diff --git a/packages/language-gfm/lib/main.js b/packages/language-gfm/lib/main.js
index f85b2f4cd..1ddb58d05 100644
--- a/packages/language-gfm/lib/main.js
+++ b/packages/language-gfm/lib/main.js
@@ -23,13 +23,11 @@ exports.activate = () => {
     languageScope: null
   });
 
-  // Create one HTML injection layer for all block-level HTML nodes.
+  // A separate injection layer for each block-level HTML node.
   atom.grammars.addInjectionPoint('source.gfm', {
-    type: 'document',
+    type: 'html_block',
     language: () => 'html',
-    content(node) {
-      return node.descendantsOfType('html_block');
-    },
+    content: (node) => node,
     includeChildren: true
   });
 
diff --git a/packages/language-ruby/grammars/modern-tree-sitter-ruby.cson b/packages/language-ruby/grammars/modern-tree-sitter-ruby.cson
index 928fda052..164e0ed95 100644
--- a/packages/language-ruby/grammars/modern-tree-sitter-ruby.cson
+++ b/packages/language-ruby/grammars/modern-tree-sitter-ruby.cson
@@ -6,7 +6,7 @@ parser: 'tree-sitter-ruby'
 injectionRegex: 'rb|ruby|RB|RUBY'
 
 treeSitter:
-  parserSource: 'github:tree-sitter/tree-sitter-ruby#4d9ad3f010fdc47a8433adcf9ae30c8eb8475ae7'
+  parserSource: 'github:tree-sitter/tree-sitter-ruby#9d86f3761bb30e8dcc81e754b81d3ce91848477e'
   grammar: 'tree-sitter-ruby/tree-sitter-ruby.wasm'
   highlightsQuery: 'tree-sitter-ruby/highlights.scm'
   localsQuery: 'tree-sitter-ruby/locals.scm'
diff --git a/packages/language-ruby/grammars/tree-sitter-ruby/tree-sitter-ruby.wasm b/packages/language-ruby/grammars/tree-sitter-ruby/tree-sitter-ruby.wasm
index c4818c3ce..bfca703c3 100755
Binary files a/packages/language-ruby/grammars/tree-sitter-ruby/tree-sitter-ruby.wasm and b/packages/language-ruby/grammars/tree-sitter-ruby/tree-sitter-ruby.wasm differ
diff --git a/packages/language-sass/grammars/modern-tree-sitter-scss.cson b/packages/language-sass/grammars/modern-tree-sitter-scss.cson
new file mode 100644
index 000000000..60d69c021
--- /dev/null
+++ b/packages/language-sass/grammars/modern-tree-sitter-scss.cson
@@ -0,0 +1,28 @@
+name: 'SCSS'
+scopeName: 'source.css.scss'
+type: 'modern-tree-sitter'
+# Built from the fork at savetheclocktower/tree-sitter-scss.
+parser: 'tree-sitter-scss'
+
+fileTypes: [
+  'scss'
+  'css.scss'
+  'css.scss.erb'
+  'scss.erb'
+  'scss.liquid'
+]
+
+injectionRegex: '^(scss|SCSS)$'
+
+treeSitter:
+  parserSource: 'github:savetheclocktower/tree-sitter-scss#090d25a5fc829ce6956201cf55ab6b6eacad999c'
+  grammar: 'tree-sitter/tree-sitter-scss.wasm'
+  highlightsQuery: 'tree-sitter/highlights.scm'
+  foldsQuery: 'tree-sitter/folds.scm'
+  indentsQuery: 'tree-sitter/indents.scm'
+  tagsQuery: 'tree-sitter/tags.scm'
+
+comments:
+  start: '//'
+  line: '//'
+  block: ['/*', '*/']
diff --git a/packages/language-sass/grammars/tree-sitter/folds.scm b/packages/language-sass/grammars/tree-sitter/folds.scm
new file mode 100644
index 000000000..a00841142
--- /dev/null
+++ b/packages/language-sass/grammars/tree-sitter/folds.scm
@@ -0,0 +1,2 @@
+
+(block) @fold
diff --git a/packages/language-sass/grammars/tree-sitter/highlights.scm b/packages/language-sass/grammars/tree-sitter/highlights.scm
new file mode 100644
index 000000000..a04a4384d
--- /dev/null
+++ b/packages/language-sass/grammars/tree-sitter/highlights.scm
@@ -0,0 +1,365 @@
+; WORKAROUND:
+;
+; When you're typing a new property name inside of a list, tree-sitter-css will
+; assume the thing you're typing is a descendant selector tag name until you
+; get to the colon. This prevents it from highlighting the incomplete line like
+; a selector tag name.
+
+(ERROR
+  (descendant_selector
+    (tag_name) @_IGNORE_
+    (#set! capture.final true)))
+
+(ERROR
+  (attribute_name) @_IGNORE_
+  (#set! capture.final true))
+
+((ERROR
+  (attribute_name) @invalid.illegal)
+  (#set! capture.final true))
+
+; COMMENTS
+; ========
+
+(comment) @comment.block.scss
+
+; Scope the block-comment delimiters (`/*` and `*/`).
+((comment) @punctuation.definition.comment.begin.scss
+  (#set! adjust.startAndEndAroundFirstMatchOf "^/\\*"))
+((comment) @punctuation.definition.comment.end.scss
+  (#set! adjust.startAndEndAroundFirstMatchOf "\\*/$"))
+
+(single_line_comment) @comment.line.double-slash.scss
+
+((single_line_comment) @punctuation.definition.comment.scss
+  (#set! adjust.startAndEndAroundFirstMatchOf "^//"))
+
+
+; SELECTORS
+; =========
+
+; (selectors "," @punctuation.separator.list.comma.scss)
+
+; The "div" in `div.foo {`.
+(tag_name) @entity.name.tag.scss
+; The "*" in `div > * {`.
+(universal_selector) @entity.name.tag.universal.scss
+; The "&" in `&:hover {`.
+(nesting_selector) @entity.name.tag.reference.scss
+
+; The "foo" in `div[attr=foo] {`.
+(attribute_selector (plain_value) @string.unquoted.scss)
+
+[
+  (child_selector ">")
+  (sibling_selector "~")
+  (adjacent_sibling_selector "+")
+] @keyword.operator.combinator.scss
+
+; The '.' in `.foo`.
+(class_selector "." @punctuation.definition.entity.scss)
+
+; The '.foo' in `.foo`.
+((class_selector) @entity.other.attribute-name.class.scss
+  (#set! adjust.startAt lastChild.previousSibling.startPosition))
+
+; The '%' in `%foo`.
+(placeholder_selector "%" @punctuation.definition.entity.scss)
+
+; The '%foo' in `%foo`.
+(placeholder_selector) @entity.other.attribute-name.class.scss
+
+
