qr-cli -- A docker based QR Code generator

Two ways to generate QR codes - pick whichever fits your flow:

1. CLI tool -- generate QR codes by piping flags or JSON straight into the included dockerised qr-cli app, get a JSON
payload back with a base64 image and dataUri. No dependencies (node etc) are required on the host.

2. AI agent skill (/qr) -- generate QR codes, using plain English, which describes all the properties, look and
feel that you want in the QR Code image.

# skill example
/qr https://browserleaks.com/geo rounded, 'dead blue eyes' on 'creamed butter', low error correction WebP 450px with a border and margin of 30px 

The skill translates your description into the right flags and hands the image back inline.

Built on qr-code-styling with a headless NodeJS runtime, node-canvas, Cairo, and Sharp.

Customise dot shapes, corner styles, colours, gradients, embedded logos, error correction levels, and output format (PNG, JPEG, WebP, SVG, dataUri).

Input accepts --key=value flags, a --json='{...}' blob, or piped JSON via stdin - and all three can be combined and merged at invocation time.

Output is always a consistent JSON object:

{ "success": true, "meta": { ...format, dimensions, colours, timing... }, "image": { ...base64, dataUri, filename... } }

Errors use the same schema ("success": false) so jq pipelines never need to branch on output shape or config selection.

Runs as a non-root user in a multi-stage Debian image. Works as a Docker sidecar, local dev tool, or CI step.

Quick start

Option A -- Docker Hub (no clone needed):

# turn off annoying spam export DOCKER_CLI_HINTS=false docker pull rondomondo/qr-cli:latest docker run --rm rondomondo/qr-cli:latest \ --data="https://example.com" \ --format=webp \ --border=10 \ --margin=20 \ --dotsOptions.type=extra-rounded \ --dotsOptions.color="#185FA5" \ --backgroundOptions.color="#E6F1FB" 2> /dev/null \ | jq -r '.image.base64' | base64 -d > qr.webp file qr.webp

Option B -- clone, build, and run the full example suite:

git clone https://github.com/rondomondo/qr-cli.git && cd qr-cli
make build
make examples
make skill-examples

Makefile targets

Usage

Basic -- URL to PNG

docker run --rm rondomondo/qr-cli:latest --project="daveco" \
  --data="https://example.com"

{
  "success": true,
  "meta": {
    "format": "png",
    "mimeType": "image/png",
    "width": 300,
    "height": 300,
    "type": "canvas",
    "data": "https://example.com",
    "project": "daveco",
    "sizeBytes": 1539,
    "durationMs": 147,
    "generatedAt": "2026-05-02T20:17:50.448Z",
    "errorCorrectionLevel": "Q",
    "dotsType": "square",
    "dotsColor": "#000000",
    "backgroundColor": "#ffffff",
    "hasImage": false,
    "margin": 0,
    "border": 0
  },
  "image": {
    "filename": "assets/images/daveco/300x300_000000_FFFFFF_daveco.png",
    "generated": "2026-05-02T20:17:50.448Z",
    "base64": "iVBORw0KGgoAAAANSUhEUgAAASwAAAEsCAYAAAB5fY51AAAABmJLR0...",
    "dataUri": "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAASwAAAEs..."
  }
}

Specify image format

docker run --rm rondomondo/qr-cli:latest \
  --data="https://example.com" \
  --format=svg

{
  "success": true,
  "meta": {
    "format": "svg",
    "mimeType": "image/svg+xml",
    "width": 300,
    "height": 300,
    "type": "svg",
    "data": "https://example.com",
    "sizeBytes": 23837,
    "durationMs": 143,
    "generatedAt": "2026-05-02T20:20:22.495Z",
    "errorCorrectionLevel": "Q",
    "dotsType": "square",
    "dotsColor": "#000000",
    "backgroundColor": "#ffffff",
    "hasImage": false,
    "margin": 0,
    "border": 0
  },
  "image": {
    "filename": "qr.svg",
    "generated": "2026-05-02T20:20:22.495Z",
    "base64": "PD94bWwgdmVyc2lvbj0iMS4wIiBzdGFuZGFsb25lPSJubyI/Pg0KPH...",
    "dataUri": "data:image/svg+xml;base64,PD94bWwgdmVyc2lvbj0iMS4wIiBz..."
  }
}

Full styling via flags

docker run --rm rondomondo/qr-cli:latest \
  --data="https://example.com" \
  --width=400 \
  --height=400 \
  --format=png \
  --border=20 \
  --margin=10 \
  --dotsOptions.type=rounded \
  --dotsOptions.color="#185FA5" \
  --backgroundOptions.color="#E6F1FB" \
  --cornersSquareOptions.type=extra-rounded \
  --cornersSquareOptions.color="#185FA5" \
  --qrOptions.errorCorrectionLevel=H

