Rendered from CHANGELOG.md in the repository — edit it there.

Changelog

All notable changes to Slicer Engine are documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

This file is the single source of truth for release notes. It is embedded into every build (CLI, WS server, WASM/UI, desktop) at compile time and republished verbatim as the body of each GitHub Release. See RELEASING.md for the workflow that keeps those in sync.

[Unreleased]

[0.6.0] - 2026-10-01

Your models get a library, and your prints come off faster. Every model you've plated is now one keypress away, and the stock profiles take nearly ten minutes off a Benchy.

Highlights

• Library — every model you've ever plated, kept once with a picture. Press L beside a plate and pick one to drop it on. On desktop it can watch your folders; on iPad it's a folder in Files.
• Faster by default — quicker stock speeds take a Benchy from 47 to 37 minutes, at the same layer height, walls and infill.
• Smarter packing — Place objects nests parts by shape and height, so one can tuck under another's overhang.

Added

• Drag to move, box to select — pick a part up in one gesture; Shift-drag selects everything in the box. Long-press builds a selection on touch and pen.
• Export a plate as 3MF — right-click its tab or an empty spot on the bed.
• Read the G-code beside the plate — click a line and the preview jumps to it; scrub the preview and the text follows.
• Slicing tells you more — filament weight and cost beside the print time, and Slice turns into Cancel while it works.
• Search all of Settings — pages, preferences, profiles and every setting.
• Per-printer material tweaks — let one machine treat a material differently without copying the filament for it.
• More from the keyboard — ⌘/Ctrl + Enter slices, ⌘/Ctrl + D duplicates, Z zooms to a part, arrows nudge, and removing a model can be undone.
• Send feedback from the Help menu.

Changed

• A calmer, floating layout — print settings float over the plate instead of squeezing it, and plate tabs look like tabs, with a searchable list of them all.
• Hidden walls keep their pace — inner walls and internal solid infill have their own speeds, so slowing the outer wall for a better finish costs less.
• Cleaner wall starts — travel brakes gently where it lands on an outer wall.
• Built-in profiles are editable in place, with Restore defaults to go back, and the setup wizards ask one thing per screen.
• Messages appear beside the work they're about, not in a corner over your plate.
• The app starts faster and fits a fingertip on phones and tablets.

Fixed

• The same model always slices to the same G-code.
• Curves print smooth — no more stutter or facets on vases and large arcs.
• Rotated and auto-oriented parts sit on the bed, and turn where they stand.
• Adding models works on iPad — the plate's add button no longer greys out .stl and .3mf files.
• Links open in your browser from the desktop and iPad apps.
• Upload & print always confirms first, and never sends a stale file.

Contributors

Thanks to @max-scopp, who shipped this release end to end — the library, the floating layout and the new plate tools all landed in this cycle.

[0.5.0] - 2026-09-16

Support structures grow up, thin features finally print, and a plate stops being a file. This release makes overhangs printable without hand-holding, fixes the walls that quietly vanished on anything rotated or narrow, and turns workplates into real tabs that survive closing the app.

Highlights

• Supports that hold, not hint — sloped overhangs get real columns, the gap closes to 0.35 mm, islands print as continuous loops, and a brush lets you enforce or block support anywhere the automatic rule guesses wrong.
• Thin features print, at any angle — ribs, fins and dividers survive a wide nozzle and slice identically turned 45° as flat. A card caddy that lost 42 % of its dividers when rotated now lays the same length at every angle.
• Workplates are tabs — open several plates at once, switch between them in any runtime, and find them arranged exactly as you left them after a restart.

Added

Supports

• Paint support where you want it — B picks up a brush to enforce support regardless of angle or block it entirely. Support Auto turns the angle rule off, for plates supported only where painted.
• Support line width joins the other per-role widths, without dragging the raft's deliberately coarser bead along with it.

Printing and output

• Fuzzy skin — an outer-wall texture that roughs the surface with a small random jitter. Tunable thickness and spacing, off by default, purely cosmetic.
• Pause and colour change at a layer — mark any layer in the preview to stop for an insert or a filament swap. Emits Marlin M0/M600, Klipper PAUSE or RepRap M226.
• Bed mesh levelling — bed_mesh_mode emits BED_MESH_CALIBRATE or G29/M420 S1 at print start, off by default. bed_mesh_adaptive bounds recalibration to the print's own footprint.
• Minimum layer time — min_layer_time_s slows a short layer so it has time to cool, clamped at min_print_speed (10 mm/s). First layer exempt, off by default.
• Acceleration for every role — inner wall, sparse and solid infill, gap fill, support and travel each carry their own limit, all shipping with non-zero defaults (10 000 mm/s² baseline, 15 000 for travel, 1 000 for first layer and bridges). Set any to 0 for the old defer-to-firmware behaviour.

