Porting and attribution

glitter's source falls into four buckets. NOTICE (repo root) is the authoritative, maintained ledger; this page explains what the buckets mean and summarizes the deviations; if the two ever disagree, NOTICE wins.

Bucket 1: ported from Replicant

Mechanical rename port (replicant.* → glitter.*, including the :replicant/* keyword namespace) via sed -E 's/\breplicant\b/glitter/g', from Replicant commit 379bb3c1ad4d5d3002c57e67ab647d12f3c2d322 (2026-07-25), Copyright 2023-2025 Christian Johansen, MIT License.

Ported files: glitter.protocols, glitter.hiccup, glitter.hiccup-headers, glitter.console-logger, glitter.errors, glitter.assert, glitter.vdom, glitter.asserts, glitter.core, glitter.alias.

glitter.core (the diff/reconcile algorithm) is the largest and most important of these, and carries three deliberate deviations from a pure mechanical port:

build-event-map's :clj branch reads (:glitter/node e) instead of hardcoding nil. Replicant's #?(:cljs (.-target e) :clj nil) reflects that its :clj branch was never exercised by a live DOM (Replicant targets ClojureScript/the browser), but glitter's events are live, so the acting element has to travel through somehow. glitter.gtk supplies it as :glitter/node on the event map it hands to the dispatched handler.
set-dispatch! is new code, not a port. It doesn't exist in replicant.core at all; only *dispatch*, the dynamic var it reads. The function lives in replicant.dom (browser-specific, never ported; see Bucket 3), so glitter added its own one-liner mirroring that original: (defn set-dispatch! [f] (alter-var-root #'*dispatch* (constantly f))).
update-attr/set-attributes route on (some? v) instead of truthiness. DOM attributes have a natural "absent" state that coincides with false for most practical purposes (an if-let-style truthiness check works because DOM callers rarely need to distinguish "explicitly false" from "not set"). GTK properties don't share that: a checkbutton's :active false or a widget's :sensitive false is a real, meaningful boolean value that must reach the widget, not get silently treated as "attribute absent, remove it." Verified live against real GTK state during the project's final whole-branch review.

Bucket 2: forked from glimmer

glimmer is authored by Dmitri Sotnikov (Yogthos) under the jolt-lang organization: a different author from glitter's, verified from git history on upstream/main (29 commits, 25 as Yogthos and 4 as Dmitri Sotnikov, zero by anyone else). Upstream ships no LICENSE file, so no grant has been made; this bucket records provenance, not a claimed permission. See NOTICE's ## glimmer section for the authoritative statement and its full reasoning:

glitter.ffi: forked from glimmer.ffi, plus 223 new bindings added across the widget rounds. NOTICE's src/glitter/ffi.clj entry is the authoritative, exhaustive list; it is deliberately not repeated here, because this page's own rule is that NOTICE wins when the two disagree, and a hand-maintained second copy is exactly how they come to disagree.

What the bindings are for, in roughly the order they arrived:

The original port: signal disconnect, box insert-after, label read-back, prev-sibling lookup.
:scale, :class: GtkRange/GtkScale value and range, CSS-class add/remove/query.
Display-only widgets: :spinner, :progress-bar, :image, later :picture and :inscription.
Interaction widgets: :toggle-button, :level-bar, :link-button, :switch.
Container strategies: :revealer, :center-box, :list-box, :paned, :overlay, :flow-box, :header-bar, :action-bar, :grid, :stack.
GtkEditable family: :password-entry, :search-entry, :editable-label.
Value / selection widgets: :spin-button, :scale-button, :notebook, :drop-down, :calendar (including refcounted GDateTime).
Popup surfaces: :menu-button, :popover, :window-handle.
The ctor/apply audit: GtkAdjustment accessors plus gtk-checkbutton-set-label, added to fix four previously-shipped bugs.

One binding arrived outside any widget round: gtk-widget-get-sensitive, added while verifying examples/glitter/crud.clj. Every prior use of :sensitive only ever set it; that was the first live check of its own read-back.

glitter.widget: forked from glimmer.widget. What was added, and the four places its behaviour deliberately diverges from glimmer's.

