{"id":18444,"date":"2026-03-19T07:06:33","date_gmt":"2026-03-19T07:06:33","guid":{"rendered":"https:\/\/cryptoted.net\/index.php\/2026\/03\/19\/eth2-interop-in-review-ethereum-foundation-blog\/"},"modified":"2026-03-19T07:06:33","modified_gmt":"2026-03-19T07:06:33","slug":"eth2-interop-in-review-ethereum-foundation-blog","status":"publish","type":"post","link":"https:\/\/cryptoted.net\/index.php\/2026\/03\/19\/eth2-interop-in-review-ethereum-foundation-blog\/","title":{"rendered":"Eth2 Interop in Review | Ethereum Foundation Blog"},"content":{"rendered":"<p> <br \/>\n<\/p>\n<div id=\"\">\n<p class=\"chakra-text css-gi02ar\">Last week, seven of the eight Eth2 clients under active development succeeded in marking the major milestone of moving from single-client to multi-client testnets at the &#8220;Interop Lock-in&#8221;. With this exciting success in Eth2 development, we wanted to reflect on how this point was reached and on what it means to the Ethereum network and ecosystem.<\/p>\n<p class=\"chakra-text css-gi02ar\">Anyone following Ethereum over the past couple of years has likely become familiar with terms such as &#8220;Ethereum 2.0&#8221;, &#8220;Eth2&#8221;, or &#8220;Serenity&#8221;. Each of these refer to substantial upgrades slated for the Ethereum protocol that have been envisioned in some form since before the network went live in 2015.<\/p>\n<p class=\"chakra-text css-gi02ar\">In the early years of Ethereum, groundbreaking research was accomplished in parallel to the original chain (Eth1) launching, while the massive growth of the Ethereum community that followed aided the initial adoption of decentralized applications. Still, the road from these early breakthroughs to a highly decentralized, yet scalable proof-of-stake blockchain has been long. Over the past 18 months though, research has finally stablized into a cohesive and complete vision for the coming major upgrades known as Eth2.<\/p>\n<p class=\"chakra-text css-gi02ar\">As research moved into specifications toward the end of 2018, <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/docs.ethhub.io\/ethereum-roadmap\/ethereum-2.0\/eth2.0-teams\/teams-building-eth2.0\/\">many teams<\/a> (client teams) from across the community stepped up to build out core implementations of the protocol (clients). Since then, there has been a dynamic play between specification and implementation. <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/github.com\/ethereum\/eth2.0-pm\/\">Fort-nightly calls<\/a> and a common <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/github.com\/ethereum\/eth2.0-specs\">spec repository<\/a> organize communication and the sharing of ideas, but client teams have primarily worked in relative isolation, building and testing their implementations of the protocol.<\/p>\n<p class=\"chakra-text css-gi02ar\">While the spec was a moving target, clients could only dig so deep into interoperability and optimizations, but once the Phase 0 specification of Eth2 was deemed <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/github.com\/ethereum\/eth2.0-specs\/releases\/tag\/v0.8.0\">&#8220;frozen&#8221;<\/a> on July 1, 2019, clients made tremendous progress and began to take concrete steps toward production.