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LEARNING PATHS

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How to fix pull access denied for minio/minio in Docker

The pull access denied for minio/minio error appears because MinIO removed its Docker Hub images in September 2026, and quay.io has required an account since the 24th. Point your compose file at cgr.dev/chainguard/minio, at the pgsty/silo fork or at an image built from source: your existing data keeps working.

Tools
14 min 245

How to migrate from MinIO to Garage with Docker

MinIO images no longer pull from Docker Hub, and the quay.io copy is frozen in 2025. To migrate from MinIO to Garage with Docker, run Garage v2.4.1 next to MinIO, copy the buckets with rclone sync, verify them with rclone check, and switch endpoint, keys and region in your clients.

How to Install
18 min 208

How to install Portainer with Docker Compose v2

You install Portainer with Docker Compose by writing a single compose.yaml file and running two commands. Portainer CE 2.40 STS supports Docker Compose v2 natively, enables HTTPS on port 9443 out of the box, and manages Docker Engine, Swarm, Kubernetes and ACI from one panel. It runs on Ubuntu 24.04 or Debian 13.

How to Install
9 min 3.7K 4.7

How to use DeepSeek Harness with a local model

DeepSeek Harness (dsh) is the open-source agent harness DeepSeek released in August 2026. It works with a local model if you declare an openai-completions provider in settings.yaml that points at llama-server, with a placeholder key and the real context size. With Qwen3.5-4B on CPU it left the tests green in 4 of 5 attempts, but slowly.

AI Agents
19 min 142

NIST PQC: The Post-Quantum Cryptography Standards

In August 2024, NIST published its first finalized post-quantum cryptography standards: FIPS 203 (ML-KEM) for key exchange, FIPS 204 (ML-DSA) for digital signatures, and FIPS 205 (SLH-DSA) as a hash-based alternative. They replace RSA and ECDSA before a quantum computer can break them, and hybrid implementations are already live in Chrome and Cloudflare.

Technology
9 min 3.5K 4.4

How to enable Paperless-ngx 3 local AI with Ollama

Paperless-ngx 3 suggests title, tags, correspondent and dates with an LLM and answers questions about your documents, all locally with Ollama. You upgrade from 2.20.15 by changing the image tag. On CPU, Gemma 4 E4B took 25.8 s per suggestion and used about 7 GiB, provided you dodge a bug with reasoning models.

How to Install
20 min 97

LATEST POSTS Just out

Fresh from the oven

  1. Artificial Intelligence

    How to red-team a local LLM with garak 0.17 and Ollama

    garak 0.17 is NVIDIA's LLM vulnerability scanner: it fires prompt injection, jailbreak, encoding and data-leak probes at your model and counts the failures. Against gemma3 1B on Ollama, on CPU, prompt injection succeeded 66.67% to 93.33% of the time, and a defensive system prompt did not stop it.

    13 min 4
  2. Tools

    How to upgrade Gitea 1.27 to Gitea 28 with Docker without breaking webhooks or mirrors

    To upgrade Gitea 1.27 to Gitea 28 with Docker, stop the container, dump PostgreSQL and the /data volume, remove the legacy egress keys from app.ini and change the tag. In my test a wildcard BLOCKED_DOMAINS entry that was valid on 1.27 stopped 28 from starting, and webhooks to public hosts started going out again.

    17 min 18
  3. AI Agents

    How to migrate your MCP server to FastMCP 4 and the Python SDK 2

    If your server imports mcp.server.fastmcp, upgrading the mcp package to version 2 breaks it: FastMCP was renamed MCPServer. You have two destinations, MCPServer or FastMCP 4, and both require moving host and port to run(), building MCPError from a code and a message, and replacing ctx.elicit, which fails on 2026-07-28 connections.

    22 min 9
  4. Tools

    How to install Gatus with Docker Compose, monitoring as code vs Uptime Kuma

    Gatus is an uptime monitor you configure with YAML files instead of a web interface. With Docker Compose, the v5.37.0 image and a volume for SQLite, it checks HTTP, TCP, certificates and DNS TXT records, and alerts through a webhook. In my test it alerted on an nginx outage after 30 seconds, the time three 10-second checks take.

    14 min 9
  5. Tools

    How to fix pull access denied for minio/minio in Docker

    The pull access denied for minio/minio error appears because MinIO removed its Docker Hub images in September 2026, and quay.io has required an account since the 24th. Point your compose file at cgr.dev/chainguard/minio, at the pgsty/silo fork or at an image built from source: your existing data keeps working.

    14 min 245
  6. Tools

    How to install Open WebUI with Docker and Ollama, slim image included

    Open WebUI 0.11.4 installs from a two-service docker-compose.yml: Ollama runs the models and the slim Open WebUI image, which on arm64 downloads 176 MB against 1.49 GB for the full one, serves the interface. This guide creates the admin account, chats with a local model and turns on tool approval.

    16 min 12
  7. Technology

    CVE-2026-80521 container escape: check your Docker and k3s hosts and mitigate it

    CVE-2026-80521 is a use-after-free in the Linux kernel's AF_UNIX socket garbage collector, with a public container escape exploit since 22 September 2026. You are affected if your kernel is 6.10 or later without the fix, or a 6.1 or 6.6 branch that received the backport. Patch and reboot; until then, isolate untrusted workloads with gVisor.

    18 min 26
  8. Tools

    How to migrate from MinIO to RustFS 1.0 with Docker

    To migrate from MinIO to RustFS 1.0 with Docker, run RustFS next to MinIO, import the users with mc admin cluster iam, copy the buckets with rclone sync --metadata and compare them with rclone check --download. In my test 4,012 objects arrived identical; versions, tags and public access had to be redone by hand.

    17 min 16
  9. Artificial Intelligence

    How to fix “typical_p is no longer supported” in Ollama

    Ollama 0.34.1 through 0.34.4 reject with HTTP 400 any request to /api/chat or /api/generate that carries typical_p in options, even at 1.0. The fix is to drop the field in the client, go back to 0.34.0, use the /v1 endpoint, or move to 0.40.0, which only logs a warning.

    12 min 13
  10. AI Agents

    How to use Shieldstral as a local guardrail for your agent

    Shieldstral is the 3B safety classifier Mistral released in August 2026: it answers yes or no to a policy written in plain language. Converted to GGUF Q8_0 with llama.cpp and served on a CPU, it blocked no legitimate one among the 100 Spanish and English prompts I prepared, but let 8 of 17 injections through.

    30 min 4

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