Printers and plates

• Your Klipper printer sets itself up — detection reads the machine's own configuration: build volume, kinematics, nozzle, velocity and acceleration limits, pressure advance, firmware retraction, object cancellation and which start macros it uses. What we read from your printer shows every value and the printer.cfg section it came from.
• The wizard only asks what your printer can't answer — a short question or two after detection, each with an answer already picked and a line saying why.
• Two faster presets, and a CoreXY to run them on — High Speed (200 mm/s) and Maximum (300 mm/s, 30 000 mm/s²), both holding the outer wall and top surface back. A Generic CoreXY 350 mm preset carries the machine side.
• Sync to profile — review every setting a plate has changed against its profiles, side by side like a diff, and write the ones you keep straight back.
• See when a colleague changes the plate you are on — on a shared server, saving tells everyone else looking at it. Nothing reloads by itself.
• Open a model straight from another app — Cold Crabby registers for .stl, .obj and .3mf on Windows, macOS, Linux, iPhone and iPad. The model joins the plate you have open rather than replacing it.

The app

• An outline for the settings panel — press the list button or Ctrl/⌘ + Shift + O for a table of contents: every section and every setting by name, including what the panel folds away. The profile editors get the same rail with a filter box.
• Settings start calm and open all the way — each section shows what a print depends on, then an Advanced row that expands in place; a second press reveals Expert. Process drops from eleven sections to seven. Search still reaches everything.
• Every setting says what it measures — units, sensible steps and fractions read as percentages, so a nozzle steps by 5 °C rather than to 210.01.
• The preview re-slices itself, when that's worth doing — Automatic re-slices a second after you stop, but only while slices stay under 5 s, timed per plate.
• The slice dock says how long the print will take, read from the G-code's own commanded speeds.
• Hold + or − to run a number up or down, accelerating the longer you hold.
• Thumbnails can match the 3D view's look — Settings → General → Thumbnail look renders with the viewport's shading and shadow. Plain by default.

Changed

• Better infill and surface defaults — sparse infill is now TPMS-D at 20 %, which carries load in every direction, and top and bottom surfaces are rectilinear for an even, evenly-pressed face. First layer slows to 25 mm/s.
• Smooth-bridge defaults — bridges print at 10 mm/s with 1.5× flow so their strands fuse into a continuous floor before they sag.
• Dynamic overhang speed actually slows the transition — the 25–50 % band a curved hull spends many layers inside is now stated as a percentage of the preset's own wall speed, and any band can be expressed that way. Slow down curled perimeters no longer needs a hand-tuned override to engage.
• Auto-orient goes for the biggest face that actually touches the bed — real bed contact instead of every downward-facing surface, so flat-bottomed parts stop being tipped onto a corner. A pose too tall for the machine ranks last.
• A thin rib prints as the wall it is — wall speed, wall acceleration, wall colour, instead of the gentle gap-fill treatment.
• Short hops inside a part no longer retract — under 5 mm and crossing no wall, the retract, Z-hop and prime are skipped; where there is a way round, the hop travels back over its own beads so what it drools lands on the part. One rib-heavy model loses 85 % of its retractions.
• Material settings live with the filament — flow ratio, maximum volumetric speed and pressure advance move from Process, where a profile switch used to overwrite your per-spool calibration. A new Material group collects what the spool is.
• Every speed reads in mm/s, travel and retraction included; press the unit to switch the whole panel to mm/min. The stored value never changes.
• Gravity is on by default, and remembered.
• Filament type is a list, offering the materials firmware and other slicers read back — while keeping whatever a vendor profile already carries.
• Deleting a profile confirms inline instead of asking you to type its name.
• Touch targets meet the 44 pt floor across tabs, steppers, menus and the viewport cube, and the page no longer zooms out from under a pinch.
• The G-code editor follows the app theme.

Fixed

Walls and travel

• Turning a model no longer changes how it slices — thin features were rebuilt from geometry the 0.01 mm coordinate grid had turned into a staircase. A caddy now lays the same divider length at 0° and 45°, to within 1 %.
• A thin feature survives a wide nozzle — anything under the minimum bead width was dropped outright, so a 0.6 mm nozzle printed a caddy as a solid block. It now prints at the minimum width, down to half of it.
• Thin features print end to end, and a bead no longer breaks into a file of millimetre dabs where the material it follows briefly narrows.
• A tapering bead keeps its taper over a bridge or overhang — splitting walls there used to discard per-vertex widths for the whole layer.
• No more strands between thin ribs — a cavity now counts as air, and every hop between ribs dives back through the body rather than reaching for the free tip. On a 25-slot caddy, unretracted travel across open air falls from 5.5 m to 0.8 m.

