
SE @metalbear Former developer @yoapp. Die hard Hapoel fan.
Israel
Joined June 2009
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Red Alert app featured today in the @nytimes! goo.gl/Pxi349 by @rudoren #IsraelUnderFire #Gaza #Hamas
Ari Sprung retweeted
It's finally happening.
mirrord has always been Kubernetes-only. We can't tell you how many hearts we had to break when telling people they couldn't run their code against their real staging environment without a deploy (a dev loop measured in seconds instead of CI runs, fewer environments to pay for, tests against real dependencies instead of a guess at them), because their stack runs on ECS or Lambda or whatever. Agents have been taking this news even worse.
That's about to change. mirrord Beyond Kubernetes brings the same workflow to Lambda, ECS, Cloud Run, Vercel and more.
The waitlist is open, and the platform with the most signups gets support first.
metalbear.com/mirrord/beyondโฆ
Ari Sprung retweeted
My twitter feed recently was full of everyone posting about building sandboxes for AI agents. The issue with sandboxes is that they start empty, so the agent first builds a replica of what your system looks like and then tests against it. What agents actually need is a playground: your real staging environment, where they can test their its changes isolated from everyone else.
Wrote about how I set this up for my own agent here: metalbear.com/blog/ai-agent-โฆ
Ari Sprung retweeted
Replying to @deedydas
@deedydas suggest solving it with old ways - more compute, more efficiency, more cache. Beyond amount of CI needed, there's almost no value in UT when using AI while tremendous value lies in E2E.
None of the listed companies help you run E2E better/faster.
The biggest cost of E2E is spinning up a real-environment.
our (@metalbear) approach with mirrord offers something different - give each test/ai/engineer a slice of a real environment, isolating flows allowing infinite scale while almost zero cost (beyond compute needed for the tests). Use it in CI, in CD and in the cloud agents it selves to have everyone iterating against same baseline.
for example - metalbear.com/mirrord/case-sโฆ
or @fagamericano who writes a lot about it (also mirrord user :D)
As cost of coding has plummeted, long builds (CI) has become a bottleneck for many software cos. Three of the biggest startups solving this:
1. Blacksmith (@useblacksmith)
2. Namespace (@namespacelabs)
3. Depot (@depotdev)
Ari Sprung retweeted
Take a read ๐
This week @dorco8 and @EBukchin's webinar left such an impression on me that I ended up writing a blog about :P
If you missed the webinar (or prefer text over video) and want to learn how @mondaydotcom runs its agent evals read the blog here: metalbear.com/blog/monday-agโฆ
Ari Sprung retweeted
I cannot express how totally necessary are canaries in Agentic SDLC.
When we work on our @openclaw fork we use two techniques:
-> devcontainers with mirrord to intercept GKE cluster calls as local on the service/image currently working on. So when I write to my Agent on Slack the call is intercepted and routed to the openclaw instance running on my dev machine. Calls out go back into the cluster as if it was running on it.
-> when done I can annotate a set of users as canary targets and have their openclaw instances flip to the new image. Having added telemetry and enabled debug modes I (and my agents) can verify everything is working as expected then flip the whole cluster to run the new image.
If any agent on that chain makes a mistake itโs OK it doesnโt affect the whole fleet just a pod or two that it knows to rollback.
You need to work on setting up your Agentic SDLC to mitigate risks. The infrastructure primitives are there.
Ari Sprung retweeted
ืืชืคืืืช ืจืืฉ ืืืืฉ ืืฉืคืืชืืช ืืืืงืจ: ืืืื ืืืืื ืฉื ืืืื ืืจืืคืจ ืืืจื ืืืชื ืืงืจืืช ืืืืืจืืช.
ืืืงืฉืช ืืืืื, ืืื ื ืืกื "ืื ืฉืืจื" ืืืืื ืฉืืื ืืื ืืฉืืจ ืืช ืืืืืื ืดืจืื ืฉื ืืืืื, ืจืื ืฉื ืืืืช ืืขื, ืืืืื ื ืืืืจืฅ, ืจืื ืฉื ืฉืืืืืช, ืจืื ืฉื ืืืื ืืื ืืืงื ืขื ืืฉืจืืืด.
Ari Sprung retweeted
"After @claudeai finishes its task, a mirrord Preview Environment is spun up and then anybody on the team can come and review it."
โ Itay Hilel, AI Automation Engineer at Daylight Security
Watch Itay Hilel and Shira Lev from @DaylightSec share how their team tests every change made by Claude Code and @OpenAI's Codex. With mirrord Preview Environments, it all happens in a production-like environment, safely and with zero extra infra ๐
Read the full case study here: metalbear.com/mirrord/case-sโฆ
Ari Sprung retweeted
ืขื ืจ ื"ื ืืื ืืืืืื ืชืื ืืช ืืืจืื ืืื ืืืืจ ืืจืื ืืืื ืืืจืื ืืืืื ืขื ืืื ืฉืื. ืืืฆืืื ืฉืืจื, ืืืืืื ืื ืจืื ืืืชื ืืื ืกืช ืืืื, ืืืืข ืืขื ืืืงืจ ืืื ืขืื ืืืืจ ืืืฆืืชื ืฉื ืขื ืจ ืืืืืืจ ืฉืื ืืื ืจืืืง ืืื ืฉืืฉ ืฉื ืขืืฉืื
Ari Sprung retweeted
Next week weโre doing something big. 5 days, 5 new product feature launches! ๐
If youโd like to follow along, bookmark the Launch Week landing page here: metalbear.com/launch-week/
Or join our Slack community to receive daily updates during Launch Week: metalbear.com/slack
We have some interesting surprises and a game for you to compete in (with prizes, of course), so stay tuned! ๐ป
Ari Sprung retweeted
BREAKING NEWS: Jared Harper, the Back-to-Back MVP of both the EuroCup and the Israeli Winner League, has signed a 3 year contract extension with us until the end of the 2028/29 season, according to myself
Yalla Jared and Yalla Hapoelโค๏ธ @Therealvinoo
Ari Sprung retweeted
Testing local code against a remote Kubernetes cluster usually means dealing with slow CI pipelines or complex staging setups.