<\/p>\n<h2 class=\"chakra-heading group css-1kpzc4q\" id=\"interop\" data-group=\"true\"><a class=\"chakra-link css-128fqrf\" aria-label=\"interop permalink\" href=\"#interop\"><svg viewbox=\"0 0 24 24\" focusable=\"false\" class=\"chakra-icon css-173jpr1\"><g fill=\"currentColor\"><path d=\"M10.458,18.374,7.721,21.11a2.853,2.853,0,0,1-3.942,0l-.892-.891a2.787,2.787,0,0,1,0-3.941l5.8-5.8a2.789,2.789,0,0,1,3.942,0l.893.892A1,1,0,0,0,14.94,9.952l-.893-.892a4.791,4.791,0,0,0-6.771,0l-5.8,5.8a4.787,4.787,0,0,0,0,6.77l.892.891a4.785,4.785,0,0,0,6.771,0l2.736-2.735a1,1,0,1,0-1.414-1.415Z\"\/><path d=\"M22.526,2.363l-.892-.892a4.8,4.8,0,0,0-6.77,0l-2.905,2.9a1,1,0,0,0,1.414,1.414l2.9-2.9a2.79,2.79,0,0,1,3.941,0l.893.893a2.786,2.786,0,0,1,0,3.942l-5.8,5.8a2.769,2.769,0,0,1-1.971.817h0a2.766,2.766,0,0,1-1.969-.816,1,1,0,1,0-1.415,1.412,4.751,4.751,0,0,0,3.384,1.4h0a4.752,4.752,0,0,0,3.385-1.4l5.8-5.8a4.786,4.786,0,0,0,0-6.771Z\"\/><\/g><\/svg><\/a>Interop<\/h2>\n<p class=\"chakra-text css-gi02ar\">Joseph Delong from <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/pegasys.tech\/\">Pegasys<\/a> had the crazy idea of gathering members from each of the client engineering teams in a remote location for a week of interoperability work. The event was deemed the &#8220;Interop Lock-in&#8221; or as it was generally referred &#8212; &#8220;Interop&#8221;. With the spec freeze in sight and De<strong>v<\/strong>con on the horizon, Interop in September was an opportunity have all of these stakeholders work through initial interop-issues in person.<\/p>\n<p class=\"chakra-text css-gi02ar\">The <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/github.com\/ethereum\/eth2.0-pm\/blob\/master\/interop\/lockin\/goals-exercises.md\">primary purpose<\/a> of the event was to have each participating client to achieve pair-wise interoperability with each other client in small test networks &#8212; <span class=\"chakra-text css-ons8vw\">Lighthouse  Artemis<\/span>, <span class=\"chakra-text css-ons8vw\">Lodestar  Lighthouse<\/span>, <span class=\"chakra-text css-ons8vw\">Lodestar  Artemis<\/span>, etc.<\/p>\n<p class=\"chakra-text css-gi02ar\">Participating client teams included:<\/p>\n<p class=\"chakra-text css-gi02ar\">Additional goals involved testing (1) larger networks in both node count and (2) validator count, (3) networks with 3+ clients, (4) enhancing tooling for monitoring and debugging Eth2 networks, and (5) other fun things like getting raspberry pis running and building fork visualizers.<\/p>\n<p class=\"chakra-text css-gi02ar\">Leading up to the event, some goals seemed like a stretch, but teams worked diligently until the deadline and achieved amazing progress. By the end of the week, client teams far exceeded original expectations of having a few pair-wise networks, instead completing the entire pair-wise tests, building a small network of <em class=\"chakra-text css-0\">all<\/em> 7 participating clients, and more.<\/p>\n<p class=\"chakra-text css-gi02ar\">The following represent a glimpse into the highlights of the client successes, but is certainly not exhaustive:<\/p>\n<h3 class=\"chakra-heading group css-xuzltg\" id=\"multi-client-testnets\" data-group=\"true\"><a class=\"chakra-link css-128fqrf\" aria-label=\"multi client testnets permalink\" href=\"#multi-client-testnets\"><svg viewbox=\"0 0 24 24\" focusable=\"false\" class=\"chakra-icon css-173jpr1\"><g fill=\"currentColor\"><path