Canonical Recipes

Rendro ships canonical recipes on the three-rung escape-hatch pattern (document/2 → page_template/1 → sections/2). This guide includes five rendered gallery entries, including a branded invoice variant, so you can see the launch fixtures while still using canonical recipe defaults in code.

The capabilities claimed in this guide are bounded by priv/support_matrix.json. Supported capabilities are backed by on-disk proof in the corresponding evidence test files. Claims that exceed the support matrix are not made here.

Rendered Gallery

These previews are rendered by Rendro from curated deterministic recipe fixtures and recorded in assets/rendro/artifacts.json.

Source PDFs and the self-rendered manual are byte-checked by the required docs contract. PNG rasters are regenerated and hash-checked in the pinned pdfium-render advisory lane. pdfium-render rasters are render proof, not GUI-viewer proof. Launch fixtures may use opt-in table polish; canonical recipe defaults remain unchanged.

Invoice

Standard invoice from Elixir data through the canonical Invoice recipe.

• Source PDF SHA-256: fc65ac5688462a77e1cc3cdfd8cb25e8ac1d61677d430615443c23f565068105
• PNG SHA-256: 8acf5472e4c7a7ec6d04843464536b3f291e8cfc0d2c7fe8040913af4e648988

Branded Invoice

Branded invoice with registered font and logo assets.

• Source PDF SHA-256: 9bc4a0ea94e2a7cb09dbeeaf5f57b24f624a34a2c7d8012343bca1c66c8e95c9
• PNG SHA-256: 3618e386c02b622dddb785ead24843481aa963e91653614aeab22287354138b5

Statement

Multi-page statement with carried-forward balances and running page numbers.

• Source PDF SHA-256: fa4fd6f3d84ccdccc8a1812c0212a9b17820cd25ffb615519154e9dd3792b835
• PNG SHA-256: ec13a842b4ea48308ec682f4765c17fa3b70f75efb58739c3f9eb1a6d8963ec0

Receipt / Report

Receipt recipe scaled into a multi-page tabular report.

• Source PDF SHA-256: 68f3a44f655c4783bc9bd94ad3c37675edb09cfbe92009b2a54e4a35a91258b5
• PNG SHA-256: c2af63ac8460c85f8eb51240567d06ab71b72fd69be337bc165884f4af98c1c4

Certificate

Landscape certificate with a Path-backed, geometry-derived border frame.

• Source PDF SHA-256: 51b43c00c1e7afba093c6f6a682630576c639fb65912f504ddc9c6c6db0d3c95
• PNG SHA-256: 7194ebe35228f4026cc804b0b38913545ef997335d08f6d579f5d450a5c3fcf4

Self-Rendered Manual

Rendro also renders its own compact launch manual: manual.pdf.

SHA-256: a9f1a241c3fb331ad5522d905af8acf26d9848b8862cb9a6f3e4033c3ee1dc94

Statement

A multi-page billing statement with running "Page X of Y" footers and automatic carried-forward / brought-forward running balances.

Support matrix row: statement (backed by test/rendro/recipes/statement_test.exs)

Supported capabilities:

Zero-to-one

# docs-contract: recipes-statement-document
data = %{
  period: %{from: ~D[2026-05-01], to: ~D[2026-05-31]},
  account: %{name: "Acme Corp"},
  opening_balance: Decimal.new("1000.00"),
  lines: [
    %{date: ~D[2026-05-02], description: "Invoice #1", amount: Decimal.new("500.00")},
    %{date: ~D[2026-05-15], description: "Payment", amount: Decimal.new("-200.00")}
  ]
}

doc = Rendro.Recipes.Statement.document(data)
assert doc.page_template == :statement
assert %Rendro.Document{} = doc

{:ok, pdf} = Rendro.render(doc, deterministic: true)
assert binary_part(pdf, 0, 5) == "%PDF-"

Escape-hatch (page_template + sections)

# docs-contract: recipes-statement-escape-hatch
data = %{
  period: %{from: ~D[2026-06-01], to: ~D[2026-06-30]},
  account: %{name: "Beta LLC"},
  opening_balance: Decimal.new("500.00"),
  lines: [
    %{date: ~D[2026-06-05], description: "Service fee", amount: Decimal.new("150.00")}
  ]
}

template = Rendro.Recipes.Statement.page_template()
sections = Rendro.Recipes.Statement.sections(data)

assert template.name == :statement
assert is_list(sections)
assert length(sections) > 0

Data contract

Required keys:

• :period — %{from: Date.t(), to: Date.t()}
• :account — %{name: String.t()}
• :opening_balance — Decimal.t() (Float raises an instructive ArgumentError)
• :lines — [%{date: Date.t(), description: String.t(), amount: Decimal.t()}]

Optional keys:

• :closing_balance — Decimal.t() (validated against the running fold)
• :summary — caller-supplied summary map

Receipt / Report

A payment receipt that scales from one page to N pages. Multi-page is just a receipt whose line items overflow — column headers repeat on every page via per-page table blocks; "Page X of Y" appears in the running footer.

