.md>), [metropolis](<https://devfeed.tech/tags/metropolis.md>), [privacy](<https://devfeed.tech/tags/privacy.md>), [proof-of-authority](<https://devfeed.tech/tags/proof-of-authority.md>), [protocol](<https://devfeed.tech/tags/protocol.md>), [research](<https://devfeed.tech/tags/research.md>), [research-development](<https://devfeed.tech/tags/research-development.md>), [state](<https://devfeed.tech/tags/state.md>), [verification](<https://devfeed.tech/tags/verification.md>), [zero-knowledge](<https://devfeed.tech/tags/zero-knowledge.md>)

### AI overview

An Ethereum development roundup discusses research progress in consensus algorithms, privacy, zero-knowledge proofs, and formal verification, alongside proposed changes involving proof of authority, transaction reversion, Metropolis, and protocol rules.

### Source excerpt

The last one and a half months have seen great progress for Ethereum research, and we are excited that the protocol is moving closer and closer to the point where it is ready for mainstream adoption. Progress on consensus algorithms, privacy, zero knowledge proofs and formal verification is happening at...

## Ethereum R&D Roundup: Valentine's Day Edition

DevFeed: [Ethereum R&D Roundup: Valentine's Day Edition](<https://devfeed.tech/articles/ethereum-r-d-roundup-valentine-s-day-edition-16801.md>)

Original publisher: [Read original article](<https://blog.ethereum.org/en/2017/02/14/ethereum-rnd-roundup-valentines-day-edition>)

Author: Vitalik Buterin

Published: 2017-02-14T19:27:28Z

Content type: article

Language: en

Sources: [Ethereum Foundation Blog](<https://devfeed.tech/sources/ethereum-foundation-blog.md>)

Topics: [Ethereum](<https://devfeed.tech/topics/ethereum.md>), [Metropolis](<https://devfeed.tech/topics/metropolis.md>), [Development](<https://devfeed.tech/topics/development.md>), [Programming](<https://devfeed.tech/topics/programming.md>), [Security](<https://devfeed.tech/topics/security.md>)

Tags: [compiler](<https://devfeed.tech/tags/compiler.md>), [developer](<https://devfeed.tech/tags/developer.md>), [development](<https://devfeed.tech/tags/development.md>), [ethereum](<https://devfeed.tech/tags/ethereum.md>), [metropolis](<https://devfeed.tech/tags/metropolis.md>), [research-development](<https://devfeed.tech/tags/research-development.md>), [security](<https://devfeed.tech/tags/security.md>)

### AI overview

This Ethereum R&D roundup reports progress by the core development and research teams, including work on the Metropolis hard fork, zk-SNARKs, EIPs, Mist, Swarm, ENS, Solidity, Viper, Remix, and cpp-ethereum.

### Source excerpt

During the last month and a half, the Ethereum core development and research teams have been building upon the progress made in the last year, and with the specter of last year's security issues now well behind us, work has begun in full force on implementing the Metropolis hard fork....

## Ethereum Research Update

DevFeed: [Ethereum Research Update](<https://devfeed.tech/articles/ethereum-research-update-16792.md>)

Original publisher: [Read original article](<https://blog.ethereum.org/en/2016/12/04/ethereum-research-update>)

Author: Vitalik Buterin

Published: 2016-12-04T11:27:47Z

Content type: article

Language: en

Sources: [Ethereum Foundation Blog](<https://devfeed.tech/sources/ethereum-foundation-blog.md>)

Topics: [Ethereum](<https://devfeed.tech/topics/ethereum.md>), [Network](<https://devfeed.tech/topics/network.md>), [DDoS](<https://devfeed.tech/topics/ddos.md>), [Metropolis](<https://devfeed.tech/topics/metropolis.md>), [Protocol (disambiguation)](<https://devfeed.tech/topics/protocol.md>), [Solidity](<https://devfeed.tech/topics/solidity.md>), [C++](<https://devfeed.tech/topics/c-plus-plus.md>), [Go](<https://devfeed.tech/topics/go.md>), [Cryptography](<https://devfeed.tech/topics/cryptography.md>)

Tags: [attacks](<https://devfeed.tech/tags/attacks.md>), [c-plus-plus](<https://devfeed.tech/tags/c-plus-plus.md>), [development](<https://devfeed.tech/tags/development.md>), [ethereum](<https://devfeed.tech/tags/ethereum.md>), [fork](<https://devfeed.tech/tags/fork.md>), [go](<https://devfeed.tech/tags/go.md>), [metropolis](<https://devfeed.tech/tags/metropolis.md>), [network](<https://devfeed.tech/tags/network.md>), [protocol](<https://devfeed.tech/tags/protocol.md>), [research](<https://devfeed.tech/tags/research.md>), [research-development](<https://devfeed.tech/tags/research-development.md>), [security](<https://devfeed.tech/tags/security.md>)

### AI overview

Ethereum's fourth hard fork, Spurious Dragon, and the related state-clearing process completed the planned response to recent denial-of-service attacks. The update also describes client-development progress and planned protocol improvements for the Metropolis hard fork.

### Source excerpt

This week marks the completion of our fourth hard fork, Spurious Dragon, and the subsequent state clearing process, the final steps in the two-hard-fork solution to the recent Ethereum denial of service attacks that slowed down the network in September and October. Gas limits are in the proce...

## Transaction spam attack: Next Steps

DevFeed: [Transaction spam attack: Next Steps](<https://devfeed.tech/articles/transaction-spam-attack-next-steps-16781.md>)

Original publisher: [Read original article](<https://blog.ethereum.org/en/2016/09/22/transaction-spam-attack-next-steps>)

Author: Vitalik Buterin

Published: 2016-09-22T21:31:35Z

Content type: news

Language: en

Sources: [Ethereum Foundation Blog](<https://devfeed.tech/sources/ethereum-foundation-blog.md>)

Topics: [Network](<https://devfeed.tech/topics/network.md>), [Cache](<https://devfeed.tech/topics/cache.md>), [Go](<https://devfeed.tech/topics/go.md>), [Protocol (disambiguation)](<https://devfeed.tech/topics/protocol.md>), [Metropolis](<https://devfeed.tech/topics/metropolis.md>)

Tags: [attacks](<https://devfeed.tech/tags/attacks.md>), [cache](<https://devfeed.tech/tags/cache.md>), [go](<https://devfeed.tech/tags/go.md>), [io](<https://devfeed.tech/tags/io.md>), [metropolis](<https://devfeed.tech/tags/metropolis.md>), [network](<https://devfeed.tech/tags/network.md>), [protocol](<https://devfeed.tech/tags/protocol.md>), [protocol-announcements](<https://devfeed.tech/tags/protocol-announcements.md>)

### AI overview

An Ethereum transaction spam attack repeatedly invoked the EXTCODESIZE opcode, slowing block validation and reducing block creation rates without causing a consensus failure or full network halt. The article describes short-term configuration changes and longer-term client, caching, and protocol mitigations.

### Source excerpt

Today the network was attacked by a transaction spam attack that repeatedly called the EXTCODESIZE opcode (see trace sample here), thereby creating blocks that take up to 20-60 seconds to validate due to the 50,000 disk fetches needed to process the transaction. The result of this was a ~2-3x reduction...