Ari Lerner writes code and mathematics, builds hardware and systems, and teaches across secure AI infrastructure, systems software, and new computing models.https://ari.io/en-ushttps://ari.io/writing/how-to-build-around-an-open-theorem-without-claiming-it/https://ari.io/writing/how-to-build-around-an-open-theorem-without-claiming-it/A growing body of checked mathematics can still leave its central theorem unresolved, so the repository has to show exactly where the gap remains.Sat, 15 Aug 2026 02:08:00 GMTdeep-techuorleanmathematicsresearchhttps://ari.io/writing/a-registry-is-a-graph-not-a-bucket/https://ari.io/writing/a-registry-is-a-graph-not-a-bucket/PUT and GET were enough for blobs, until a release needed names, dependencies, signatures, and one visible moment of publication.Sat, 15 Aug 2026 02:07:00 GMTdeep-techuorregistriesstoragedistributed-systemshttps://ari.io/writing/a-program-should-be-able-to-resume-somewhere-else/https://ari.io/writing/a-program-should-be-able-to-resume-somewhere-else/Copying memory can restore a process on the same host; moving a program somewhere else requires its dependencies, runtime contract, and fresh authority.Sat, 15 Aug 2026 02:06:00 GMTdeep-techhologramruntimesportabilitycontent-addressinghttps://ari.io/writing/research-should-record-what-failed/https://ari.io/writing/research-should-record-what-failed/An experiment is not a decision until its result can tell us to adopt the idea, repair the instrument, or close the direction.Sat, 15 Aug 2026 02:05:00 GMTdeep-techuorairesearchmeasurementhttps://ari.io/writing/the-browser-is-a-computer-not-a-thin-client/https://ari.io/writing/the-browser-is-a-computer-not-a-thin-client/A browser demo failed before the model finished downloading, forcing the pipeline to treat the browser as the user’s computer rather than a remote shell.Sat, 15 Aug 2026 02:04:00 GMTdeep-techhologrambrowserwasmaihttps://ari.io/writing/exactness-is-an-interface/https://ari.io/writing/exactness-is-an-interface/A valid matrix multiplication should not change its meaning just because I offered less scratch memory to the fast kernel.Sat, 15 Aug 2026 02:03:00 GMTdeep-techuorrustmathematicsperformancehttps://ari.io/writing/a-hash-can-prove-an-answer-was-not-changed/https://ari.io/writing/a-hash-can-prove-an-answer-was-not-changed/A content hash can preserve an AI answer perfectly while telling me nothing about whether the computation behind it was correct.Sat, 15 Aug 2026 02:02:00 GMTdeep-techhologramaiverificationcontent-addressinghttps://ari.io/writing/meaning-needs-an-address/https://ari.io/writing/meaning-needs-an-address/I kept arguing with bytes before the hash because canonicalization—not SHA-256—decides which representations count as the same object.Sat, 15 Aug 2026 02:01:00 GMTdeep-techuorcontent-addressingidentityrusthttps://ari.io/writing/delete-everything-except-the-ability-to-prove-who-you-are/https://ari.io/writing/delete-everything-except-the-ability-to-prove-who-you-are/MVM’s cleanup command promised an empty machine but deleted only the directories somebody remembered to list.Fri, 14 Aug 2026 23:51:00 GMTdeep-techmvmoperationssecurityidentityhttps://ari.io/writing/a-1-gib-filesystem-cost-3-9-gib-of-ram/https://ari.io/writing/a-1-gib-filesystem-cost-3-9-gib-of-ram/A Rust ext4 builder kept the source tree, a cloned plan, and the final image alive at once; ownership made the memory spike predictable.Fri, 14 Aug 2026 23:52:00 GMTdeep-techmvmrustperformancefilesystemshttps://ari.io/writing/provenance-is-not-logging/https://ari.io/writing/provenance-is-not-logging/A signed MVM event could prove what happened without explaining who authorized the launch or what decision led to it.Fri, 14 Aug 2026 23:53:00 GMTdeep-techmvmprovenanceauditsecurityhttps://ari.io/writing/200-milliseconds-is-not-a-boot-time/https://ari.io/writing/200-milliseconds-is-not-a-boot-time/I measured a microVM entering the kernel quickly, then realized the stopwatch had ignored most of what the user was waiting for.Fri, 14 Aug 2026 23:54:00 GMTdeep-techmvmperformancemicrovmssystemshttps://ari.io/writing/snapshots-can-clone-memory-not-authority/https://ari.io/writing/snapshots-can-clone-memory-not-authority/A forked microVM can inherit warm computation without inheriting the parent’s identity, channels, secrets, or authority.Fri, 14 Aug 2026 23:55:00 GMTdeep-techmvmmicrovmssnapshotssecurityhttps://ari.io/writing/a-security-claim-is-code/https://ari.io/writing/a-security-claim-is-code/An OCI security test passed because the image was