+(pseudo_class_selector [":" "::"] @punctuation.definition.entity.scss)
+
+; Pseudo-classes without arguments: the ":first-of-type" in `li:first-of-type`.
+((pseudo_class_selector (class_name) (arguments) .) @entity.other.attribute-name.pseudo-class.scss
+  (#set! adjust.startAt lastChild.previousSibling.previousSibling.startPosition)
+  (#set! adjust.endAt lastChild.previousSibling.endPosition)
+  (#set! capture.final true))
+
+; Pseudo-classes with arguments: the ":nth-of-type" in `li:nth-of-type(2n-1)`.
+((pseudo_class_selector (class_name) .) @entity.other.attribute-name.pseudo-class.scss
+  (#set! adjust.startAt lastChild.previousSibling.startPosition)
+  (#set! adjust.endAt lastChild.endPosition))
+
+(arguments
+  "(" @punctuation.definition.arguments.begin.bracket.round.scss
+  ")" @punctuation.definition.arguments.end.bracket.round.scss)
+
+(attribute_selector
+  "[" @punctuation.definition.entity.begin.bracket.square.scss
+  (attribute_name) @entity.other.attribute-name.scss
+  "]" @punctuation.definition.entity.end.bracket.square.scss)
+
+(attribute_selector
+  ["=" "^=" "$=" "~=" "|="] @keyword.operator.pattern.scss)
+
+
+; CSS VARIABLES
+; =============
+
+(declaration
+  (property_name) @variable.other.assignment.scss
+  (#match? @variable.other.assignment.scss "^--" )
+  (#set! capture.final true))
+
+
+; SCSS VARIABLES
+; ==============
+
+(variable_name) @variable.declaration.scss
+[(variable_value)] @variable.scss
+(argument_name) @variable.parameter.scss
+(each_statement (value) @variable.declaration.scss)
+
+; PROPERTIES
+; ==========
+
+; TODO: Is it worth it to try to maintain a list of recognized property names?
+; Would be useful to know if you've typo'd something, but it would be a
+; maintenance headache.
+(declaration
+  (property_name) @support.type.property-name.scss)
+
+(important) @keyword.other.important.css.scss
+(default) @keyword.other.default.scss
+
+; VALUES
+; ======
+
+; Strings
+; -------
+
+((string_value) @string.quoted.double.scss
+  (#match? @string.quoted.double.scss "^\"")
+  (#match? @string.quoted.double.scss "\"$"))
+
+((string_value) @string.quoted.single.scss
+  (#match? @string.quoted.single.scss "^'")
+  (#match? @string.quoted.single.scss "'$"))
+
+((string_value) @punctuation.definition.string.begin.scss
+  (#set! adjust.startAndEndAroundFirstMatchOf "^[\"']"))
+
+((string_value) @punctuation.definition.string.end.scss
+  (#set! adjust.startAndEndAroundFirstMatchOf "[\"']$"))
+
+
+; Property value constants
+; ------------------------
+
+; TODO: Is this worth it?
+((plain_value) @support.constant.property-value.scss
+  (#match? @support.constant.property-value.scss "^(above|absolute|active|add|additive|after-edge|alias|all|all-petite-caps|all-scroll|all-small-caps|alpha|alphabetic|alternate|alternate-reverse|always|antialiased|auto|auto-pos|available|avoid|avoid-column|avoid-page|avoid-region|backwards|balance|baseline|before-edge|below|bevel|bidi-override|blink|block|block-axis|block-start|block-end|bold|bolder|border|border-box|both|bottom|bottom-outside|break-all|break-word|bullets|butt|capitalize|caption|cell|center|central|char|circle|clip|clone|close-quote|closest-corner|closest-side|col-resize|collapse|color|color-burn|color-dodge|column|column-reverse|common-ligatures|compact|condensed|contain|content|content-box|contents|context-menu|contextual|copy|cover|crisp-edges|crispEdges|crosshair|cyclic|dark|darken|dashed|decimal|default|dense|diagonal-fractions|difference|digits|disabled|disc|discretionary-ligatures|distribute|distribute-all-lines|distribute-letter|distribute-space|dot|dotted|double|double-circle|downleft|downright|e-resize|each-line|ease|ease-in|ease-in-out|ease-out|economy|ellipse|ellipsis|embed|end|evenodd|ew-resize|exact|exclude|exclusion|expanded|extends|extra-condensed|extra-expanded|fallback|farthest-corner|farthest-side|fill|fill-available|fill-box|filled|fit-content|fixed|flat|flex|flex-end|flex-start|flip|flow-root|forwards|freeze|from-image|full-width|geometricPrecision|georgian|grab|grabbing|grayscale|grid|groove|hand|hanging|hard-light|help|hidden|hide|historical-forms|historical-ligatures|horizontal|horizontal-tb|hue|icon|ideograph-alpha|ideograph-numeric|ideograph-parenthesis|ideograph-space|ideographic|inactive|infinite|inherit|initial|inline|inline-axis|inline-block|inline-end|inline-flex|inline-grid|inline-list-item|inline-start|inline-table|inset|inside|inter-character|inter-ideograph|inter-word|intersect|invert|isolate|isolate-override|italic|jis04|jis78|jis83|jis90|justify|justify-all|kannada|keep-all|landscape|large|larger|left|light|lighten|lighter|line|line-edge|line-through|linear|linearRGB|lining-nums|list-item|local|loose|lowercase|lr|lr-tb|ltr|luminance|luminosity|main-size|mandatory|manipulation|manual|margin-box|match-parent|match-source|mathematical|max-content|medium|menu|message-box|middle|min-content|miter|mixed|move|multiply|n-resize|narrower|ne-resize|nearest-neighbor|nesw-resize|newspaper|no-change|no-clip|no-close-quote|no-common-ligatures|no-contextual|no-discretionary-ligatures|no-drop|no-historical-ligatures|no-open-quote|no-repeat|none|nonzero|normal|not-allowed|nowrap|ns-resize|numbers|numeric|nw-resize|nwse-resize|oblique|oldstyle-nums|open|open-quote|optimizeLegibility|optimizeQuality|optimizeSpeed|optional|ordinal|outset|outside|over|overlay|overline|padding|padding-box|page|painted|pan-down|pan-left|pan-right|pan-up|pan-x|pan-y|paused|petite-caps|pixelated|plaintext|pointer|portrait|pre|pre-line|pre-wrap|preserve-3d|progress|progressive|proportional-nums|proportional-width|proximity|radial|recto|region|relative|remove|repeat|repeat-[xy]|reset-size|reverse|revert|ridge|right|rl|rl-tb|round|row|row-resize|row-reverse|row-severse|rtl|ruby|ruby-base|ruby-base-container|ruby-text|ruby-text-container|run-in|running|s-resize|saturation|scale-down|screen|scroll|scroll-position|se-resize|semi-condensed|semi-expanded|separate|sesame|show|sideways|sideways-left|sideways-lr|sideways-right|sideways-rl|simplified|slashed-zero|slice|small|small-caps|small-caption|smaller|smooth|soft-light|solid|space|space-around|space-between|space-evenly|spell-out|square|sRGB|stacked-fractions|start|static|status-bar|swap|step-end|step-start|sticky|stretch|strict|stroke|stroke-box|style|sub|subgrid|subpixel-antialiased|subtract|super|sw-resize|symbolic|table|table-caption|table-cell|table-column|table-column-group|table-footer-group|table-header-group|table-row|table-row-group|tabular-nums|tb|tb-rl|text|text-after-edge|text-before-edge|text-bottom|text-top|thick|thin|titling-caps|top|top-outside|touch|traditional|transparent|triangle|ultra-condensed|ultra-expanded|under|underline|unicase|unset|upleft|uppercase|upright|use-glyph-orientation|use-script|verso|vertical|vertical-ideographic|vertical-lr|vertical-rl|vertical-text|view-box|visible|visibleFill|visiblePainted|visibleStroke|w-resize|wait|wavy|weight|whitespace|wider|words|wrap|wrap-reverse|x|x-large|x-small|xx-large|xx-small|y|zero|zoom-in|zoom-out)$"))
+
+; All property values that have special meaning in `font-family`.
+; TODO: Restrict these to be meaningful only when the property name is font-related?
+((plain_value) @support.constant.property-value.font-name.scss
+  (#match? @support.constant.property-value.font-name.scss "^(serif|sans-serif|monospace|cursive|fantasy|system-ui|ui-serif|ui-sans-serif|ui-monospace|ui-rounded|emoji|math|fangsong)$"))
+
+; All property values that have special meaning in `list-style-type`.
+; TODO: Restrict these to be meaningful only when the property name is `list-style-type`?
+((plain_value) @support.constant.property-value.list-style-type.scss
+  (#match? @support.constant.property-value.list-style-type.scss "^(arabic-indic|armenian|bengali|cambodian|circle|cjk-decimal|cjk-earthly-branch|cjk-heavenly-stem|cjk-ideographic|decimal|decimal-leading-zero|devanagari|disc|disclosure-closed|disclosure-open|ethiopic-halehame-am|ethiopic-halehame-ti-e[rt]|ethiopic-numeric|georgian|gujarati|gurmukhi|hangul|hangul-consonant|hebrew|hiragana|hiragana-iroha|japanese-formal|japanese-informal|kannada|katakana|katakana-iroha|khmer|korean-hangul-formal|korean-hanja-formal|korean-hanja-informal|lao|lower-alpha|lower-armenian|lower-greek|lower-latin|lower-roman|malayalam|mongolian|myanmar|oriya|persian|simp-chinese-formal|simp-chinese-informal|square|tamil|telugu|thai|tibetan|trad-chinese-formal|trad-chinese-informal|upper-alpha|upper-armenian|upper-latin|upper-roman|urdu)$"))
+
+; Numbers & units
+; ---------------
+
+; This node type appears to always be a hex color.
+(color_value) @constant.other.color.rgb-value.hex.scss
+
+[(integer_value) (float_value)] @constant.numeric.scss
+
+; All unit types with valid scope names.
+((unit) @keyword.other.unit._TEXT_.scss
+  (#match? @keyword.other.unit._TEXT_.scss "^(deg|grad|rad|turn|ch|cm|em|ex|fr|in|mm|mozmm|pc|pt|px|q|rem|vh|vmax|vmin|vw|dpi|dpcm|dpps|s|ms)$"))
+
+((unit) @keyword.other.unit.percentage.scss
+  (#eq? @keyword.other.unit.percentage.scss "%"))
+
+; The magic color value `currentColor`.
+((plain_value) @support.constant.color.current.scss
+  (#eq? @support.constant.color.current.scss "currentColor"))
+
+; Match the TM bundle's special treatment of named colors.
+((plain_value) @support.constant.color.w3c-standard-color-name.scss
+  (#match? @support.constant.color.w3c-standard-color-name.scss "^(aqua|black|blue|fuchsia|gray|green|lime|maroon|navy|olive|orange|purple|red|silver|teal|white|yellow)$"))
+
+((plain_value) @support.constant.color.w3c-extended-color-name.scss
+  (#match? @support.constant.color.w3c-extended-color-name.scss "^(aliceblue|antiquewhite|aquamarine|azure|beige|bisque|blanchedalmond|blueviolet|brown|burlywood|cadetblue|chartreuse|chocolate|coral|cornflowerblue|cornsilk|crimson|cyan|darkblue|darkcyan|darkgoldenrod|darkgray|darkgreen|darkgrey|darkkhaki|darkmagenta|darkolivegreen|darkorange|darkorchid|darkred|darksalmon|darkseagreen|darkslateblue|darkslategray|darkslategrey|darkturquoise|darkviolet|deeppink|deepskyblue|dimgray|dimgrey|dodgerblue|firebrick|floralwhite|forestgreen|gainsboro|ghostwhite|gold|goldenrod|greenyellow|grey|honeydew|hotpink|indianred|indigo|ivory|khaki|lavender|lavenderblush|lawngreen|lemonchiffon|lightblue|lightcoral|lightcyan|lightgoldenrodyellow|lightgray|lightgreen|lightgrey|lightpink|lightsalmon|lightseagreen|lightskyblue|lightslategray|lightslategrey|lightsteelblue|lightyellow|limegreen|linen|magenta|mediumaquamarine|mediumblue|mediumorchid|mediumpurple|mediumseagreen|mediumslateblue|mediumspringgreen|mediumturquoise|mediumvioletred|midnightblue|mintcream|mistyrose|moccasin|navajowhite|oldlace|olivedrab|orangered|orchid|palegoldenrod|palegreen|paleturquoise|palevioletred|papayawhip|peachpuff|peru|pink|plum|powderblue|rebeccapurple|rosybrown|royalblue|saddlebrown|salmon|sandybrown|seagreen|seashell|sienna|skyblue|slateblue|slategray|slategrey|snow|springgreen|steelblue|tan|thistle|tomato|transparent|turquoise|violet|wheat|whitesmoke|yellowgreen)$"))
