Beamer

Beamer Skill

LaTeX Beamer compiles .tex source into HTML-free, presentation-quality PDF slides. It is the standard for academic thesis defenses, conference talks, and any deck where typographic and mathematical fidelity matter. This skill teaches you how to author Beamer decks from scratch, convert existing Markdown/Obsidian drafts, compile them reliably via latexmk, and extend the theme system without inventing new mechanisms.

The companion skill is marp (Markdown-based slides via marp-cli). They share template names (basic, academic, thesis-defense, research-update) so the same content shape can be authored in either format depending on the venue — Markdown for fast iteration and live preview, Beamer for academic submission.

When to read what

• New deck from scratch → stay in this file (Workflow A) and pick a template from assets/templates/.
• Convert an existing Markdown/Obsidian draft → Workflow B, then references/authoring.md for frame mapping.
• Build to PDF, fix compiler errors, set up continuous compilation → Workflow C, then references/build-and-config.md.
• Build or extend a theme (custom brand or institution) → Workflow D, then references/authoring.md for Beamer-specific selectors. Start from assets/themes/beamerthemeMinimal.sty.
• Thesis defense structure (bachelor/master defense shape — agenda, RQs, methodology, results, discussion, Q&A) → references/thesis-defense-checklist.md.

The reference files are small on purpose. Read the one you need; don't preload all of them.

Quick reference card

Every Beamer deck begins with a class declaration and frontmatter-like preamble:

\documentclass[aspectratio=169,12pt]{beamer}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[ngerman,english]{babel}   % English primary, German secondary for thesis context
\usepackage{graphicx}
\usepackage{booktabs}
\usepackage{listings}
\usepackage{hyperref}

\usetheme{Minimal}                        % or default, Madrid, Berlin, Szeged, Frankfurt
% \usepackage{./preamble/common}      % when using the bundled common preamble

\title{<TITLE>}
\subtitle{Telemetry Reliability under Automated Canary Remediation}
\author{<NAME>}
\institute{<INSTITUTE>}
\date{\today}

\begin{document}

\begin{frame}
  \titlepage
\end{frame}

\begin{frame}{Section heading}
  \begin{itemize}
    \item Bullet
    \item Bullet with \textbf{emphasis}
  \end{itemize}
  \note{Speaker note for this frame.}
\end{frame}

\end{document}

Each \begin{frame}{Title} … \end{frame} pair is one slide. \note{...} blocks become presenter notes (rendered via the beamer show notes mode).

Construct	Effect
\begin{block}{Heading}…\end{block}	Highlighted text block with a title
\begin{alertblock}{Heading}…\end{alertblock}	Red-toned variant for warnings/key findings
\begin{exampleblock}{Heading}…\end{exampleblock}	Green-toned variant for examples
\begin{columns}\begin{column}{0.5\textwidth}…\end{column}\end{columns}	Multi-column layout
\pause / \onslide<2->	Reveal content incrementally
\includegraphics[width=0.7\textwidth]{figures/foo}	Insert figure
\frametitle{...}	Set the frame title from inside the frame

Built-in themes worth knowing: default (clean, minimal), Madrid (blue with header bar — popular for academic), Berlin (with navigation bullets), Szeged (clean horizontal nav), Frankfurt (vertical nav). The bundled Minimal theme is a token-driven extension of Madrid that matches the marp minimal companion theme — one source of brand truth across both formats.