Support matrix row: receipt_report (backed by test/rendro/recipes/receipt_test.exs)

Supported capabilities:

Zero-to-one

# docs-contract: recipes-receipt-document
data = %{
  title: "Payment Receipt",
  date: ~D[2026-05-29],
  customer: %{name: "Acme Corp"},
  lines: [
    %{description: "Widget A", amount: Decimal.new("29.99")},
    %{description: "Widget B", amount: Decimal.new("49.99")}
  ],
  totals: %{subtotal: Decimal.new("79.98"), total: Decimal.new("79.98")}
}

doc = Rendro.Recipes.Receipt.document(data)
assert doc.page_template == :receipt
assert %Rendro.Document{} = doc

{:ok, pdf} = Rendro.render(doc, deterministic: true)
assert binary_part(pdf, 0, 5) == "%PDF-"

Escape-hatch (page_template + sections)

# docs-contract: recipes-receipt-escape-hatch
data = %{
  title: "Service Invoice",
  date: ~D[2026-06-01],
  customer: %{name: "Beta LLC"},
  lines: [
    %{description: "Consulting", amount: Decimal.new("1200.00")}
  ]
}

template = Rendro.Recipes.Receipt.page_template()
sections = Rendro.Recipes.Receipt.sections(data)

assert template.name == :receipt
assert is_list(sections)
assert length(sections) > 0

Data contract

Required keys:

• :title — String.t()
• :date — Date.t()
• :customer — %{name: String.t()}
• :lines — [%{description: String.t(), amount: Decimal.t()}]

Optional keys:

• :totals — %{subtotal: Decimal.t(), total: Decimal.t()} (validated when present)

Certificate

A geometry-derived completion, compliance, or award certificate. All region coordinates are computed from template geometry — zero hardcoded A4 numerics. The default orientation is landscape A4 (classic diploma look). Portrait is reachable via orientation: :portrait. Branding is optional.

Support matrix row: certificate (backed by test/rendro/recipes/certificate_test.exs)

Supported capabilities:

Zero-to-one

# docs-contract: recipes-certificate-document
data = %{
  title: "Certificate of Completion",
  recipient: "Jane Smith",
  date: ~D[2026-05-29],
  body: "For outstanding contribution to deterministic PDF generation.",
  seal_line: "Authorized Signature"
}

doc = Rendro.Recipes.Certificate.document(data)
assert doc.page_template == :certificate
assert %Rendro.Document{} = doc

{:ok, pdf} = Rendro.render(doc, deterministic: true)
assert binary_part(pdf, 0, 5) == "%PDF-"

Escape-hatch (page_template + sections)

# docs-contract: recipes-certificate-escape-hatch
data = %{
  title: "Award of Excellence",
  recipient: "Alex Chen",
  date: ~D[2026-06-15]
}

template = Rendro.Recipes.Certificate.page_template()
sections = Rendro.Recipes.Certificate.sections(data)

# Certificate uses geometry-derived layout with a single body region
assert template.name == :certificate
assert template.width > template.height
assert is_list(sections)
assert length(sections) > 0

Data contract

Required keys:

• :title — String.t()
• :recipient — String.t()
• :date — Date.t()

Optional keys:

• :body — String.t() (body statement, default "", must be ≤ 2000 bytes)
• :seal_line — String.t() (signature / seal line, default "")
• :brand — %{font_name: atom(), logo_name: atom()} (branded output)

Invoice and Branded Invoice

Invoice and BrandedInvoice are the foundational Rendro recipes covering standard invoice and branded invoice generation with a registered font and logo asset.

For full documentation on Invoice and BrandedInvoice — including font/asset registration, the three-rung composition pattern, failure diagnostics, and verified runnable examples — see guides/branding.md.

The support matrix has no separate invoice or branded_invoice rows because the branding surface is already covered by the guide and recipe moduledocs.

Scope boundaries

None of the recipes in this guide claim:

• Signing or signing preparation — see Rendro.Sign for the supported signing path
• Blanket compliance or viewer-promotion narratives — see priv/support_matrix.json for the exact supported surface
• Viewer-specific rendering guarantees — see guides/viewer_evidence.md for recorded per-viewer behavior