+
+((plain_value) @invalid.deprecated.color.system.scss
+  (#match? @invalid.deprecated.color.system.scss "^(ActiveBorder|ActiveCaption|AppWorkspace|Background|ButtonFace|ButtonHighlight|ButtonShadow|ButtonText|CaptionText|GrayText|Highlight|HighlightText|InactiveBorder|InactiveCaption|InactiveCaptionText|InfoBackground|InfoText|Menu|MenuText|Scrollbar|ThreeDDarkShadow|ThreeDFace|ThreeDHighlight|ThreeDLightShadow|ThreeDShadow|Window|WindowFrame|WindowText)$"))
+
+; Builtins
+; --------
+
+(boolean_value) @constant.boolean._TEXT_.scss
+(null_value) @constant.language.null.scss
+
+
+; FUNCTIONS
+; =========
+
+((function_name) @support.function.var.css.scss
+  (arguments (plain_value) @variable.css.scss)
+  (#eq? @support.function.var.css.scss "var")
+  (#set! capture.final true))
+
+((function_name) @support.function._TEXT_.css.scss
+  (#match? @support.function._TEXT_.css.scss "^(abs|acos|annotation|asin|atan2?attr|blur|brightness|calc|character-variant|circle|clamp|color-contrast|color-mix|conic-gradient|contrast|cos|counters|cross-fade|cubic-bezier|device-cmyk|drop-shadow|element|ellipse|env|exp|format|grayscale|hsla?|hue-rotate|hwp|hypot|image|image-set|inset|invert|lab|lch|linear-gradient|local|log|matrix|matrix3d|max|min|minmax|mod|oklab|oklch|opacity|ornaments|paint|path|perspective|polygon|pow|radial-gradient|ray|rect|rem|repeat|repeating-(conic|linear|radial)-gradient|rgba?|rotate(3d)?|rotate(X|Y|Z)|round|saturate|scale(3d)?|scale(X|Y|Z)|sepia|sign|sin|skew(X|Y)?|sqrt|steps|styleset|stylistic|swash|symbols|tan|translate(3d)?|translate(X|Y|Z)|url)$")
+  (#set! capture.final true))
+
+((function_name) @support.other.function._TEXT_.scss)
+
+((function_name) @_IGNORE_
+  (arguments (plain_value) @string.unquoted.scss)
+  (#eq? @_IGNORE_ "url"))
+
+((module) @support.module._TEXT_.scss
+  (#match? @support.module._TEXT_.scss "^(color|list|map|math|meta|selector|string)$")
+  (#set! capture.final true))
+
+(module) @support.other.module.scss
+
+
+; MIXINS
+; ======
+
+(mixin_statement
+	(name) @entity.name.function.mixin.scss)
+
+(include_statement
+  (mixin_name) @support.other.function.mixin.scss)
+
+
+; AT-RULES
+; ========
+
+"@media" @keyword.control.at-rule.media.css.scss
+"@import" @keyword.control.at-rule.import.css.scss
+"@charset" @keyword.control.at-rule.charset.css.scss
+"@namespace" @keyword.control.at-rule.namespace.css.scss
+"@supports" @keyword.control.at-rule.supports.css.scss
+"@keyframes" @keyword.control.at-rule.keyframes.css.scss
+
+"@include" @keyword.control.at-rule.include.scss
+"@mixin" @keyword.control.at-rule.mixin.scss
+"@if" @keyword.control.at-rule.if.scss
+"@else" @keyword.control.at-rule.else.scss
+"@for" @keyword.control.at-rule.for.scss
+"@use" @keyword.control.at-rule.use.scss
+"@forward" @keyword.control.at-rule.forward.scss
+"@extend" @keyword.control.at-rule.extend.scss
+"@function" @keyword.control.at-rule.function.scss
+"@return" @keyword.control.at-rule.return.scss
+"@each" @keyword.control.at-rule.each.scss
+"@at-root" @keyword.control.at-rule.at-root.scss
+
+"@error" @keyword.directive.error.scss
+"@warn" @keyword.directive.warn.scss
+"@debug" @keyword.directive.debug.scss
+
+(each_statement "in" @keyword.control.in.scss)
+
+; The parser is permissive and supports at-rule keywords that don't currently
+; exist, so we'll set a fallback scope for those.
+((at_keyword) @keyword.control.at-rule.other.scss
+  (#set! capture.shy true))
+
+[(to) (from)] @keyword.control._TYPE_.css.scss
+
+(keyword_query) @support.constant.css.scss
+(feature_name) @support.constant.css.scss
+
+[
+  "as"
+  "from"
+  "through"
+] @keyword.control._TYPE_.scss
+
+
+(id_selector
+  "#" @punctuation.definition.entity.id.scss) @entity.other.attribute-name.id.scss
+
+((use_alias) @variable.language.alias.expanded.scss
+  (#eq? @variable.language.alias.expanded.scss "*")
+  (#set! capture.final true))
+
+(use_alias) @variable.other.alias.scss
+
+; FUNCTIONS
+; =========
+
+(function_statement (name) @entity.name.function.scss)
+
+
+; OPERATORS
+; =========
+
+; Used in `@media` queries.
+["and" "not" "only" "or"] @keyword.operator.logical._TYPE_.scss
+
+; Used in `calc()` and elsewhere.
+(binary_expression ["+" "-" "*" "/"] @keyword.operator.arithmetic.scss)
+
+"..." @keyword.operator.spread.scss
+
+; When `ERROR` is present here, it's typically because a rest parameter or
+; argument is not the last in the list. Indicate this to the user by marking
+; the '...' itself as invalid.
+(ERROR
+  [
+    (rest_parameter "..." @invalid.illegal.spread.scss)
+    (rest_argument "..." @invalid.illegal.spread.scss)
+  ]
+)
+
+
+; INTERPOLATION
+; =============
+
+(interpolation) @meta.embedded.line.interpolation.scss
+(interpolation "#{" @punctuation.section.embedded.begin.scss)
+(interpolation "}" @punctuation.section.embedded.end.scss)
+
+; OTHER STUFF
+; ===========
+
+(keyframes_statement