harmless, not because the runtime enforced the privilege boundary the documentation promised.Fri, 14 Aug 2026 23:56:00 GMTdeep-techmvmsecuritytestingrusthttps://ari.io/writing/the-safest-nic-is-no-nic/https://ari.io/writing/the-safest-nic-is-no-nic/I kept adding policy around a guest network device until I realized the device itself was the network authority I was trying to control.Fri, 14 Aug 2026 23:57:00 GMTdeep-techmvmsecuritynetworkingmicrovmshttps://ari.io/writing/ai-agents-need-a-machine-boundary/https://ari.io/writing/ai-agents-need-a-machine-boundary/Prompt rules are not a security boundary. Agent runtimes need enforceable capabilities, isolated execution, mediated I/O, and a deliberately small blast radius.Fri, 14 Aug 2026 00:00:00 GMTaisecuritysystemsrusthttps://ari.io/writing/invisible-ai/https://ari.io/writing/invisible-ai/The advances in AI are incredible, but the most important systems will disappear into ordinary life.Mon, 25 Mar 2024 00:00:00 GMTaiproductfuturehttps://ari.io/writing/leetcode/longest-valid-parentheses/https://ari.io/writing/leetcode/longest-valid-parentheses/A stack-based Rust walkthrough for LeetCode's Longest Valid Parentheses problem.Sun, 05 Nov 2023 00:00:00 GMTleetcoderustcoding-challengestackshttps://ari.io/writing/cybersecurity/root-me/room-1-ssrf/https://ari.io/writing/cybersecurity/root-me/room-1-ssrf/A Root-Me lab walkthrough exploring SSRF, local services, Redis, and a reverse-shell payload in an authorized environment.Tue, 03 Oct 2023 00:00:00 GMTsecurityhackingtechnicaltutorialroot-messrfhttps://ari.io/writing/leetcode/leads-common-ancestor-of-a-binary-tree/https://ari.io/writing/leetcode/leads-common-ancestor-of-a-binary-tree/A recursive JavaScript solution for finding the lowest common ancestor of two nodes in a binary tree.Wed, 20 Sep 2023 00:00:00 GMTleetcodejavascriptcoding-challengetreeshttps://ari.io/writing/leetcode/three-sum-closest/https://ari.io/writing/leetcode/three-sum-closest/A Rust two-pointer solution for finding the three-number sum closest to a target.Tue, 19 Sep 2023 00:00:00 GMTleetcoderustcoding-challengetwo-pointershttps://ari.io/writing/leetcode/three-sum/https://ari.io/writing/leetcode/three-sum/A Rust walkthrough of the sorted two-pointer solution for finding unique triplets that sum to zero.Fri, 15 Sep 2023 00:00:00 GMTleetcoderustcoding-challengetwo-pointershttps://ari.io/writing/leetcode/swap-nodes-inpairs/https://ari.io/writing/leetcode/swap-nodes-inpairs/A recursive Rust solution for swapping adjacent nodes in a singly linked list without changing their values.Thu, 14 Sep 2023 00:00:00 GMTleetcoderustcoding-challengelinked-listhttps://ari.io/writing/ways-ai-will-change-our-lives/https://ari.io/writing/ways-ai-will-change-our-lives/An archived January 2023 view of where AI seemed likely to reshape transportation, medicine, energy, business operations, and customer service.Mon, 09 Jan 2023 00:00:00 GMTfuturebusinesspredictionsAIhttps://ari.io/writing/cybersecurity/binary-exploitation/https://ari.io/writing/cybersecurity/binary-exploitation/A beginner-friendly ret2libc and ROP walkthrough using Ghidra, GDB/GEF, pwntools, and a picoCTF binary.Wed, 08 Jun 2022 00:00:00 GMTsecurityhackingtechnicaltutorialbinary-exploitationpicoctfhttps://ari.io/writing/picoctf/transformation/https://ari.io/writing/picoctf/transformation/Reverse a picoCTF encoding challenge by unpacking two ASCII characters from each Unicode code point.Wed, 25 May 2022 00:00:00 GMTctfsecuritycybersecuritypicoctfreverse-engineeringpythonhttps://ari.io/writing/picoctf/nice-netcat/https://ari.io/writing/picoctf/nice-netcat/A beginner picoCTF walkthrough: connect with netcat, decode decimal ASCII, and automate the result with a small Python socket program.Mon, 25 Apr 2022 00:00:00 GMTctfsecuritycybersecuritypicoctfpythonhttps://ari.io/writing/little-empire/https://ari.io/writing/little-empire/Your little empire is built one investment, one income stream, and one small bet at a time.Tue, 22 Mar 2022 00:00:00 GMTbusinessauthoritylifehttps://ari.io/writing/disappear-like-jason-bourne/https://ari.io/writing/disappear-like-jason-bourne/A 2022 snapshot of the steps I was taking to reduce data leakage, identity exposure, and casual tracking online.Sat, 12 Mar 2022 00:00:00 GMTsafetysecuritycybersecurityprivacyhttps://ari.io/writing/blue-sky-cream-soda/https://ari.io/writing/blue-sky-cream-soda/Memories of my father, a hot-air-balloon festival, and the cream soda that still carries him with it.Sat, 12 Feb 2022 11:39:00 GMTlifebusinessauthenticity