Added, alongside the shared helpers insert-child-after!, signal-name, signal-value-fn, suppressing?:

:scale: the first-party demonstration of the value-bearing custom-signal path.
:spinner, :progress-bar, :image, :level-bar, display-only: no signal wiring, driven entirely by re-applied props.
:toggle-button, :link-button: both reuse an existing signals entry verbatim.
:switch: the widget that forced glitter.gtk/set-event-handler itself to generalize.
:revealer: display-only, and a free single-child-container reuse.
:center-box, a genuinely new container strategy: three fixed named slots, not an ordered list.
:spin-button: forced signal-value to be keyed by tag as well as signal name.
:list-box: a third callable shape, plus two more real bugs found and fixed.

Four behavioural deviations from glimmer:

replace-child!'s :box branch captures the old child's previous sibling via gtk_widget_get_prev_sibling and re-inserts with gtk_box_insert_child_after, where glimmer used gtk_box_remove + gtk_box_append. append always lands at the end of the box, silently relocating any non-final child.
signal-value is keyed by [tag gtk-signal-name], not by bare signal name: :spin-button and :scale emit the identical "value-changed" signal but need different getters.
insert-child-after!/reorder-child! are no longer :box-only no-ops. :list-box needed both genuinely implemented; :center-box gets insert-child-after!, but its reorder-child! stays a structural no-op (three fixed slots have no ordering to change).
list-box-remove-child!/list-box-replace-child!/ list-box-reorder-child! suppress on the list-box widget around gtk_list_box_remove; removing the currently-selected row fires a real, synchronous "row-selected(NULL)" signal that would otherwise reach app dispatch.

Round 7 adds password-entry-spec/:password-entry + search-entry-spec/:search-entry (both reuse :entry's GtkEditable-delegate "changed" signal name, but each still needed its own signal-value entry under [tag "changed"]; reusing :entry's registration doesn't work once signal-value is keyed by tag; :search-entry also gets its own new :on-search-changed; see gtk-widget-layer.md), set-expander-expanded!/expander-spec/:expander (single-child container, no dedicated signal; :on-expanded watches "notify::expanded" instead), and set-paned-position!/paned-spec/ :paned + paned-append-child!/paned-slot-setter/ paned-remove-child!/paned-replace-child!/paned-insert-after! (a second new named-slot container strategy; 2 slots this time; :on-position-changed watches "notify::position"; both :expander's and :paned's notify::* signals reuse :list-box's generalized 3-arg-void set-event-handler shape for free, and :paned inherits :center-box's structural v1 gap with a verified-DIFFERENT failure shape; see gtk-widget-layer.md).

Round 8 adds aspect-frame-spec/:aspect-frame (single-child container, same strategy as :frame/:scrolled/:revealer/ :expander; quick win, see gtk-widget-layer.md), calendar-date=/set-calendar-date!/calendar-spec/:calendar + the new :on-day-selected signal (this project's first GDateTime- refcounted value type; same anchor as :aspect-frame above), overlay-spec/:overlay + overlay-append-child!/ overlay-remove-child!/overlay-replace-child!/overlay-insert-after! (a THIRD new container strategy; one queryable main slot plus an unbounded, unenumerable overlay set; see gtk-widget-layer.md), and flow-box-spec/:flow-box + flow-box-child-of/ flow-box-index-after/flow-box-insert-after!/flow-box-replace-child!/ flow-box-reorder-child! + the new :on-child-activated signal (a :list-box sibling verified to NOT share gtk_list_box_remove's gotcha; same anchor as :overlay above).

Round 9 adds editable-label-spec/:editable-label + set-editable-label-editing! (a THIRD GtkEditable-delegate reuse, after :password-entry/:search-entry; repeated the exact signal-value-miss near-miss from round 7 despite a comment saying it would be avoided, caught only by live probe testing; investigating it surfaced a general GtkEditable finding, not specific to this widget; see gtk-widget-layer.md), picture-spec/:picture (display-only, no signal; same anchor as :editable-label above), notebook-spec/:notebook + notebook-append-child!/notebook-remove-child!/ notebook-replace-child!/notebook-index-after/ notebook-insert-after!/notebook-reorder-child! + set-notebook-current-page! + the new :on-switch-page signal (a SIXTH generalized set-event-handler callable shape, the first that reads its own raw signal argument instead of a getter, and a verified real mount-time auto-dispatch; see gtk-widget-layer.md), and scale-button-spec/:scale-button + set-scale-button-value! (a THIRD widget sharing :scale's/:spin-button's "value-changed" signal name, the first case needing a TAG-aware, not just signal- name-keyed, set-event-handler dispatch; same anchor as :notebook above).