+  name: (keyframes_name) @entity.name.keyframes.css.scss)
+
+(nesting_value) @entity.other.tag.reference.scss
+
+; PUNCTUATION
+; ===========
+
+(parameters "(") @punctuation.definition.parameters.begin.brace.round.scss
+(parameters ")") @punctuation.definition.parameters.end.brace.round.scss
+
+"," @punctuation.separator.comma.scss
+":" @punctuation.separator.colon.scss
+";" @punctuation.separator.semicolon.scss
+
+("{" @punctuation.brace.curly.begin.scss
+  (#set! capture.shy))
+("}" @punctuation.brace.curly.end.scss
+  (#set! capture.shy))
+
+("(" @punctuation.brace.round.begin.scss
+  (#set! capture.shy))
+(")" @punctuation.brace.round.end.scss
+  (#set! capture.shy))
+
+(":" @punctuation.separator.key-value.scss
+  (#set! capture.shy))
+
+
+; SECTIONS
+; ========
+
+(rule_set (block) @meta.block.inside-selector.scss)
+((block) @meta.block.scss
+  (#set! capture.shy))
+(selectors) @meta.selector.scss
diff --git a/packages/language-sass/grammars/tree-sitter/indents.scm b/packages/language-sass/grammars/tree-sitter/indents.scm
new file mode 100644
index 000000000..dae6dde83
--- /dev/null
+++ b/packages/language-sass/grammars/tree-sitter/indents.scm
@@ -0,0 +1,3 @@
+
+"{" @indent
+"}" @dedent
diff --git a/packages/language-sass/grammars/tree-sitter/tags.scm b/packages/language-sass/grammars/tree-sitter/tags.scm
new file mode 100644
index 000000000..87679070c
--- /dev/null
+++ b/packages/language-sass/grammars/tree-sitter/tags.scm
@@ -0,0 +1,7 @@
+(rule_set (selectors) @name) @definition.selector
+
+(keyframes_statement (keyframes_name) @name) @definition.keyframes
+
+(mixin_statement (name) @name) @definition.mixin
+
+(function_statement (name) @name) @definition.function
diff --git a/packages/language-sass/grammars/tree-sitter/tree-sitter-scss.wasm b/packages/language-sass/grammars/tree-sitter/tree-sitter-scss.wasm
new file mode 100755
index 000000000..6ed858067
Binary files /dev/null and b/packages/language-sass/grammars/tree-sitter/tree-sitter-scss.wasm differ
diff --git a/packages/language-sass/lib/main.js b/packages/language-sass/lib/main.js
new file mode 100644
index 000000000..ea408cf95
--- /dev/null
+++ b/packages/language-sass/lib/main.js
@@ -0,0 +1,12 @@
+
+exports.consumeHyperlinkInjection = (hyperlink) => {
+  hyperlink.addInjectionPoint('source.css.scss', {
+    types: ['comment', 'single_line_comment']
+  });
+};
+
+exports.consumeTodoInjection = (todo) => {
+  todo.addInjectionPoint('source.css.scss', {
+    types: ['comment', 'single_line_comment']
+  });
+};
diff --git a/packages/language-sass/package.json b/packages/language-sass/package.json
index 293b3c7c8..cda7ec3f7 100644
--- a/packages/language-sass/package.json
+++ b/packages/language-sass/package.json
@@ -1,14 +1,27 @@
 {
   "name": "language-sass",
   "version": "0.62.2",
+  "main": "lib/main",
   "description": "Sass/SCSS language support in Atom",
   "license": "MIT",
   "engines": {
     "atom": "*",
-    "node": "*"
+    "node": ">=12"
   },
   "repository": "https://github.com/pulsar-edit/pulsar",
   "devDependencies": {
     "dedent": "^0.7.0"
+  },
+  "consumedServices": {
+    "hyperlink.injection": {
+      "versions": {
+        "0.1.0": "consumeHyperlinkInjection"
+      }
+    },
+    "todo.injection": {
+      "versions": {
+        "0.1.0": "consumeTodoInjection"
+      }
+    }
   }
 }
diff --git a/packages/language-sass/snippets/scss.cson b/packages/language-sass/snippets/scss.cson
new file mode 100644
index 000000000..9c31e1576
--- /dev/null
+++ b/packages/language-sass/snippets/scss.cson
@@ -0,0 +1,49 @@
+'.source.css.scss':
+  '!important':
+    prefix: '!'
+    body: 'i!important${:;}$0'
+  '@use':
+    prefix: 'use'
+    body: "@use '${1:file}'${2: as ${3:alias}};"
+  '@import':
+    prefix: 'import'
+    body: '@import "$0";'
+    description: "An enhanced version of CSS’s “@import” rule."
+    descriptionMoreURL: "https://sass-lang.com/documentation/at-rules/import/"
+  '@include':
+    prefix: 'include'
+    body: '@include ${1:mixin}${2:($3)};$0'
+    description: "Include a mixin into the current context."
+    descriptionMoreURL: "https://sass-lang.com/documentation/at-rules/mixin/"
+  '@extend':
+    prefix: 'extend'
+    body: '@extend ${1}$0';
+    description: "Tells one selector to inherit the styles of another."
+    descriptionMoreURL: "https://sass-lang.com/documentation/at-rules/extend/"
+  '@if':
+    prefix: 'if'
+    body: """
+    @if ${1:conditions} {
+      $0
+    }
+    """
+    description: "Controls whether or not its block gets evaluated."
+    descriptionMoreURL: "https://sass-lang.com/documentation/at-rules/control/if/"
+  '@mixin':
+    prefix: 'mixin'
+    body: """
+    @mixin ${1:name}${2:($3)} {
+      $0
+    }
+    """
+    description: "Include a mixin."
+    descriptionMoreURL: "https://sass-lang.com/documentation/at-rules/mixin/"
+  '@function':
+    prefix: 'fun'
+    body: """
+    @mixin ${1:name} {
+      $0
+    }
+    """
+    description: "Define your own function."
+    descriptionMoreURL: "https://sass-lang.com/documentation/at-rules/function/"
diff --git a/packages/language-sass/spec/sassdoc-spec.js b/packages/language-sass/spec/sassdoc-spec.js
index e87d07ef1..cc40b8498 100644
--- a/packages/language-sass/spec/sassdoc-spec.js
+++ b/packages/language-sass/spec/sassdoc-spec.js
@@ -1,15 +1,19 @@
 