d=\"M10.458,18.374,7.721,21.11a2.853,2.853,0,0,1-3.942,0l-.892-.891a2.787,2.787,0,0,1,0-3.941l5.8-5.8a2.789,2.789,0,0,1,3.942,0l.893.892A1,1,0,0,0,14.94,9.952l-.893-.892a4.791,4.791,0,0,0-6.771,0l-5.8,5.8a4.787,4.787,0,0,0,0,6.77l.892.891a4.785,4.785,0,0,0,6.771,0l2.736-2.735a1,1,0,1,0-1.414-1.415Z\"\/><path d=\"M22.526,2.363l-.892-.892a4.8,4.8,0,0,0-6.77,0l-2.905,2.9a1,1,0,0,0,1.414,1.414l2.9-2.9a2.79,2.79,0,0,1,3.941,0l.893.893a2.786,2.786,0,0,1,0,3.942l-5.8,5.8a2.769,2.769,0,0,1-1.971.817h0a2.766,2.766,0,0,1-1.969-.816,1,1,0,1,0-1.415,1.412,4.751,4.751,0,0,0,3.384,1.4h0a4.752,4.752,0,0,0,3.385-1.4l5.8-5.8a4.786,4.786,0,0,0,0-6.771Z\"\/><\/g><\/svg><\/a>Multi-client testnets<\/h3>\n<p class=\"chakra-text css-gi02ar\"><img decoding=\"async\" alt=\"5-way eth2 testnet\" src=\"https:\/\/blog.ethereum.org\/images\/posts\/5-way-interop.jpeg\" class=\"chakra-image css-hw6q2r\"\/><\/p>\n<ul role=\"list\" class=\"css-1ars4k6\">\n<li class=\"css-0\">All 7 participating clients achieved <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/twitter.com\/paulhauner\/status\/1170952290469122048\">pair-wise interoperability<\/a>, and although an 8th, <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/github.com\/paritytech\/shasper\">Shasper<\/a>, was not able to be in attendence, they have <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/twitter.com\/sorpaas\/status\/1172350637847326722\">begun<\/a> to work through this milestone as well.<\/li>\n<li class=\"css-0\">Many larger testnets were formed between 3+ clients, 3+ nodes, and higher than minimal validator counts.<\/li>\n<li class=\"css-0\"><a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/twitter.com\/JonnyRhea\/status\/1172233598109442049\">All 7 clients<\/a> in attendence were successfully run on a single network.<\/li>\n<li class=\"css-0\">All participating languages&#8217; libp2p implementations are now interoperable after debugging some minor issues.<\/li>\n<\/ul>\n<h3 class=\"chakra-heading group css-xuzltg\" id=\"network-debugging-and-tools\" data-group=\"true\"><a class=\"chakra-link css-128fqrf\" aria-label=\"network debugging and tools permalink\" href=\"#network-debugging-and-tools\"><svg viewbox=\"0 0 24 24\" focusable=\"false\" class=\"chakra-icon css-173jpr1\"><g fill=\"currentColor\"><path d=\"M10.458,18.374,7.721,21.11a2.853,2.853,0,0,1-3.942,0l-.892-.891a2.787,2.787,0,0,1,0-3.941l5.8-5.8a2.789,2.789,0,0,1,3.942,0l.893.892A1,1,0,0,0,14.94,9.952l-.893-.892a4.791,4.791,0,0,0-6.771,0l-5.8,5.8a4.787,4.787,0,0,0,0,6.77l.892.891a4.785,4.785,0,0,0,6.771,0l2.736-2.735a1,1,0,1,0-1.414-1.415Z\"\/><path d=\"M22.526,2.363l-.892-.892a4.8,4.8,0,0,0-6.77,0l-2.905,2.9a1,1,0,0,0,1.414,1.414l2.9-2.9a2.79,2.79,0,0,1,3.941,0l.893.893a2.786,2.786,0,0,1,0,3.942l-5.8,5.8a2.769,2.769,0,0,1-1.971.817h0a2.766,2.766,0,0,1-1.969-.816,1,1,0,1,0-1.415,1.412,4.751,4.751,0,0,0,3.384,1.4h0a4.752,4.752,0,0,0,3.385-1.4l5.8-5.8a4.786,4.786,0,0,0,0-6.771Z\"\/><\/g><\/svg><\/a>Network debugging and tools<\/h3>\n<p class=\"chakra-text css-gi02ar\"><img decoding=\"async\" alt=\"Client metrics\" src=\"https:\/\/blog.ethereum.org\/images\/posts\/trinity-dashboard.png\" class=\"chakra-image css-hw6q2r\"\/><\/p>\n<ul role=\"list\" class=\"css-1ars4k6\">\n<li class=\"css-0\">Some <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/github.com\/djrtwo\/interop-test-cases\/\">consensus errors<\/a> between clients were identified, debugged, and recorded as portions of the state transition that require increased test coverage.