Round 10 adds inscription-spec/:inscription and search-bar-spec/:search-bar (both entirely display/props-driven, no signal, no glitter.gtk changes needed at all; see gtk-widget-layer.md), header-bar-spec/:header-bar + action-bar-spec/:action-bar + header-bar-append-child!/header-bar-remove-child!/ header-bar-replace-child!/header-bar-insert-after! + action-bar-append-child!/action-bar-remove-child!/ action-bar-replace-child!/action-bar-insert-after! (a genuinely new HYBRID container shape; one named title/center-widget slot plus an ORDERED pack-start list; that surfaced two real findings: both widgets' pack_end silently reverses hiccup order, confirmed independently for each rather than assumed to carry over, so v1 only wires pack_start; and toggling :show-title-buttons prepends GTK's own native window-controls widget into the SAME pack-start region; see gtk-widget-layer.md), and menu-button-spec/:menu-button + popover-spec/:popover + set-popover-visible! + the new :on-closed signal entry (the FIRST popup surface in this project and the first hiccup relationship that isn't a normal append-child!-managed tree child; :menu-button's ONE hiccup child, if present, is attached via gtk_menu_button_set_popover rather than any container-management case branch reused from an existing widget; both :on-activate and :on-closed turned out to be free reuses of the default 2-arg-void callable shape, needing zero glitter.gtk changes; see gtk-widget-layer.md).

Round 11 adds a ctor/apply audit that found and fixed four real, previously-shipped bugs; checkbutton-spec's never-applied :label, and scale-spec/spin-button-spec/scale-button-spec's :min/:max/:step silently clobbering each other across single-key re-renders; see gtk-widget-layer.md; window-handle-spec/:window-handle (single-child, no signal; quick win that also caught a missing-case-branch bug in this round's own new code; see gtk-widget-layer.md); set-stack-visible-child-name!/stack-spec/:stack + the new :on-visible-child-changed signal entry (a THIRD mount-time-auto- dispatch instance, plus a real :apply-timing gap fixed at the warning level only; see gtk-widget-layer.md); set-drop-down-selected!/drop-down-build-model!/drop-down-spec/ :drop-down + the new :on-selected-changed signal entry (the first "choose from options" widget, built on an incrementally-constructed GtkStringList; see gtk-widget-layer.md); and grid-attach!/stack-append-child!/grid-spec/:grid (the first container whose child placement is driven entirely by the child's own hiccup props, via the new :glitter/structural-props mechanism; see gtk-widget-layer.md). append-child!/remove-child!/replace-child!/insert-child-after! each gained new :grid/:stack/:window-handle case branches, and the first three of those four functions gained an optional trailing structural-props argument threaded from glitter.gtk (see Bucket 3 below).

A post-round-11 fix, found while building examples/glitter/crud.clj: list-box-reorder-child!/flow-box-reorder-child! were reusing a widget pointer GTK had already disposed: gtk_list_box_remove/ gtk_flow_box_remove dispose the now-unreferenced wrapping row/ child, and BOTH wrappers' own dispose handlers unparent (and, with nothing else referencing it, finalize) their own child in turn (confirmed by reading gtk_list_box_row_dispose's and gtk_flow_box_child_dispose's C bodies directly). Fixed by bracketing the remove-then-reinsert in both functions with g-object-ref-sink/g-object-unref: the first actual call site for either binding in this codebase (both were already bound, inherited from glimmer's fork, but never previously used). See gtk-widget-layer.md.

See gtk-widget-layer.md for why all of this matters. - glitter.genum: forked from glimmer.genum, unmodified. - glitter.app: adapted from the non-reactive slice of glimmer.core (post-to-gui, on-gui, run*, run). glimmer's own mount/unmount!/ reload!/live-root/make-rerender-watcher are not ported; they're glimmer-reconciler-specific and have no equivalent in glitter's state-atom model.