-describe('SassDoc grammar', function() {
+describe('SassDoc grammar', function () {
   let grammar = null;
 
-  beforeEach(function() {
+  beforeEach(function () {
+    // There isn't a Tree-sitter grammar for SassDoc that I'm aware of. Users
+    // who expect thorough highlighting of SassDoc can add a scope-specific
+    // override to prefer the TextMate-style SCSS grammar.
+    atom.config.set('core.useTreeSitterParsers', false)
     waitsForPromise(() => atom.packages.activatePackage('language-sass'));
 
     runs(() => grammar = atom.grammars.grammarForScopeName('source.css.scss'));
   });
 
-  describe('block tags', function() {
-    it('tokenises simple tags', function() {
+  describe('block tags', function () {
+    it('tokenises simple tags', function () {
       const {tokens} = grammar.tokenizeLine('/// @deprecated');
       expect(tokens[0]).toEqual({value: '///', scopes: ['source.css.scss', 'comment.block.documentation.scss', 'punctuation.definition.comment.scss']});
       expect(tokens[1]).toEqual({value: ' ', scopes: ['source.css.scss', 'comment.block.documentation.scss']});
@@ -17,7 +21,7 @@ describe('SassDoc grammar', function() {
       expect(tokens[3]).toEqual({value: 'deprecated', scopes: ['source.css.scss', 'comment.block.documentation.scss', 'storage.type.class.sassdoc']});
   });
 