Overhangs and layers

• Overhang detection measures material, not centrelines — near-vertical funnels, chamfered lips and flaring hulls were getting bridge speed and bridge cooling for surfaces landing on solid plastic. Steep-but-touching walls are still slowed and cooled, but keep wall flow and stay one continuous loop.
• Overhangs are classified by geometry, not by rounding — a uniform 0.34 mm ledge used to come back with four alternating verdicts around one circle.
• Small layers no longer crawl to a blob — the minimum-layer-time slowdown scaled against the general print speed, so bridges, overhang bands and ironing fell straight through the min_print_speed floor. The floor now applies to the speed actually emitted, and nothing dwells to make up a shortfall.
• Supports work on sloped overhangs — the threshold angle was inert because overhang classification had already retagged the walls the support stage measures. A 60° cone goes from nothing to full support; a 30° one is still left alone.
• Support islands print whole — the segment closing each perimeter loop was never extruded, leaving every island open on one side. The same fix closes a wall loop that overhangs along its entire length.
• Support prints as loops, not dabs, and no longer over-extrudes — it is charged at its flow spacing like every other fill role, about 12 % less than a full nozzle-width bead.
• Rafts and skirts account for supports, which used to start in mid-air just above the plate.
• Supports are switched off in spiral (vase) mode, where nothing could reach them anyway.

Workplates and the app

• Switching tabs actually switches plates in every runtime, and a plate comes back with each model's position, rotation, scale and support paint intact.
• Your plates survive closing the app — models are kept on the device beside the plate. Room for them is bounded, oldest-unopened first.
• + starts a plate instead of throwing one away, and a renamed tab keeps its name everywhere. Renaming is a double-click; tabs work from the keyboard.
• Switching back to a plate no longer re-downloads its models, and reloading always gets the current build.
• Plates holding several models slice correctly everywhere — the desktop app sliced every object out of the first model, and the browser slicer refused outright.
• The app notices when the engine goes away — a heartbeat spots a dead connection within seconds and reconnects; edits made while it is down report the problem instead of vanishing.
• Tapping a model on a tablet selects it — a parked invisible gizmo hit area swallowed taps, and a mouse-sized 4 px tolerance discarded a fingertip's wander as a drag. Tolerance is now judged per pointer.
• The slice progress bar tracks real work — four phases carried no weight at all and froze the bar while they ran.
• "Use filament colour" honours the colour you set, in the viewport and in the embedded thumbnail.
• Undo while typing undoes your typing, not the last thing you did to the plate.
• Notifications no longer pile up, dialogs fit on iPhone and iPad, and a finished slice reports its own layer count.
• Closing a workplate tab works.

Contributors

Thanks to @max-scopp, who shipped this release end to end — supports, walls, workplate tabs and the printer wizard all landed in this cycle.

[0.4.0] - 2026-08-31

The biggest release so far — 181 files and about 15,000 new lines — and it pulls in two directions at once. Print quality gains the three settings that were missing or only pretended to work: ironing, dimensional compensation and a real first layer height. And the app itself stops being desktop-only: an iPad or a phone now gets a layout, gestures and controls built for it, on a home screen that draws in a fraction of the time.

Highlights

• Ironing, dimensional compensation and a real first layer height — the finishing controls a print actually needs. Ironing re-melts top surfaces flat, XY/hole compensation corrects a machine that prints over- or under-sized, and the bottom layer is finally sliced and extruded at the thickness the profile asks for.
• Elephant-foot compensation that keeps thin detail — the flare at the base of a print is removed without erasing the first layer's fine geometry. Unlike a plain shrink, the correction is limited by how thin the model is at each point, so embossed text, logo strokes and thin ribs survive where a uniform 0.3 mm offset would delete every feature under 0.6 mm.
• A slicer that fits a tablet and a phone — an iPad keeps the desktop layout but folds panels away from the plate, tap, long-press and drag work with a finger or a Pencil, and below 640px the whole interface rearranges into a bottom tab bar, a settings drawer and a slice sheet. Previously a 390px screen gave the 3D view about 50px of width.
• A home screen that appears immediately — 691 kB to first draw, down from 1.58 MB, with the slicing engine, the 3D viewer and the code editor loaded only when you reach for them. Blocked main-thread time on arrival falls from about 2 s to under 30 ms.

Added

• Support structures — overhangs steeper than the threshold angle (45° by default) now get real support geometry instead of a "not implemented" warning. Two styles: normal grid columns and tree branches that converge as they descend. Dense interface layers, an XY clearance and a Z air gap keep the contact clean enough to snap off.
• Only from build plate — restricts support to columns that can reach the bed through open space, so nothing lands on the print. Overhangs with no route down are left unsupported on purpose. Off by default; on a shelf overhanging a wider base it removed every millimetre resting on the model while keeping the support beyond it.