Workflow A: Author a new deck

1. Pick a template based on context:
   • assets/templates/basic.tex — generic deck, default theme, 3-5 frames for a quick talk.
   • assets/templates/academic.tex — conference/seminar talk shape (motivation → method → result → conclusion), Madrid theme.
   • assets/templates/thesis-defense.tex — full thesis-defense skeleton (intro · RQs · methodology · results · discussion · conclusion · backup). Mirrors marp/assets/templates/thesis-defense.md content. Use only for the defense itself.
   • assets/templates/research-update.tex — 5-8 frame supervisor check-in: what we tested · key result · problem/finding · next step · ask.
   • assets/templates/sprint-review.tex — agile sprint review/demo: goal · shipped · demo · metrics · retro · next sprint · asks.
   • assets/templates/tech-talk.tex — engineering talk: problem · prior art · design · implementation · live demo · results · lessons.
   • assets/templates/lightning-talk.tex — 5-minute talk: hook · the one point · evidence · takeaway.
   • assets/templates/kickoff.tex — project kickoff: problem · goals · non-goals · scope · solution · timeline · stakeholders · risks · decisions.
2. Confirm the output path with the user before writing. Sensible defaults — but always ask if you don't know:
   • Thesis-related decks → <vault>/<thesis-folder>/Presentations/<YYYY-MM-DD>-<slug>/main.tex
   • Conference/seminar submissions → wherever the project source already lives
   • Project / work decks → wherever the project source lives
   • Anything else → ask. Do not invent a path silently.
3. Apply the slide-budget rule of thumb. Roughly one frame per minute of speaking time:
   • Thesis defense (~15 min talk) → 12-15 content frames plus title + backup section.
   • Supervisor check-in (~5-7 min) → 5-8 frames.
   • Sprint review (~10-15 min) → 8-12 frames.
   • Tech talk (~30 min) → ~20 frames + backup.
   • Lightning talk (~3-5 min) → 3-6 frames. If the content forces 30+ frames for a 15-min slot, push back: suggest cutting or splitting before drafting.
4. Write the deck. One \begin{frame}{Title}…\end{frame} per slide. Use \begin{itemize} for bullets (3-5 per frame). Put speaker notes in \note{...} blocks at the end of the frame.
5. Compile to verify. Run latexmk -pdf -interaction=nonstopmode -halt-on-error main.tex after the first three frames are drafted — catches preamble issues before they cascade into 100 errors. See references/build-and-config.md for the build pipeline.

Workflow B: Convert an existing Markdown or Obsidian draft into Beamer

1. Read the source. Identify H1 (title), H2 sections, prose paragraphs, lists, code blocks.
2. Default mapping:
   • H1 → title page (\titlepage)
   • H2 → new frame title (\begin{frame}{H2 text})
   • Lists → \begin{itemize}…\end{itemize}
   • Code fences → \begin{lstlisting}…\end{lstlisting} (load listings package)
   • Block quotes → \begin{quote}…\end{quote} or a colored \begin{block}
   • Inline emphasis: **bold** → \textbf{...}, *italic* → \emph{...}, `code` → \texttt{...}
3. Special characters need escaping. _, &, %, #, $, {, } → \_, \&, \%, \#, \$, \{, \}. Backticks become straight quotes or use the listings package for verbatim text.
4. Figures. Markdown image paths (![](./figures/foo.png)) → \includegraphics[width=...]{figures/foo} (omit extension; Beamer resolves it). Keep figures under figures/ next to the .tex for the bundled .latexmkrc discovery.
5. Iterate. Compile after each section is converted; LaTeX is much less forgiving than Markdown — fix as you go.

Workflow C: Build and export

Local prereq: latexmk and a TeX distribution (pdflatex). Both are pre-installed on this system.

# One-shot compile
latexmk -pdf -interaction=nonstopmode -halt-on-error main.tex

# Continuous compile + preview (delegate to presentation-builder subagent)
latexmk -pdf -pvc main.tex

# Clean intermediate files (.aux, .log, .nav, .snm, .out, .toc, .vrb)
latexmk -c

# Full clean (also removes the .pdf)
latexmk -C

-interaction=nonstopmode makes LaTeX exit on errors instead of dropping into an interactive prompt — essential for scripted compilation. -halt-on-error stops on the first error rather than trying to recover (which produces 80 cascading errors).

For multi-output batch builds (PDF for distribution + handout-mode PDF + speaker-notes PDF), see references/build-and-config.md.

After compile succeeds, invoke the slide-overflow-check skill on the output PDF before reporting completion. It complements LaTeX's own Overfull \hbox warnings: those catch typesetting overruns inside a single line, while this check catches layout overruns — frame contents that exceed the canvas vertically and collide with the footer / page-number rail. One-line invocation:

python3 ${CLAUDE_PLUGIN_ROOT}/skills/slide-overflow-check/scripts/check_overflow.py main.pdf

If the check flags a frame, the right fix is usually \small / \footnotesize for the body, or splitting the frame across two with \framebreak or a manual continuation. See the slide-overflow-check SKILL.md for tuning flags (Beamer themes with thick footer bands like Madrid may want --footer-clearance 30).