-    it('tokenises @param tags with a description', function() {
+    it('tokenises @param tags with a description', function () {
       const {tokens} = grammar.tokenizeLine('/// @param {type} $name - Description');
       expect(tokens[0]).toEqual({value: '///', scopes: ['source.css.scss', 'comment.block.documentation.scss', 'punctuation.definition.comment.scss']});
       expect(tokens[2]).toEqual({value: '@', scopes: ['source.css.scss', 'comment.block.documentation.scss', 'storage.type.class.sassdoc', 'punctuation.definition.block.tag.sassdoc']});
@@ -30,7 +34,7 @@ describe('SassDoc grammar', function() {
   });
 });
 
-  describe('highlighted examples', () => it('highlights SCSS after an @example tag', function() {
+  describe('highlighted examples', () => it('highlights SCSS after an @example tag', function () {
     const lines = grammar.tokenizeLines(`\
 ///
 /// @example scss - Description
diff --git a/packages/language-typescript/grammars/common/highlights.scm b/packages/language-typescript/grammars/common/highlights.scm
index 5b9d7cf53..73d34f2ee 100644
--- a/packages/language-typescript/grammars/common/highlights.scm
+++ b/packages/language-typescript/grammars/common/highlights.scm
@@ -18,16 +18,16 @@
   (identifier) @variable.other.assignment.import.namespace._LANG_)
 
 ; The "*" in `export * from 'bar'`
-(export_statement "*" @variable.other.assignment.export.all.js)
+(export_statement "*" @variable.other.assignment.export.all._LANG_)
 
