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dims / ci-fixes-since-v137-code-freeze-2026-08-03.md
Created August 3, 2026 13:58
Kubernetes CI: fixed since v1.37 code freeze (2026-07-22 → 2026-08-03) — wins, verification, call to action

Kubernetes CI: Fixed Since v1.37 Code Freeze — Wins, Verification, and Call to Action

Window: 2026-07-22 (Code Freeze AoE; enforced 2026-07-23 12:00 UTC via test-infra#37475) → 2026-08-03 Release: v1.37 Compiled: 2026-08-03 (~13:30 UTC data). All "status now" claims verified against live prow job history, TestGrid summary JSON, k8s-triage failure_data.json (2026-08-03 11:43 UTC), and k8s-metrics (2026-08-03 12:05 UTC).


TL;DR (for the email)

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dims / README.md
Last active July 30, 2026 22:05
copyconstruct-debugging: Claude Code skill for debugging tricky bugs (diagnosis before remedy, fail-first verification)

copyconstruct-debugging

A Claude Code skill that enforces debugging discipline on hard bugs — memory leaks, races, routing/sharding issues, regressions. Diagnosis before remedy, evidence ranking, contradiction chasing, fail-first verification.

Inspired by Cindy Sridharan (@copyconstruct)'s post observing that Claude's initial analysis on tricky bugs is almost always wrong until you feed it hypotheses, clues, and suggestions. These are the generalized principles Claude itself distilled when asked: "so, what did you learn?"

Install as a Claude Code skill

mkdir -p ~/.claude/skills/copyconstruct-debugging
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dims / 2026-07-24-enroot-libnvidia-container-cdi.md
Created July 24, 2026 22:28
Enroot, libnvidia-container, and a path to CDI — architecture notes and migration design

Enroot, libnvidia-container, and a path to CDI

Date: 2026-07-24

Sources examined at these versions:

  • enroot at commit ead3a25 (v4.2.0), /Users/dsrinivas/go/src/github.com/nvidia/enroot
  • libnvidia-container at commit 3e428194 (v1.19.1 plus 26 commits), /Users/dsrinivas/go/src/github.com/nvidia/libnvidia-container
  • nvidia-container-toolkit at commit da5f20fb (after v1.19.0), /Users/dsrinivas/go/src/github.com/nvidia/nvidia-container-toolkit
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dims / dataplane-pluggability.md
Last active June 28, 2026 13:37
Agent Substrate — Dataplane Pluggability (design doc, proposed)

Dataplane Pluggability

Status: Proposed, for review. This is an RFC, a position proposal. It is not an approvable architecture decision record, and it is not a contract. Several questions below, including who owns capacity, the lifecycle shape, and how providers are discovered, can still change what the chosen boundary means in practice. The contract sketches in it are illustrative, and a number of questions are still open (see Open questions). The target design is not built yet. What exists on main today is described in The dataplane today and [Current

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dims / 2026-06-25-microvm-pr287-runbook.md
Last active June 25, 2026 16:05
Agent Substrate micro-VM (PR #287) runbook on a kind cluster: counter-microvm + OpenShell helpdesk-microvm demos, validated end-to-end (suspend/resume of cloud-hypervisor VM snapshots).

Micro-VM (substrate PR #287) on bigbox — runbook

Stand up the agent-substrate micro-VM runtime (cloud-hypervisor + kata-agent, PR #287) on a kind cluster on bigbox and run two demos, then tear it down:

  • Part A — counter-microvm: in-RAM counter → suspend (VM memory snapshot) → resume on another worker → count continues. The runtime's own demo; pure substrate.
  • Part B — helpdesk-microvm: the OpenShell helpdesk agent running as a micro-VM actor → /status + /chat (real gpt-oss:20b-cloud completions via Ollama Cloud) → suspend → resume → state continues. Proves a real ~3 GB agent workload boots, does name-based egress, snapshots, and
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dims / criu-checkpoint-restore-design.md
Created June 10, 2026 17:32
Kata Containers CRIU checkpoint/restore — design + intern test guide (PoC: dims/kata-containers criu-cr-containerd)

CRIU Checkpoint / Restore for Kata Containers

Status: prototype against Kata 3.31.0 (runtime-rs). Validated end-to-end (via shim-ctl): a counter's in-memory state survives 3 checkpoint/restore cycles (monotonic, no reset), a live TCP LISTEN socket survives, a ~10 MB memory buffer survives, and a checkpoint restores in a fresh microVM (migration-style). Engine-driven: both ctr (containerd native) and crictl (CRI, no kubelet) do the full checkpoint→restore cycle with the counter surviving; crictl restore needs containerd ≥ 2.3.0. See Proof of concept for the branches.

