900Slides

A free, local-first desktop presentation editor. An open-source alternative to PowerPoint and Google Slides that runs entirely on your own computer — no account, no subscription, no telemetry, no constant internet connection, and untouched parts of your .pptx files are preserved byte-for-byte.

900Slides is built for the people and communities priced out of subscription productivity software: classrooms, small businesses, researchers, public services, and community organizers who need reliable presentation tooling on an ordinary laptop, including when the Wi-Fi is down.

Download

The source is on the 0.4 development track. The release workflow builds platform artifacts on tagged releases and manual runs; check a successful run in GitHub Actions for downloads. A configured job is not evidence that an installer has been tested. See docs/RELEASES.md for installation and validation status.

Platform	Configured artifact	Validation still required
macOS	Ad-hoc signed .app	Target OS install and Gatekeeper flow; not notarized
Linux	.deb and .AppImage, built on Ubuntu 22.04	Clean supported systems and offline dependencies
Windows	NSIS installer including the offline WebView2 installer	Clean offline Windows installation; not code signed

The Windows offline bundle includes a browser runtime and is substantially larger than the app executable. The 16 MiB executable regression budget is not an installer-size or RAM claim. Supported older-device targets and outstanding tests are tracked in docs/LOW_RESOURCE_REQUIREMENTS.md.

Why it exists

Presentation software is basic working infrastructure — for teaching, running a small business, organizing a community, or publishing research. Many established tools work offline, but licensing, account setup, runtime requirements, and offline installation differ. 900 Labs builds open-source tools that stay useful with intermittent access and modest hardware. 900Slides is the presentation sibling in that family, and it is built to remain that way.

Features

Slide editing

• Slide organization: add, move up/down and delete slides, with undo. The final slide is retained; reordering and deletion persist when saving PPTX.

• Rich text in every text box: bold, italic, underline, strikethrough, super/subscript, inline code, links, headings (H1–H6), blockquotes, fenced code blocks with stepped line-range highlighting (1-3|4|5,7), and indent levels.

• Images and shapes: PNG, JPEG, GIF, WebP, and SVG, plus geometric shapes (rectangle, rounded rectangle, ellipse, triangle, line, arrow, right-arrow callout, five-point star). Objects can be moved and resized; geometric shapes have fill, outline, opacity, and shadow controls. Imported image crops and rotations render, but dedicated crop/rotation controls remain open.

• Tables up to 50 rows × 50 columns with text editing and row/column insertion and deletion. Imported fills, borders, header rows, cell alignment, and dimensions render; dedicated cell-formatting and row/column resize controls remain open.

• Charts (bar, column, line, area, pie, scatter) with an in-place data-table editor for categories, series, and values. Switch the chart type at any time.

Presenting

• Dual-display mode: a presenter window (controls, notes, timer, next-slide preview) drives a separate fullscreen audience window, synchronized live.
• Laser pointer (L), highlighter (H), and black/white Q&A slide (B / W) — keyboard navigation throughout.
• Projector filter panel to compensate for difficult projectors: invert, brightness, contrast, saturation, sepia, and hue-rotate, persisted per deck.

Animations & transitions

• Build-ins (fade, slide-in from any edge, appear, disappear) with an ordered build-sequence editor, revealed step-by-step on each click.
• Transitions between slides: none, fade, slide, push, wipe.
• Magic Move (morph) automatically interpolates position, size, rotation, and opacity for shapes that share a stable id across adjacent slides.
• Stepped code highlighting advances through code-block ranges during a talk.

Templates & structure

• Six built-in templates (Default, Educator, Pitch, Conference Talk, Community Update, Photo Essay), each with its own theme, slide master, and named layouts.
• Aspect ratios 16:9, 4:3, and 16:10, with a toolbar picker.
• Named, collapsible sections, rich-text speaker notes, find and replace (Cmd/Ctrl+F), a keyboard-shortcuts dialog (?), and a high-contrast theme toggle.

Formats & fidelity

• Lossless PPTX: unedited parts of the package are carried as opaque objects and re-emitted unchanged; save regenerates only the slides you touched. A per-slide loss ledger warns you about content that is preserved but not yet editable (e.g. SmartArt).
• ODP import and export library (OpenDocument Presentation). The current desktop file chooser exposes PPTX; ODP UI integration remains open.
• Deterministic export to SVG (per slide), PNG (2× retina, per slide), and PDF (entire deck) — fully offline, identical inputs yield byte-identical output.
• Bundled render/export fonts (Inter, Source Serif 4, JetBrains Mono) reduce dependence on installed fonts. Editor substitution and additional script coverage still require qualification.

Private & resilient

• No account, no telemetry, no network calls — the application is fully offline.
• Image sanitization on ingest: EXIF and other metadata are stripped, only allowlisted formats are accepted, and embedded SVG is scrubbed of scripts, event handlers, and unsafe URL references.
• Offline spell-check (en-US) with red squiggles, right-click suggestions, and a personal dictionary that persists across sessions.
• Safer file workflow: Save reuses the current PPTX path; Save As creates a copy. New, Open, and Quit protect unsaved work with Save / Discard / Cancel.
• Crash recovery: text, table cells, and notes commit while you type; debounced recovery snapshots and a startup recovery prompt help recover work.
• Bounded preview caches: viewport-aware thumbnails release offscreen SVGs and use a byte budget. The active deck and its source media still require RAM.
• Local history, comments, and document accessibility checks are available. The accessibility score is a heuristic, not a WCAG conformance assessment.