Bucket 3: new to glitter

glitter.env: Jolt/GTK environment detection. Not a port of replicant.env, which concerns ClojureScript compiler presence/optimization (irrelevant to a Jolt/Chez host.
glitter.gtk) the IRender/IMemory GTK4 backend and mount!'s state-atom wiring. This is the file that makes glitter glitter rather than a Replicant-with-the-serial-numbers-filed-off; see architecture.md and gtk-widget-layer.md. Round 11 adds structural-child-props/structural-child-prop? and special-cases them in set-attribute/remove-attribute. A namespaced-prop finding (:grid/column-style keys are silently dropped by glitter.core's own set-attr/update-attr guard, upstream of IRender entirely) forced these onto plain, hyphenated keys instead, stashing matches on the CHILD's own el atom under :glitter/structural-props rather than routing them through glitter.widget/apply-props!. append-child, insert-before's fresh-insert branch, and replace-child all thread that stashed map through to glitter.widget's container-management functions as a new optional trailing argument; see gtk-widget-layer.md.
glitter.test-renderer: an in-memory fake IRender/IMemory, inspired by Replicant's mutation_log.cljc but separately implemented (a different protocol-composition mechanism; reify, not :extend-via-metadata; was required; see below).

Load-bearing implementation note: `reify`, never `:extend-via-metadata`

Replicant's own test helper (replicant.mutation-log) composes IRender and a logging concern via :extend-via-metadata true plus with-meta. This was verified broken under Jolt during this project's design phase: requiring replicant.mutation-log and calling its renderer throws No method create-element in replicant.protocols/IRender. Both glitter.gtk/renderer and glitter.test-renderer/renderer instead implement IRender and IMemory directly in a single reify form (reify genuinely dispatches under Jolt where :extend-via-metadata doesn't), and use with-meta only for auxiliary, non-protocol data (the event log and memory atoms in test-renderer).

Bucket 4: ported from nexus

The following files under src/glitter/ are ported from nexus, commit 5f6c93672f25d2a5b2a91ac3b65a921ecf8826b2, by Christian Johansen, Magnar Sveen, and Teodor Heggelund. MIT License: same terms as the Replicant bucket above (see NOTICE for the full text).

src/glitter/nexus.clj: src/nexus/core.cljc. One deliberate deviation: the three #?(:clj Exception :cljs :default) reader-conditionals collapse to a plain Exception catch (glitter targets Jolt only, no cljs).
src/glitter/nexus/registry.clj: src/nexus/registry.cljc. Byte-for-byte, zero deviations.
src/glitter/nexus/action_log.clj: a CONCEPT port, not a literal file: nexus's log-accumulation logic now lives inside nexus.inspector.cljc, entangled with dataspex.* rendering-protocol implementations with no glitter/GTK equivalent. This file ports the accumulation mechanism (the same nested :entries/:chronology tree) and drops every dp/*/dataspex call site. Three adaptations: now uses tick.core/now instead of java.util.Date. (jolt.time is already a project dependency); find-event reads :glitter/dom-event directly instead of hunting through dispatch-data's values for a DOM Event instance, since glitter's dispatch-data always IS the event map; measure-elapsed returns a plain {:ms .. :slow? ..} map instead of upstream's rounded Timing record (inspector.cljc's round-tenth): a correct adaptation, not an oversight, since Timing is a dataspex render type with no glitter equivalent, simply never written down until now.

Unlike Replicant/glimmer, nexus is a genuinely separate library (not glitter's own reconciler or its widget-layer fork): glitter depends on it conceptually the way an application depends on a dispatch library, which is why this is its own bucket rather than folded into Bucket 1 or 3. See nexus.md for the architecture this enables.

Keeping `NOTICE` current

Any new ported/forked file, or any new deviation in an already-ported file, gets a line added to the relevant bucket in NOTICE in the same commit as the code change, not as a follow-up. That file is what a downstream consumer or license auditor actually reads; this guide page is context for contributors, not a substitute.