Motivation

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dims / 2026-06-03-substrate-cross-vendor-contributors.md
Created June 4, 2026 13:35
Agent Substrate (agent-substrate/substrate) — Cross-Vendor Contributor & Affiliation Report (2026-06-03)

Agent Substrate — Cross-Vendor Contributor & Affiliation Report

Generated: 2026-06-03 Repo: agent-substrate/substrate"Agent Substrate: the core system" (public, 468★, Apache-2.0) What it is: a system on top of Kubernetes that manages agent-like workloads at higher scale/lower latency by taking the K8s control-plane out of the critical path — actors run in gVisor sandboxes (ateom), managed by a kubelet-like agent (atelet), with GCS checkpoint/restore (ategcs) and a router (atenet). Window: 2026-05-13 → 2026-06-03 (~3 weeks — a brand-new seed project) Volume analyzed: 95 commits · 117 PRs (all states) · 63 issues (all states) Analysis basis: upstream agent-substrate/substrate@main (e26cfa22), cloned fresh — the local dims/substrate fork checkout (4cbac18) was a few commits behind.

Framing: Unlike the NVIDIA-owned reports (nvsentinel / dra-driver / aicr / OpenShell), this repo is not NVIDIA-owned — it's a

@dims
dims / external-contributor-report.md
Created June 3, 2026 14:40
OpenShell (NVIDIA/OpenShell) — External Contributor & DCO-Hygiene Report (2026-05-26)

External Contributor & DCO-Hygiene Report — nvidia/OpenShell

  • Generated: 2026-05-26
  • Repository: nvidia/OpenShell (working copy: /Users/dsrinivas/go/src/github.com/nvidia/OpenShell)
  • Total commits analyzed (full main history): 754
  • Total unique commit-author emails: 58
  • Total unique GitHub handles (resolved): 51 (excluding bots)

Methodology summary

@dims
dims / 2026-06-03-aicr-external-contributors.md
Created June 3, 2026 14:30
aicr (NVIDIA/aicr) — External Contributor & DCO-Hygiene Report (2026-06-03)

aicr — External Contributor & DCO-Hygiene Report

Generated: 2026-06-03 Repo: NVIDIA/aicr"Tooling for optimized, validated, and reproducible GPU-accelerated AI runtime in Kubernetes" (323★) History analyzed: 2026-01-30 → 2026-06-03 (~4 months), main @ f65d7b0 Total commits analyzed: 1,205 (44 unique author emails → 35 distinct GitHub handles + 3 bots) Analysis basis: working copy is the dims/aicr2 fork; its main HEAD (f65d7b0eddcda…) is identical to upstream NVIDIA/aicr@main, so the local history faithfully represents upstream.

Methodology: Extracted every commit author via git log (email, name, date, and Signed-off-by trailer via %(trailers)) → resolved each email to a GitHub login through the upstream commit API (GET /repos/NVIDIA/aicr/commits/{sha}.author.login) → classified each handle by (1) Helios LDAP match, (2) @nvidia.com commit email, (3) NVIDIA GitHub-org membership (`GET /orgs/NVIDIA/member

@dims
dims / 1-2026-05-29-firecracker-ateom-poc-bigbox.md
Created May 29, 2026 19:18
Agent Substrate — pluggable ateom backend: Firecracker (microVM). [1] PoC on bigbox, [2] design proposal, [3] implementation log.

Firecracker ateom Backend — Working PoC on bigbox (counter demo)

Update (2026-05-29): this standalone PoC has since been turned into a full in-repo implementation (Phases 0–3) and a cluster e2e — a counter actor on a Firecracker worker driven through the real control plane (ate-api-server + atenet), state preserved across suspend/resume, on the existing kind cluster. Branch firecracker-backend (pushed to dims/substrate, commit bc533f5; worktree ~/go/src/github.com/agent-substrate/substrate-firecracker). Full journal: ~/notes/agent-substrate/2026-05-29-firecracker-backend-implementation-log.md. The PoC notes below are retained for the from-scratch microVM bring-up details (rootfs build, Firecracker API sequence, gotchas).

  • Date: 2026-05-29 · Host: bigbox (Ubuntu 24.04, AMD EPYC 7763, nested KVM) · Firecracker: v1.15.1 · Guest kernel: vmlinux-6.1.128
  • Goal: prove a Firecracker backend can satisfy substrate's ateom Run/Checkpoint/Restore contract, preserving