How to use it

1. Choose New to start from one of the six built-in templates, or Open to load an existing .pptx file.
2. Choose Text Box from the toolbar or Insert menu, then click the canvas to place one. To edit an existing text box, select it and press Enter or double-click it. Edits commit automatically while typing, with an explicit flush before saving or switching slides. Undo with the toolbar button.
3. Insert an image from the toolbar (sanitized on the way in), or choose Shape and a geometry from the picker. Click the canvas for a default shape, or click-drag to place it at explicit bounds. Images and shapes render on the canvas and can be moved and restyled.
4. Insert a table from the toolbar and click cells to edit, or insert a chart and double-click it to edit its data. Content 900Slides cannot yet edit (e.g. SmartArt) appears as a labelled placeholder — preserved on save but not modifiable.
5. Choose Save to write a .pptx, or use the Export menu for SVG, PNG, or PDF. For imported PPTX, save patches supported edited parts and preserves untouched package content; ODP conversion has a separate compatibility scope.
6. Choose Present to open dual-display mode: a presenter window and a fullscreen audience window. Navigate with arrow keys, space, Home, End, and Escape. Press B / W for a black/white Q&A slide, L for the laser pointer, and H for the highlighter.

Recovery

After an edit, 900Slides waits for activity to settle, then writes a recovery snapshot to the app data directory. Recovery files are separate from the file you opened, and a normal save retires the corresponding snapshot. If recovery snapshots are found at startup, the app lists them newest first — restore one, discard one, or skip to a new deck.

What it does not do (yet)

The next milestone is a dependable everyday editor on supported modest hardware. These remain open acceptance gaps (roadmap):

• Verified 2 GB / 4 GB device performance and clean offline installation on Windows/Linux.
• Desktop ODP controls, slide duplication, full mixed-style text editing, and broader PowerPoint/LibreOffice interoperability coverage, master-layout fidelity, and clear font substitution reporting.
• Complete image alt-text editing, keyboard/screen-reader audits, localized UI, and RTL/CJK validation. The current UI and spell checker are English-first.
• A notarized macOS distribution and a signed Windows installer.
• Collaboration, mobile/web clients, and on-device AI features remain deferred.

Build from source

Prerequisites:

• Rust 1.92.0, pinned by rust-toolchain.toml
• Node.js 20.19 or newer, 22.12 or newer, or 24 or newer
• The Tauri v2 system prerequisites

git clone https://github.com/900Labs/900Slides.git
cd 900Slides
npm ci --prefix apps/desktop
npm run tauri:dev --prefix apps/desktop

To produce a release bundle:

npm run tauri:build --prefix apps/desktop

The standalone Tauri workspace owns the release profile used for distributable builds: size optimization, link-time optimization, one codegen unit, stripped symbols, and abort-on-panic. The size gate runs the full Tauri build so the frontend is rebuilt from source, the distributable custom-protocol feature is enabled, and the resulting target executable is checked against the maintained 16 MiB regression budget:

./scripts/verify-wave22.sh

Passing a binary path checks an already packaged executable without rebuilding. No-argument mode requires installed npm dependencies plus the platform's Tauri system prerequisites. Plain cargo build --release is a development-protocol build and is not the representative release-size measurement.

Validate the source

After installing the Tauri prerequisites for your platform, run the source checks:

./scripts/verify-local.sh

This runs workspace and standalone desktop formatting, clippy and tests, frontend type-check, unit tests, production frontend build, and the privacy gate. Complete the native smoke test with npm run tauri:dev --prefix apps/desktop. Run the public-release privacy gate before publishing or changing repository visibility:

./scripts/verify-public-release.sh

Repository layout

A Rust workspace of 11 library crates plus a Svelte 5 / Tauri v2 desktop app:

apps/desktop/             Desktop UI and Tauri command boundary
crates/slides-core/       Deck model, commands, undo, theme
crates/slides-pptx/       PPTX load and save (native format)
crates/slides-odp/        ODP (OpenDocument Presentation) import and export
crates/slides-pdf/        SVG, PNG, and PDF export
crates/slides-render/     Deterministic slide rendering to SVG
crates/slides-animation/  Deterministic build-in timeline and CSS playback
crates/slides-chart/      Chart data model and deterministic SVG previews
crates/slides-spell/      Offline en-US spell-check and suggestions
crates/slides-media/      Image ingest, EXIF strip, MIME allowlist, SVG sanitize
crates/slides-i18n/       Locale and accessibility helpers (stub)
crates/slides-fixtures/   Sanitized generated fixtures only (stub)

See the Roadmap for the full feature trajectory and the Competitive analysis for the research that informed it.

Quality gate

Run the complete local gate before opening a pull request:

./scripts/verify-local.sh

The workspace test suite is 300+ Rust tests, zero clippy warnings, and a clean svelte-check. The Rust suite includes generated PPTX round-trip tests that assert untouched parts are byte-identical after edits, determinism tests for the renderer, sanitizer and allowlist tests for image ingest and link URLs, and table/chart invariant and command round-trip tests.

Contributing and support

• Contributing guide
• Support guide
• Security policy

Bug reports, sanitized compatibility fixtures made with invented data, translations, documentation improvements, and focused performance work are all welcome.

License

900Slides is licensed under the Apache License 2.0. See LICENSE.