Print quality

• Ironing — the top-surface smoothing toggle now does something. Previously it could be switched on in the profile wizard, was documented as working, and logged "not yet implemented" at slice time. A near-dry pass re-melts finished top surfaces flat, with its own type, flow (10 %), spacing (0.1 mm), speed and angle, and its own colour in the preview.
• Dimensional compensation — correct a machine that prints consistently over- or under-sized. XY size compensation offsets every contour; hole compensation adjusts holes on their own, so a tight press-fit can be freed without moving the outside of the part. Both default to off.
• Elephant-foot compensation — corrects the flare the bed's squish leaves at the base of a print. Unlike a plain shrink it is limited by how thin the geometry is at each point, so embossed text, logo strokes and thin ribs on the first layer keep their width instead of being erased. It also holds back where the model itself flares steeply outward, and switches itself off on a raft. Off by default; 0.1–0.2 mm suits most machines.
• First layer height — now affects the print instead of only the file header. The bottom layer is sliced and extruded at its own thickness, so a profile asking for 0.24 mm no longer silently prints 0.2 mm. Skirt and brim follow it; a raft suppresses it.

Tablets, phones and touch

• Tablet layout — an iPad keeps the full desktop arrangement but stops leaving panels open over the plate: the G-code inspector and the object list both start folded, and the print-settings tab moved out of the middle of the screen, where the model is. Opening the settings drawer no longer dims the plate behind it — you are peeking at the settings, not leaving the model. Applies to any window under 1024px, so Split View and a docked desktop window get it too.
• Phone layout — the whole UI rearranges itself below 640px instead of overflowing. Navigation moves to a bottom tab bar, print settings become a drawer with a pull tab on the left edge, and Slice sits in a full-width sheet along the bottom with the G-code inspector scrolling inside it. Settings sections become a scrollable chip strip and the printer/filament/profile editors stack instead of splitting into two columns.
• Finger-sized controls on touch screens — buttons, dropdowns, legend chips and the layer slider are now sized for a fingertip on every touch device rather than only on phones. The layer slider's grip went from 18px to 26px; scrubbing through layers on a tablet was the worst of it.
• A context menu on the plate — right-click a model, or press and hold it on a touch screen, for Duplicate, Drop to floor, Centre on bed and Remove, acting on the whole selection when you have one. Holding empty bed offers select all, clear, place objects and reset view.
• Multi-select for touch and pen — a tool-cluster toggle that makes each tap add or remove an object, standing in for the ⌘/Ctrl a tablet has no key for. It appears once there are two objects to choose between, and turns itself off when it can no longer be reached.
• Drag a selected model across the bed — with a finger or a pen, select a model and then drag it. Dragging anywhere else still orbits, so nothing moves unless you picked it first. The move handles are also drawn larger on touch, so a fingertip can pick one axis instead of all three.
• Fold the G-code legend out of the way — the inspector now has a header you can tap to collapse it to a single row, keeping the layer counter and the Slice button in place. Unfolded it sizes itself to the room actually available, so on an iPad the whole legend and both sliders are visible without scrolling. It starts folded on tablets, phones and narrow windows, open on a large screen, and remembers whichever you choose.

Loading and startup

• A loading screen on first open — the logo now appears immediately with a progress bar beneath it, instead of a blank page while the app downloads. A tiny embedded copy shows straight away and sharpens once the full artwork arrives, and the bar tracks the real download rather than guessing.
• Visible page loading — switching between Home, Slice and Settings shows a thin progress line and marks the destination in the navigation rail whenever the wait is long enough to notice. Anything under 120 ms stays silent, and the app quietly pre-fetches the other areas once it has finished starting up.
• Reload prompt for stale tabs — if a page can no longer be loaded because the app was redeployed under an open tab, the existing update banner now offers a reload instead of the click doing nothing.

Platform

• Keep the app on an iPhone or iPad without a Mac attached — pnpm run ios:install builds the release app, signs it with a free Apple ID and installs it on a connected device, so it keeps working after the dev server stops. No paid Apple Developer Program: the trade is that a free signature lasts seven days, and re-running with --renew resets the clock without touching your models, profiles or settings.
• Preset catalog picking got faster and more honest — the picker loads a page at a time instead of walking the whole category, fetches the complete preset when you import it (so its slicing parameters really arrive), and shows a busy state on the entry you picked while it does.
• GitHub links in the title bar and catalog picker — a direct route to the project, and to the source of any catalog preset.

Changed

Speed and size

• Faster startup — the app now downloads 691 kB before it can draw, down from 1.58 MB. The 3D viewer, the settings workspace and the code editor are fetched when you actually open them, not before the home screen appears.
• The home screen appears without waiting for the slicing engine — the ~750 kB WebAssembly engine and its worker used to load before the first screen could draw, even though nothing there needs them. They now load once the browser is idle, or the moment you open a model, whichever comes first. Blocked main-thread time on arrival falls from about 2 s to under 30 ms, and the page weighs 536 kB less.
• Smaller install and deploy — the bundled code editor no longer ships ~90 programming-language grammars and four language servers it never used. Total deployed JavaScript falls from 17.7 MB to 8.4 MB.
• Settings pages open without loading the code editor — the G-code editors on the printer and filament pages sit well below the fold, but still cost ~4 MB the moment the page opened. They now load when you scroll to them.
• The in-app logo is 74% smaller — 52 kB of PNG became 14 kB of WebP.