 ; The "*" in `export * as Foo from 'bar'`
 (export_statement
-  (namespace_export "*" @variable.other.assignment.export.all.js))
+  (namespace_export "*" @variable.other.assignment.export.all._LANG_))
 
 ; The "*" in `export * as Foo from 'bar'`
 (export_statement
   (namespace_export
-    (identifier) @variable.other.assignment.export.alias.js))
+    (identifier) @variable.other.assignment.export.alias._LANG_))
 
 ; The "Foo" in `export { Foo }`
 (export_specifier
@@ -51,7 +51,7 @@
 ; =========
 
 (this) @variable.language.this._LANG_
-(super) @variable.language.super._LANG_._LANG_x
+(super) @variable.language.super._LANG_
 
 (required_parameter
   pattern: (identifier) @variable.parameter.with-default._LANG_
@@ -345,7 +345,7 @@
 
 "=>" @storage.type.arrow._LANG_
 
-; TODO: If I allow scopes like `storage.type.string._LANG_`, I will make a lot of
+; TODO: If I allow scopes like `storage.type.string.ts`, I will make a lot of
 ; text look like strings by accident. This really needs to be fixed in syntax
 ; themes.
 ;
@@ -764,10 +764,10 @@
 ) @meta.embedded.line.interpolation._LANG_
 
 (string
-  (escape_sequence) @constant.character.escape.js)
+  (escape_sequence) @constant.character.escape._LANG_)
 
 (template_string
-  (escape_sequence) @constant.character.escape.js)
+  (escape_sequence) @constant.character.escape._LANG_)
 
 
 ; CONSTANTS
@@ -817,16 +817,16 @@
 ; REGEX
 ; =====
 
-(regex) @string.regexp.js
+(regex) @string.regexp._LANG_
 (regex
-  "/" @punctuation.definition.string.begin.js
+  "/" @punctuation.definition.string.begin._LANG_
   (#is? test.first))
 
 (regex
-  "/" @punctuation.definition.string.end.js
+  "/" @punctuation.definition.string.end._LANG_
   (#is? test.last))
 
-(regex_flags) @keyword.other.js
+(regex_flags) @keyword.other._LANG_
 
 
 ; OPERATORS
@@ -837,26 +837,28 @@
 
 "=" @keyword.operator.assignment._LANG_
 (non_null_expression "!" @keyword.operator.non-null._LANG_)
-(unary_expression"!" @keyword.operator.unary._LANG_)
+(unary_expression "!" @keyword.operator.unary._LANG_)
 
 [
+  "&&="
+  "||="
+  "??="
   "+="
   "-="
   "*="
+  "**="
   "/="
   "%="
+  "^="
+  "&="
+  "|="
   "<<="
   ">>="
   ">>>="
-  "&="
-  "^="
-  "|="
-  "??="
-  "||="
 ] @keyword.operator.assignment.compound._LANG_
 
 (binary_expression
-  ["+" "-" "*" "/" "%"] @keyword.operator.arithmetic._LANG_)
+  ["/" "+" "-" "*" "**" "%"] @keyword.operator.arithmetic._LANG_)
 
 (unary_expression ["+" "-"] @keyword.operator.unary._LANG_)
 
@@ -866,15 +868,14 @@
     "==="
     "!="
     "!=="
-    ">="
-    "<="
-    ">"
-    "<"
   ] @keyword.operator.comparison._LANG_
 )
 
 ["++" "--"] @keyword.operator.increment._LANG_
 
+(binary_expression
+  [">=" "<=" ">" "<"] @keyword.operator.relational._LANG_)
+
 [
   "&&"
   "||"
@@ -902,6 +903,20 @@
 "." @keyword.operator.accessor._LANG_
 "?." @keyword.operator.accessor.optional-chaining._LANG_
 
+; Optional chaining is illegal…
+
+; …on the left-hand side of an assignment.
+(assignment_expression
+  left: (_) @_IGNORE_
+    (#set! prohibitsOptionalChaining true))
+
+; …within a `new` expression.
+(new_expression
+  constructor: (_) @_IGNORE_
+    (#set! prohibitsOptionalChaining true))
+
+((optional_chain) @invalid.illegal.optional-chain._LANG_
+  (#is? test.descendantOfNodeWithData prohibitsOptionalChaining))
 
 (ternary_expression
   ["?" ":"] @keyword.operator.ternary._LANG_
diff --git a/src/wasm-tree-sitter-language-mode.js b/src/wasm-tree-sitter-language-mode.js
index 922382d4f..b28fbc879 100644
--- a/src/wasm-tree-sitter-language-mode.js
+++ b/src/wasm-tree-sitter-language-mode.js
@@ -4501,7 +4501,7 @@ class NodeRangeSet {
   getNodeSpec(node, getChildren) {
     let { startIndex, endIndex, startPosition, endPosition, id } = node;
     let result = { startIndex, endIndex, startPosition, endPosition, id };
-    if (node.children && getChildren) {
+    if (getChildren && node.childCount > 0) {
       result.children = [];
       for (let child of node.children) {
         result.children.push(this.getNodeSpec(child, false));