{
  "success": true,
  "meta": {
    "format": "svg",
    "mimeType": "image/svg+xml",
    "width": 400,
    "height": 400,
    "type": "svg",
    "data": "https://example.com",
    "sizeBytes": 33606,
    "durationMs": 156,
    "generatedAt": "2026-05-02T20:21:20.076Z",
    "errorCorrectionLevel": "H",
    "dotsType": "rounded",
    "dotsColor": "#185FA5",
    "backgroundColor": "#E6F1FB",
    "hasImage": false,
    "margin": 10,
    "border": 20
  },
  "image": {
    "filename": "qr.svg",
    "generated": "2026-05-02T20:21:20.076Z",
    "base64": "PD94bWwgdmVyc2lvbj0iMS4wIiBzdGFuZGFsb25lPSJubyI/Pg0KPH...",
    "dataUri": "data:image/svg+xml;base64,PD94bWwgdmVyc2lvbj0iMS4wIiBz..."
  }
}

Pass a full JSON config

docker run --rm rondomondo/qr-cli:latest \
  --json='{
    "data": "https://example.com",
    "width": 600,
    "height": 600,
    "margin": 20,
    "format": "png",
    "project": "daveco",
    "border": 10,
    "dotsOptions": {
      "type": "extra-rounded",
      "color": "#185FA5"
    },
    "backgroundOptions": {
      "color": "#E6F1FB"
    },
    "cornersDotOptions": {
      "type": "dot",
      "color": "#185FA5"
    },
    "qrOptions": {
      "errorCorrectionLevel": "H"
    } 
  }'

{
  "success": true,
  "meta": {
    "format": "png",
    "mimeType": "image/png",
    "width": 600,
    "height": 600,
    "type": "canvas",
    "data": "https://example.com",
    "project": "daveco",
    "sizeBytes": 38361,
    "durationMs": 217,
    "generatedAt": "2026-05-02T20:35:23.346Z",
    "errorCorrectionLevel": "H",
    "dotsType": "extra-rounded",
    "dotsColor": "#185FA5",
    "backgroundColor": "#E6F1FB",
    "hasImage": false,
    "margin": 20,
    "border": 10
  },
  "image": {
    "filename": "assets/images/daveco/600x600_185FA5_E6F1FB_daveco.png",
    "generated": "2026-05-02T20:35:23.346Z",
    "base64": "iVBORw0KGgoAAAANSUhEUgAAAlgAAAJYCAYAAAC+ZpjcAAAABmJLR0...",
    "dataUri": "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAlgAAAJY..."
  }
}```
</details>


### Pipe JSON via stdin

<details>
<summary>

```bash
echo '{
  "data": "https://example.com",
  "width": 300,
  "format": "png"
}' | docker run --rm -i rondomondo/qr-cli:latest

{
  "success": true,
  "meta": {
    "format": "png",
    "mimeType": "image/png",
    "width": 300,
    "height": 300,
    "type": "canvas",
    "data": "https://example.com",
    "sizeBytes": 1539,
    "durationMs": 152,
    "generatedAt": "2026-05-02T20:40:14.125Z",
    "errorCorrectionLevel": "Q",
    "dotsType": "square",
    "dotsColor": "#000000",
    "backgroundColor": "#ffffff",
    "hasImage": false,
    "margin": 0,
    "border": 0
  },
  "image": {
    "filename": "qr.png",
    "generated": "2026-05-02T20:40:14.125Z",
    "base64": "iVBORw0KGgoAAAANSUhEUgAAASwAAAEsCAYAAAB5fY51AAAABmJLR0...",
    "dataUri": "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAASwAAAEs..."
  }
}

Save the image to disk

docker run --rm rondomondo/qr-cli:latest --data="https://example.com" \
  | jq -r '.image.base64' \
  | base64 -d > qr.png

Examples

A few examples below to give you a taste. EXAMPLES.md has the full set covering every dot style, corner style, error correction level, and output format. Run them all in one go:

make examples

Full styling with logo (JSON blob)

docker run --rm rondomondo/qr-cli:latest \
  --json='{
    "data": "https://facebook.com",
    "width": 600, "height": 600,
    "format": "png", "border": 10, "margin": 20,
    "image": "https://upload.wikimedia.org/wikipedia/commons/5/51/Facebook_f_logo_%282019%29.svg",
    "imageOptions": { "crossOrigin": "anonymous", "margin": 10 },
    "qrOptions": { "errorCorrectionLevel": "H" },
    "dotsOptions": { "type": "extra-rounded", "color": "#185FA5" },
    "backgroundOptions": { "color": "#E6F1FB" },
    "cornersSquareOptions": { "type": "extra-rounded", "color": "#185FA5" },
    "cornersDotOptions": { "type": "dot", "color": "#185FA5" }
  }' \
  | jq -r '.image.base64' | base64 -d > qr.png

Dot styles (CLI flags)

docker run --rm rondomondo/qr-cli:latest \
  --data="https://example.com" --format=png \
  --border=10 --margin=10 \
  --dotsOptions.type=extra-rounded \
  --dotsOptions.color="#2B4D00" \
  --backgroundOptions.color="#D4F299" \
  | jq -r '.image.base64' | base64 -d > qr.png

Corner styles (JSON blob)

docker run --rm rondomondo/qr-cli:latest \
  --json='{"data":"https://example.com","width":400,"height":400,"format":"png",
    "border":10,"margin":10,
    "dotsOptions":{"color":"#064E3B","type":"rounded"},
    "cornersSquareOptions":{"color":"#064E3B","type":"extra-rounded"},
    "backgroundOptions":{"color":"#A7F3D0"}}' \
  | jq -r '.image.base64' | base64 -d > qr.png

See all skill equivalents for every example in EXAMPLES.md:

make skill-examples

/qr skill

If you use something like Claude Code, this repo ships a /qr skill that lets you generate QR codes in plain English directly from the chat panel.

Setup

The skill files live at ./.claude/skills/qr. And make skill-install will copy them to the correct place. Your CLI/Agent will pick them up automatically then. There is also a zipped version for simplicity in ./.claude/skills/qr.zip

Usage

/qr <url> [natural language options]

Colours, dot styles, sizes, and logos are all described in plain English:

/qr https://example.com
/qr https://example.com rounded royal blue on cream
/qr https://example.com extra-rounded midnight blue on ivory 500px
/qr https://example.com svg slate on white
/qr https://example.com extra-rounded #175EF0 on #E0E0E0 round corners dot corner dots high error correction 600px with logo https://example.com/logo.svg

What the skill does

1. Parses your intent (colour names, style keywords, size, format, logo URL).
2. Resolves ~30K English colour names to hex via colourmapper.
3. Calls scripts/qr-skill.sh, which wraps the Docker image.
4. Saves the image to assets/images/{project}/{width}x{height}_{dots}_{bg}_{project}.{format}.
5. Reports a summary with a clickable link and a fenced open command you can copy straight from the VS Code copy button:

open assets/images/default/600x600_175ef0_e0e0e0_default.png

Raw flags also pass straight through, so you can mix natural language and explicit options in the same command.

/qr skill examples

Three examples picked from make skill-examples to show the natural-language shorthand:

/qr https://example.com extra-rounded #2B4D00 on #D4F299

/qr https://example.com classy rounded #042C53 on #B5D4F4

/qr https://example.com rounded #5C3A00 on #FDE68A round corners dot corner dots

Skill quick-reference

See all skill equivalents for the examples

Tip:

make skill-examples

This prints a /qr skill command (and its natural-language shorthand) for every example in EXAMPLES.md.

Helper scripts

Output schema

{
  "success": true,
  "meta": {
    "format": "png",                        // output format
    "mimeType": "image/png",
    "width": 300,
    "height": 300,
    "type": "canvas",                       // qr-code-styling render type
    "data": "https://...",                  // the encoded string
    "project": "daveco",                    // project name if supplied, else omitted
    "sizeBytes": 12345,                     // raw image buffer size in bytes
    "durationMs": 42,                       // time taken to generate in ms
    "generatedAt": "2024-01-01T00:00:00Z", // UTC ISO 8601 timestamp
    "errorCorrectionLevel": "Q",
    "dotsType": "rounded",
    "dotsColor": "#0255c7",
    "backgroundColor": "#fdfbd4",
    "hasImage": false,
    "margin": 10,
    "border": 20                            // pixels added around the QR code
  },
  "image": {
    "filename": "assets/images/daveco/300x300_0255C7_FDFBD4_daveco.png",    // assets/images/{project}/{width}x{height}_{dots}_{bg}_{project}.{format})
    "generated": "2024-01-01T00:00:00Z",   // UTC ISO 8601 timestamp (same as meta.generatedAt)
    "base64": "<base64 string>",
    "dataUri": "data:image/png;base64,<base64 string>"
  }
}

On error (written to both stdout and stderr so jq pipelines can catch it):

{ "success": false, "error": "Missing required option: \"data\"" }

Useful jq extractions

# Save to disk, decoding base64
docker run --rm rondomondo/qr-cli:latest --data="https://example.com" \
  | jq -r '.image.base64' | base64 -d > qr.png

# One-liner: generate and save using the suggested filename (requires --project)
OUT=$(docker run --rm rondomondo/qr-cli:latest --data="https://example.com" --project=myapp --format=png)
mkdir -p $(dirname $(echo $OUT | jq -r '.image.filename'))
echo $OUT | jq -r '.image.base64' | base64 -d > $(echo $OUT | jq -r '.image.filename')

# Check success before using
if echo $OUT | jq -e '.success' > /dev/null; then
  echo $OUT | jq -r '.image.base64' | base64 -d > qr.png
else
  echo $OUT | jq -r '.error'
fi

# Print generation time
echo $OUT | jq '.meta.durationMs'

All supported options

These map 1:1 to the qr-code-styling API:

Gradient options (on dotsOptions, backgroundOptions, cornersSquareOptions, cornersDotOptions) must be supplied as JSON:

{
  "dotsOptions": {
    "gradient": {
      "type": "linear",
      "rotation": 0,
      "colorStops": [
        { "offset": 0, "color": "#000000" },
        { "offset": 1, "color": "#0255c7" }
      ]
    }
  }
}