Interface

• Touch targets and form rows on phones — controls grow from 34px to 40px, labelled rows stack so a dropdown gets the full width, toasts move to the top of the screen (the bottom now belongs to the slice sheet), and the object list folds to a chip that still flags a part that cannot print.
• The object list remembers whether you folded it — it starts folded on a tablet or a narrow window, and unfolding it now sticks instead of resetting on the next visit.
• Two controls are hidden on phones — the viewport cube, which needs a drag it cannot receive, and the projection toggle and operation-pipeline inspector, which do not fit alongside the tools that get a model sliced. All three return on any wider screen.
• You can pinch to zoom the interface again — zoom was disabled across the whole page to keep gestures away from the 3D view. Only the 3D view holds onto them now, so settings, prose and small print can be magnified everywhere else.
• Muted text is legible — the quietest text tone sat below the contrast minimum in both themes, and well below it in light mode. It has been darkened (light) and lightened (dark) enough to pass on every surface it appears on.
• "Running in your browser" appears when you open a model, not the instant the page loads. Same message, but it now arrives when you have something to slice — and it is no longer the first thing a new visitor meets.

Development

• The dev stack starts on a seeded pair of random ports, so a second worktree, a colleague on the same machine or a parallel agent session never collides with yours.
• The documentation site now wears the app's own design language, built from the same theme tokens the product uses, so the two cannot drift apart.

Fixed

Touch and gestures

• Tapping a model on a tablet now selects it — two separate faults made touch and Pencil selection fail. An invisible transform-gizmo hit area sat parked at the centre of the bed whenever nothing was selected, and swallowed any tap that landed on it; that check runs only for touch and pen, so a mouse never saw it. Selection was also judged by a mouse-sized 4px tolerance, and a fingertip is a ~10mm disc whose reported centre wanders as the skin flattens, so most real taps were discarded as drags. Taps are now judged per pointer — 4px for a mouse, 9 for a pen, 16 for a finger — and a hidden gizmo no longer intercepts anything.
• Pinching to zoom no longer spins the model on a touchscreen — rotation is measured as an angle, so its noise floor grows as your fingers close; a measured pinch-in sprayed ~16° of unwanted roll. Twist now has to be a sustained, deliberate turn, and once you have clearly started pinching the view is locked against rolling for the rest of the gesture.
• Slow pinches now zoom — a gentle pinch moves well under a pixel per event on a 120 Hz iPad, and every one of those was discarded rather than banked, so the camera simply refused to move. Small movements now accumulate.
• A palm can no longer hijack a two-finger gesture — a hand settling while two fingers were already pinching was let through, and took over the gesture the moment a real finger lifted.
• Losing a finger no longer freezes the camera — a touch released over the toolbar, or the app being backgrounded mid-pinch, could strand the viewport with navigation disabled until the page was reloaded.

Plates and slicing

• Plates holding several models now slice correctly everywhere — a workplate is a build plate, not a file, but only the hosted slicer treated it that way. The desktop app sliced every object out of the first model, so a second one came out as a copy of the first; the in-browser slicer refused outright with "Missing mesh bytes". Each object now resolves to the file it was actually loaded from, in every runtime.
• The desktop app now prints the plate you arranged, not the file you opened — models were sliced exactly as their source file defined them, ignoring every move, rotation and drop-to-bed. A multi-part 3MF came out with its parts still stacked as the authoring tool assembled them, and duplicates or extra parts were dropped entirely.

Interface

• The "Print settings" tab no longer flickers when you hover it — pointing at the tab used to open the drawer, which hid the tab, which closed the drawer, in a loop. Resting at the very edge of the screen still peeks at the panel; the tab itself now only responds to a click.
• Dialogs no longer collapse in Safari — a dialog with a body ("Running in your browser", "What's New", the operation pipeline) drew as a title with the buttons jammed underneath and its content squashed to one clipped line. It now opens at its full height and scrolls when taller than the screen. Affected iPad, iPhone and the macOS app; the in-browser slicer worst of all, since its welcome notice is a dialog.

Next up

Two big ones are being worked on right now:

• Support structures — the last major gap in the pipeline. Overhangs that need holding up will finally get held up.
• Importing your existing profiles — bring the printer, filament and process profiles you have already tuned in another slicer straight into this one, instead of rebuilding them by hand.

Contributors

Thanks to @max-scopp for shipping this release.