Workflow D: Create or customize a theme

Beamer themes are LaTeX style packages (.sty files) named beamertheme<Name>.sty. The bundled assets/themes/beamerthemeMinimal.sty is a token-surface extension of Madrid: colors, font choices, and footer text are defined as macros at the top of the file so brand-specific values can be confirmed once and propagate to every deck that uses \usetheme{Minimal}.

For brand-consistent themes across multiple formats, use the theme-authoring skill (/new-theme <brand.yaml>) instead of editing this minimal starter directly. It generates beamertheme<Pascal>.sty (with BrandPrimary/BrandSecondary/etc. token macros), plus the matching Marp/Slidev/pptx artifacts, from a single brand.yaml. The minimal starter is still the right entry point if you only need Beamer or want full hand-control over the LaTeX.

1. Start from assets/themes/beamerthemeMinimal.sty — it's a commented stub. Override the brand-specific values (BrandPrimary, BrandSecondary, BrandAccent, footer text) with your own.
2. Register the theme. Beamer requires the .sty file on TEXINPUTS. Three ways:
   • Copy it next to the .tex source (simplest, recommended for self-contained decks).
   • Put it in ~/texmf/tex/latex/local/ and run texhash.
   • Set TEXINPUTS=./themes:$TEXINPUTS before invoking latexmk.
3. Reference it from the deck. \usetheme{Minimal} (the suffix after beamertheme, NOT the filename).
4. Iterate. Edit the .sty, rerun latexmk -pdf main.tex. With latexmk -pvc the rebuild is automatic.

Theme resolution

Themes resolve in two locations, in order:

1. User themes — ${XDG_DATA_HOME:-$HOME/.local/share}/presentation-kit/themes/beamer/beamertheme*.sty. Survives plugin updates.
2. Bundled themes — assets/themes/beamertheme*.sty relative to this skill (e.g. beamerthemeMinimal.sty).

User themes shadow bundled ones when the basename matches. When listing themes to the user, prefix each with (user) or (bundled) so the active source is unambiguous. Copy the resolved file next to the .tex source before compiling — Beamer needs to find it on TEXINPUTS, and the user's project directory is the safest place.

Save the current working theme as a reusable user theme:

bash scripts/save-theme.sh beamer <name> ./beamerthemeFoo.sty
# add --force before "beamer" to overwrite an existing user theme

Full per-package selector reference (\setbeamercolor, \setbeamerfont, \setbeamertemplate) lives in references/authoring.md under "Theme internals".

Common pitfalls

• Unescaped underscores in identifiers, URLs, or filenames — \_ everywhere or wrap in \texttt{}.
• Forgetting [fragile] on frames with lstlisting — \begin{frame}[fragile]{Title} is required when the frame contains verbatim content.
• \usetheme{...} mismatch with the .sty filename — the argument is the suffix after beamertheme, not the file name. beamerthemeMinimal.sty → \usetheme{Minimal}.
• latexmk not detecting a re-run — when you add a \label referenced before its definition, run twice or rely on latexmk which handles it automatically.
• Aspect ratio mismatch with a venue's projector — declare it in \documentclass[aspectratio=169]{beamer} (or 43 for 4:3). Mixing breaks template layouts.
• Trying to use Markdown-style inline formatting — **bold** is literal in LaTeX. Use \textbf{...}.
• Missing fonts for non-default themes — themes like Madrid use the default Computer Modern; the bundled Minimal theme inherits Madrid's fonts. If a custom theme references a font you don't have installed, LaTeX falls back silently and the deck looks wrong.

Quality checklist before delivering

• Title page renders correctly (\title, \author, \institute, \date all populated)
• Page numbers / pagination visible on content frames (theme-dependent — verify visually)
• All figures resolve (no LaTeX Warning: File \...' not found` in the log)
• No LaTeX Warning: Reference \...' on page ... undefined(runlatexmktwice or once with-pvc` to settle)
• No Overfull \hbox warnings on critical text frames (content runs off-slide)
• Speaker notes present in \note{...} blocks for every content frame (skip title/section dividers)
• Aspect ratio matches the venue's projector
• Backup section present for thesis defense (Q&A material parked there, not in the main flow)
• slide-overflow-check ran clean against the output PDF (catches layout overruns the LaTeX log misses). See the companion slide-overflow-check skill.