In this on-demand webinar, MetalBear walks through how they use the open-source tool mirrord to connect local processes directly to a remote clusterโsaving time without deploying.
Watch the session here: community2.cncf.io/e/mm6ugd/
Ari Sprung retweeted
ืคื ืื ืืฉืจ ืืืืฆืจ ืฉืืคืฆืืฅ ืืฆืืืฆืื ืืืืืงืจ: ืจืฉืช ื-X ืืื ืืงืื ื ืคืื ืขืืืจ ืขืืชืื ืืื ืคืืืืืฆืืกืืื ืืกืชื ืืืจืืื ืืืฉืืจื.
ืืืงืื ืืืจืืื ืฉืื - ืื ืืงืืื ื.
ืืื ืื ืฉืืชื ืื ืืชืืื ื ืืืืจืืืช, ืืืื ืืืื ืฉืชืชืจืื ืืืฉืืจื ืืขืฉืืช ืขื ืื ืืฉืื ืืชืืจ ืืืจ ืืืืจ ืืงืืื ื?
True. @metalbear
Ari Sprung retweeted
Companies like monday.com, zooplus, and SurveyMonkey use #mirrord to ship faster by connecting local code to live @kubernetesio environments.
Curious how it works? Check out this video ๐
Learn more about mirrord here: metalbear.com/mirrord/?utm_sโฆ
Ari Sprung retweeted
Replying to @threepointone
Thatโs what weโre building, minus the need to actually deploy - mirrord.dev
Had a blast !
We just had our first company retreat last week in Biella, Italy โ planning sessions, great food and wine, and river rafting in a thunderstorm (the thunderstorm part wasn't intentional)
We're a fully remote team spread across 15 countries, so moments like these are really special for us!
If you'd like to join the next one, we're hiring :)
metalbear.com/careers/?utm_sโฆ
Pleasure listening to @Therealvinoo sharing his emotions after quarters loss. Lucky to have him on our team. โฅ๏ธ๐ค
Ari Sprung retweeted
ืื ื ืืืื ืืื ืืืฉืชื. ืืกืคืจ ืืืฆื ืืขืืจืืช ืืืฉืจืื ื-11 ืืืื.
nytimes.com/2026/04/19/booksโฆ
whenweseeyouagainbook.com/
Ari Sprung retweeted
ืืืืืื ืืืฆืืื ืฉืืืงืกื ืืื ืืืืข ืืื ืงืจืื ืฉืืคืฉืจ ืื ืืื ืฉืืืืฅ ืืืืงืืื ืืืืืืืช
ืืฉืื ืืฉืืชืืคืื
Last Friday, just before the start of
Shabbat, I went to what I consider the holiest spot in the childrenโs hospital, the small corner where Jewish mothers come to light Shabbat candles. These are mothers whose children are fighting cancer and other serious illnesses. I watched them stand there, praying over the candlelight for mercy and healing for their child. With every whispered prayer I heard, I also saw their tears fall, but in my heart, I felt those tears rising straight up to heaven.
Over time, it has become my own weekly ritual: every Friday, when I come to bring Lego sets to the kids in the hospital, I stop and watch these mothers pray with such strength and pain.
This past Friday, I brought a Winnie the Pooh Lego set with me.
I stood near the candles, and this time I found myself crying too.
Gazing at the flames, I began to pray:
โPlease, God, I beg You, bring him back safely.โ
Unlike other missing soldiers of Israel where I know their names and families, I donโt even know this American navigatorโs name. But I decided to pray for him anyway. As he flies through the sky on his mission, I feel that he is in Godโs hands.
I thought about President Trump;
How much must weigh on his mind,
How much effort is likely being invested into finding this missing U.S. navigator,
What he might be doing right now to bring him home.
I see this navigator as a son of God
Brave enough to go out on a mission to protect us, Am Yisrael,
Carrying with him the values of the United States of America.
Holding the Winnie the Pooh Lego box, I made a promise:
If this American navigator returns safely, I will donate $180 to tzedakah, and I will buy another Lego set for a child battling cancer.
I have already donated once in his merit, and I will donate again to give thanks when he comes home.
You might ask: why Winnie the Pooh?
In the film *Goodbye Christopher Robin*, there is a scene where a soldier is missing in war.
His parents receive a message that he is missing and assume he has been killed.
After a long time, the soldier suddenly returns home alive.
That story stayed with me.
President Trump has already done a great deal to help bring our hostages home and has supported the Israeli government and our Prime Minister, Benjamin Netanyahu.
I believe he needs and deserves our prayers now, for the safe return of this missing American navigator.
So today, when I go back to the childrenโs hospital
To that place where women light Shabbat candles with tears in their eyes
I will choose a boy or girl to receive the Winnie the Pooh Lego set,
And I will give it with a prayer and intention that God will help bring the missing American navigator home.
God bless America.



