[0.3.0]

The preset catalog goes live. "Pick it from the catalog" in the printer and filament wizards now browses the real Cold Crabby Preset Cloud instead of an empty placeholder, so a new profile can start from a genuine vendor preset. Add touch-friendly undo/redo in the 3D view and a round of Windows desktop polish.

Highlights

• Live preset catalog — the printer and filament wizards now search the Cold Crabby Preset Cloud for vendor presets and pre-fill a new profile from your pick. Search is ranked server-side across the whole catalog, and if the cloud is unreachable the app falls back to its built-in defaults and keeps working offline.
• Undo / redo in the 3D view — history buttons on the plate toolbar for touch devices where the ⌘/Ctrl+Z shortcut can't be reached.

Added

• Preset catalog picker — browse and search real vendor presets when creating a printer or filament profile; a pick pre-fills the profile's identity fields, tagged with a link back to its catalog source.
• Undo / redo buttons in the 3D view — forward and backward history buttons on the plate toolbar. Shown automatically on keyboard-less tablets and phones; force them on or off in Settings → General → Controls. Auto by default.

Changed

• Live accent tracking is event-driven — the desktop app now updates its accent tint the moment you change it in the OS (Windows registry change notifications; macOS distributed notifications) rather than catching up on a 2-second poll.

Fixed

• G-code editors render properly in the browser build — the printer and filament G-code boxes could show up as a plain, unstyled text field instead of the syntax-highlighting editor, most often on the in-browser (WASM) version. The editor now waits for its own styles to load before it appears, so it comes up fully formed every time.
• Undo no longer wipes the plate after navigating — dip into Settings and back, or use the browser's back button, and your objects keep their positions and undo history instead of being deleted by the next undo. History now resets only when the workplate is genuinely replaced.
• The "re-slice" hint no longer clears itself — moving an object or changing a setting while a slice is running used to be silently absorbed into the preview once it finished, so the "Scene changed — re-slice" hint disappeared even though the on-screen G-code predated your edit. The comparison baseline is now captured the moment you press Slice, so a mid-slice change correctly keeps the hint lit until you re-slice.
• No more flashing console on Windows — the desktop app used to re-read the OS accent colour every couple of seconds by shelling out, which popped a brief cmd window on Windows on every check. It now reads the accent directly and waits for the OS to signal a change instead of polling, so the flickering after login is gone and macOS stops re-checking on a timer too.
• No more launch hang on Windows — the desktop app used to open a blank, unresponsive window for a moment on Windows before it became usable. Its window now stays hidden until the interface has actually drawn, so the app appears fully rendered and ready the instant you see it.

Contributors

Thanks to @max-scopp for shipping this release.

[0.2.0] - 2026-08-30

The build plate grows up. What used to be one model on a plate is now a real build plate — add as many objects as you like, cancel a failed one mid-print, or print them one at a time — and every infill pattern finally deposits the exact density you ask for at any line width.

Highlights

• Multi-object build plates — place several models on one plate, manage them in a new Objects panel, cancel a single failed part from Mainsail/Fluidd, or print parts sequentially front-to-back. Multi-part 3MFs land as separate, named objects instead of one fused blob.
• Infill that hits its density — line spacing and per-line flow now come from the real extrusion width, not a hardcoded 0.4 mm. Grid stopped printing double, honeycomb tiles and stacks like it should, and a 0.6 mm nozzle asked for 20 % no longer prints ~13 %.

Added

Infill & surfaces

• Advanced infill options — infill anchors (weld sparse lines to the wall and merge broken dashes into one continuous move — the biggest quality win here), sparse-infill layer combining (print shared infill once at a stacked height), internal solid layers, separate top/bottom/internal surface patterns (including monotonic for a cleaner top finish), and a bridging-angle override. All off, or matching the previous behaviour, by default.
• Five more infill patterns — aligned-rectilinear, triangles, tri-hexagon, cubic and concentric. OrcaSlicer's pattern names are accepted as-is, so imported profiles map without a translation table.
• Spiral (vase) mode — spiral_vase (CLI --spiral-vase) prints a single continuous outer wall whose Z ramps smoothly over each layer, for a seamless single-wall vase with no Z-seam. Off by default.