<\/li>\n<li class=\"css-0\">Command line tools were built to better debug ssz objects and state transitions (<a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/github.com\/protolambda\/zcli\">zcli<\/a>, <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/github.com\/djrtwo\/pycli\">pycli<\/a>, and similar tools embedded within clients).<\/li>\n<li class=\"css-0\">Progress made on metrics dashboards, a fork visualizer, and other tools to better understand clients and networks<\/li>\n<li class=\"css-0\">Clients were packaged up into containers to perform large-scale network tests within the <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/whiteblock.io\/\">Whiteblock<\/a> genesis platform.<\/li>\n<\/ul>\n<h3 class=\"chakra-heading group css-xuzltg\" id=\"and-then-some\" data-group=\"true\"><a class=\"chakra-link css-128fqrf\" aria-label=\"and then some permalink\" href=\"#and-then-some\"><svg viewbox=\"0 0 24 24\" focusable=\"false\" class=\"chakra-icon css-173jpr1\"><g fill=\"currentColor\"><path d=\"M10.458,18.374,7.721,21.11a2.853,2.853,0,0,1-3.942,0l-.892-.891a2.787,2.787,0,0,1,0-3.941l5.8-5.8a2.789,2.789,0,0,1,3.942,0l.893.892A1,1,0,0,0,14.94,9.952l-.893-.892a4.791,4.791,0,0,0-6.771,0l-5.8,5.8a4.787,4.787,0,0,0,0,6.77l.892.891a4.785,4.785,0,0,0,6.771,0l2.736-2.735a1,1,0,1,0-1.414-1.415Z\"\/><path d=\"M22.526,2.363l-.892-.892a4.8,4.8,0,0,0-6.77,0l-2.905,2.9a1,1,0,0,0,1.414,1.414l2.9-2.9a2.79,2.79,0,0,1,3.941,0l.893.893a2.786,2.786,0,0,1,0,3.942l-5.8,5.8a2.769,2.769,0,0,1-1.971.817h0a2.766,2.766,0,0,1-1.969-.816,1,1,0,1,0-1.415,1.412,4.751,4.751,0,0,0,3.384,1.4h0a4.752,4.752,0,0,0,3.385-1.4l5.8-5.8a4.786,4.786,0,0,0,0-6.771Z\"\/><\/g><\/svg><\/a>And then some<\/h3>\n<p class=\"chakra-text css-gi02ar\"><img decoding=\"async\" alt=\"Eth2 on a pi\" src=\"https:\/\/blog.ethereum.org\/images\/posts\/eth2-pi.jpeg\" class=\"chakra-image css-hw6q2r\"\/><\/p>\n<ul role=\"list\" class=\"css-1ars4k6\">\n<li class=\"css-0\">Client teams served as eachother&#8217;s first alpha users resulting in extensive <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/github.com\/status-im\/nim-beacon-chain\/tree\/interop\/multinet\">build\/run scripts<\/a> and related documentation.<\/li>\n<li class=\"css-0\">Isolated load tests with Nimbus and Lighthouse handled 2000+ validators on a single machine paired with similarly full nodes over LAN.<\/li>\n<li class=\"css-0\">Multiple clients were built and tested on a <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/twitter.com\/jcksie\/status\/1171886857908609024\">small raspberry pi network<\/a>.<\/li>\n<\/ul>\n<h2 class=\"chakra-heading group css-1kpzc4q\" id=\"and-beyond\" data-group=\"true\"><a class=\"chakra-link css-128fqrf\" aria-label=\"and beyond permalink\" href=\"#and-beyond\"><svg viewbox=\"0 0 24 24\" focusable=\"false\" class=\"chakra-icon css-173jpr1\"><g fill=\"currentColor\"><path d=\"M10.458,18.374,7.721,21.11a2.853,2.853,0,0,1-3.942,0l-.892-.891a2.787,2.787,0,0,1,0-3.941l5.8-5.8a2.789,2.789,0,0,1,3.942,0l.893.892A1,1,0,0,0,14.94,9.952l-.893-.892a4.791,4.791,0,0,0-6.771,0l-5.8,5.8a4.787,4.787,0,0,0,0,6.77l.892.891a4.785,4.785,0,0,0,6.771,0l2.736-2.735a1,1,0,1,0-1.414-1.415Z\"\/><path