Multi-object build plates

• Cancel one object mid-print, or print objects one at a time — the plate now tracks which part every extrusion belongs to. Exclude object wraps each part in firmware markers (Klipper EXCLUDE_OBJECT_*, Marlin / RepRapFirmware M486) so a failed part can be cancelled from Mainsail, Fluidd or OctoPrint while the rest of the plate carries on. Sequential printing (Print order → by object) finishes each part front-to-back, lifting clear of everything already on the bed, with clearance checks reported as warnings and optional between-object G-code. Both off by default; with both off the plate slices exactly as before.
• Multiple objects per workplate — a plate is now a build plate, not a single file. An Add model button and a multi-select picker place more models without replacing what's there, a new Objects panel lists and manages them (flagging anything out of bounds or overlapping), and reopening a saved plate restores every object. Multi-part 3MF files now land as separate, named objects instead of one fused blob.
• One placement command — a single Place objects tool replaces the rival "auto-orient" and "arrange all" buttons that undid each other's work. It sits with move / rotate / scale and opens a card for the two things worth varying (auto-orient and gap). The same settings apply when you drop a model in.
• Preferred print orientation, per printer — set a diagonal angle (e.g. 45° for CoreXY) applied to every auto-oriented part after it's laid on its best face. Defaults to 0° (untouched).
• Multi-object CLI slicing — slice -i part_a.stl -i part_b.stl builds one plate. A new --arrange flag (with --arrange-spacing and --arrange-auto-orient) packs it without overlap, and the transform flags apply to every loaded model.

Printer & firmware output

• Chamber temperature management — the filament asks for a chamber temperature (with a hotter first-layer soak) and the printer says whether it can deliver it; only when both agree are directives emitted, with a safe soak sequence and Klipper's native commands. A start G-code that already heats the chamber keeps ownership.
• Z offset — a per-printer z_offset_mm (Settings → Printers → Hardware) added to every Z coordinate written to the G-code, so it works on any firmware with no macro to maintain. Same meaning as in PrusaSlicer and OrcaSlicer.
• Dynamic overhang speed & cooling — perimeter segments are graded by how much hangs over unsupported air, and each degree prints at its own speed with extra part-cooling. On by default.
• Advanced retraction modes — firmware retraction (G10/G11), relative extruder distances, minimum-travel-before-retract, restart-extra prime, retract-on-layer-change, and wipe-while-retracting. All default to the previous behaviour.
• Perimeter routing & ordering options — external_perimeters_first (outer wall now printed last by default, matching PrusaSlicer/Orca/Cura), extra_perimeters, thin_walls (classic generator), and ensure_vertical_shell_thickness and avoid_crossing_perimeters. Defaults preserve existing behaviour except the inner-first ordering.
• Volumetric-flow limiter — max_volumetric_speed (mm³/s) caps the feedrate so the hotend is never asked to melt faster than it can, per-segment for variable-width beads. Defaults to 0 (unlimited).
• Geometry-aware acceleration — outer_wall_acceleration and bridge_acceleration add role-specific limits on top of layer-type acceleration (lower outer-wall for less ringing, low bridge for steady flow). Default 0.
• Layer-type acceleration control — acceleration, first_layer_acceleration and top_surface_acceleration emit a firmware acceleration command when the target changes. Default 0.
• Pressure / linear advance output — a non-zero pressure-advance value is emitted once after the start script in the correct firmware form (Klipper SET_PRESSURE_ADVANCE, Marlin M900 K). 0 disables it.
• G-code metadata header — every program opens with a flavor-specific metadata block: slicer version and timestamp, model name, layer count, height, filament usage, time estimate and bounding box. A new filament_density_g_cm3 drives the weight.

Models & profiles

• Automatic mesh repair on import — holes are capped, cracked vertices welded, inside-out triangles turned right-side-out, and zero-area or duplicate triangles dropped. The UI raises a toast, the CLI logs a warning, and a new mesh-check command prints a full report without slicing. Clean models are never touched; pass --no-mesh-repair to slice the raw geometry.
• Export your profile library — Settings → General downloads every printer, filament, print profile and label as TOML (a ZIP bundle, or a single profiles.toml the engine reads directly). Printer API keys are stripped, so the export is safe to share.
• Settings tell you when they depend on something else — a chamber temperature set for a printer with no chamber heater now says plainly it won't take effect and links to the fix. The CLI prints these warnings too.

App, platform & tooling

• Release notes inside the app — Settings → What's New lists every release, newest first, with the version you're running highlighted. The post-upgrade dialog shows that same list.
• iPadOS / iOS target — the Tauri shell now builds and runs on iPad with the full slicing engine on-device. The pnpm run ios:* scripts drive the toolchain, Xcode project generation, and a live-reload simulator build.
• Slice diagnostics & bed-type tracking — a bed_type setting is recorded in the header, and the slice CLI reports model height, filament usage and the estimated print time.
• Live versioning — every build reports its true version, derived from git tags. Development builds report development.
• Embedded changelog — bundled into every target; the UI shows a "What's New" dialog the first time it runs after an upgrade.
• Releases pipeline — tagging vX.Y.Z builds all targets and publishes a release whose notes are taken from this file.
• Commit revision in build info — every build records the exact short commit hash, shown in Settings → General and reported by the CLI info command.

Changed

Infill accuracy & patterns

• Infill density is now accurate at every line width — line spacing and the flow charged for each line both come from the real extrusion width, not a hardcoded 0.4 mm reference. A 0.6 mm nozzle asked for 20 % used to print ~13 %.
• Grid infill no longer prints double — it laid two full-density passes instead of two half-density ones. Honeycomb cells and the gyroid period are on the libslic3r relations now too, and all scale with the line width.
• Honeycomb is a real hexagonal tiling — continuous zig-zag walls drawn once, instead of stamped hexagons with every shared wall drawn twice.
• Honeycomb cells stack again — it (and triangles, tri-hexagon, cubic) was rotated 90° every other layer and keyed to the region's bounding box, so walls landed on the layer below's voids. Consecutive Voron-cube layers now share 79 % of their infill geometry, up from 2 %.
• TPMS-D actually prints now — its segments are chained into continuous curves and the period recalibrated, so it deposits the full requested density instead of about a seventh.
• Top surfaces default to monotonic line, bottoms to monotonic — a cleaner, direction-consistent finish that also stopped 106 mm² of top-surface material printing over the inner wall on a Voron cube.

Docs & dependencies

• The documentation now leads with the product, not the architecture — a proper guide to using Cold Crabby plus a teams track for self-hosting and configuration, with the engineering docs slimmed to a map. A banner notes the docs are early and their structure may still change.
• Dependency maintenance — cleared the Dependabot backlog: the Angular front-end moves to the 22.x line on TypeScript 6.0, the Rust engine to sea-orm 2.0 and reqwest 0.13, plus the grouped npm bumps. No behavioural change to sliced output.

Fixed

Print quality

• Your filament's cooling settings are now actually used — Fan Speed, Bridge Fan Speed, First Layer Fan Speed and Fan Off For First Layers were shown and saved but ignored by the generator, so the part-cooling fan ran during the first layer for every material, quietly costing bed adhesion. Fan Speed is now the cooling ceiling, and the bridge and overhang boosts are held back on the layers where cooling is off.
• Isolated infill specks in narrow wedges — a connected infill region too small to hold more than one dash (2 mm² at a 0.4 mm nozzle) is now skipped. It's an area rule, so a genuinely thin cavity that deserves a lattice keeps every line.
• Generator-specific wall options are now hidden for the generator that ignores them — thin_walls / wall_distribution_count (classic) and gap_fill_min_length_mm (Arachne). This also stopped thin_walls from silently deleting Arachne's thin features — turning it off had wiped ~50 slot fins on a filament card caddy. Arachne now always prints thin features.
• Top-surface "squiggles" where solid fill grazes a wall — a surface meeting the wall band at a shallow angle was filled with a dense micro-serpentine of sub-millimetre stubs. Solid surface regions narrower than one extrusion width are now dropped before filling, while thicker geometry keeps its exact shape and sharp corners.
• Arachne "splat" gap-fill and gap fill under top surfaces — isolated sub-millimetre gap-fill beads (≈270 on a 3DBenchy) that cost a full retract/travel/un-retract each are dropped, and a redundant bead running under a thin solid strip is pruned with the surface filling the strip in its place.
• Tiny sparse-infill "splat" dashes — solid_regions is now grown by one bead before being subtracted from the infill area (killing the crescent slivers the scanline shattered into dashes), and min_infill_extrusion_mm also filters sparse infill. Together with the gap-fill fixes this cut isolated sub-0.8 mm extrusions on a 3DBenchy by ~76 %.

Interface & import

• The documentation site failed to build — a line of prose wrapped an inline code span across a line break, leaking its placeholders out as raw, unclosed HTML.
• The transform panel was blank whenever more than one object was selected — it now edits the whole selection: Position shifts every part by the same amount (keeping your layout), while Rotation, Scale and Size apply per part about each one's own centre.
• The arrange gap defaulted to 0 mm on a fresh install — an unset preference read back as 0 rather than "unset". It now starts at 4 mm.
• iPad Apple Pencil + two-finger navigation "spazzing" — the viewport's pointer arbiter now classifies a whole gesture group at once, so a two-finger pan/pinch is never split into a stray single-finger camera rotate.
• 3MF models loaded at the wrong scale — the importer ignored the <model unit="…"> declaration and read every coordinate as millimeters. All six spec units are now normalized on import.
• Viewport-cube ortho snap popped back to perspective on pan/zoom — only a genuine rotate now breaks the flattened, dimension-true view; panning and zooming keep it, so you can inspect a snapped view up close.

Contributors

Thanks to @max-scopp, who built everything in this release. Onward to 0.2.0.

[0.1.0] - 2026-08-23

Added

• Initial slicer engine: STL/OBJ/3MF loading, mesh slicing, Arachne variable-width wall generation, top/bottom surface detection, and infill.
• Unified scene engine (single source of truth for object placement) shared by the CLI, WebSocket server, and WASM UI.
• Angular UI with a Three.js viewport and G-code preview, plus a Tauri desktop shell.
• Command-line interface with slice, info, and schema-generation commands.