d=\"M22.526,2.363l-.892-.892a4.8,4.8,0,0,0-6.77,0l-2.905,2.9a1,1,0,0,0,1.414,1.414l2.9-2.9a2.79,2.79,0,0,1,3.941,0l.893.893a2.786,2.786,0,0,1,0,3.942l-5.8,5.8a2.769,2.769,0,0,1-1.971.817h0a2.766,2.766,0,0,1-1.969-.816,1,1,0,1,0-1.415,1.412,4.751,4.751,0,0,0,3.384,1.4h0a4.752,4.752,0,0,0,3.385-1.4l5.8-5.8a4.786,4.786,0,0,0,0-6.771Z\"\/><\/g><\/svg><\/a>And beyond<\/h2>\n<p class=\"chakra-text css-gi02ar\">Interop marked a major inflection point for Eth2. There is still much work to accomplish before launch, but engineering efforts will increasingly be geared toward testnets, optimizations, and usability &#8212; work that begins to shift this software into the hands of users.<\/p>\n<p class=\"chakra-text css-gi02ar\">So what&#8217;s up next for client teams and eth2 development?<\/p>\n<ul role=\"list\" class=\"css-1ars4k6\">\n<li class=\"css-0\">Benchmarks and optimizations<\/li>\n<li class=\"css-0\">Test sync, stress test networks, etc<\/li>\n<li class=\"css-0\">Public and incentivized testnets<\/li>\n<li class=\"css-0\">Third party audits<\/li>\n<li class=\"css-0\">Polishing the validator user experience<\/li>\n<\/ul>\n<p class=\"chakra-text css-gi02ar\">Finally, we owe a special thank you to the <a target=\"_blank\" rel=\"noopener\" class=\"chakra-link css-vezwxf\" href=\"https:\/\/consensys.net\">ConsenSys<\/a> team for helping to organize, host and provide resources that made Interop possible.<\/p>\n<\/div>\n<p><script async src=\"\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><br \/>\n<br \/><br \/>\n<br \/><a href=\"https:\/\/blog.ethereum.org\/en\/2019\/09\/19\/eth2-interop-in-review\">Source link <\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Last week, seven of the eight Eth2 clients under active development succeeded in marking the major milestone of moving from single-client to multi-client testnets at the &#8220;Interop Lock-in&#8221;. With this exciting success in Eth2 development, we wanted to reflect on how this point was reached and on what it means to the Ethereum network and [&hellip;]<\/p>\n","protected":false},"author":6,"featured_media":18357,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"tdm_status":"","tdm_grid_status":"","footnotes":""},"categories":[24],"tags":[],"kronos_expire_date":[],"class_list":["post-18444","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-ethereum"],"_links":{"self":[{"href":"https:\/\/cryptoted.net\/index.php\/wp-json\/wp\/v2\/posts\/18444","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cryptoted.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cryptoted.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cryptoted.net\/index.php\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/cryptoted.net\/index.php\/wp-json\/wp\/v2\/comments?post=18444"}],"version-history":[{"count":0,"href":"https:\/\/cryptoted.net\/index.php\/wp-json\/wp\/v2\/posts\/18444\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cryptoted.net\/index.php\/wp-json\/wp\/v2\/media\/18357"}],"wp:attachment":[{"href":"https:\/\/cryptoted.net\/index.php\/wp-json\/wp\/v2\/media?parent=18444"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cryptoted.net\/index.php\/wp-json\/wp\/v2\/categories?post=18444"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cryptoted.net\/index.php\/wp-json\/wp\/v2\/tags?post=18444"},{"taxonomy":"kronos_expire_date","embeddable":true,"href":"https:\/\/cryptoted.net\/index.php\/wp-json\/wp\/v2\/kronos_expire_date?post=18444"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}