diff --git a/components.json b/components.json
index b353778e90..0180538021 100644
--- a/components.json
+++ b/components.json
@@ -346,6 +346,10 @@
 			"title": "Content-Security-Policy",
 			"owner": "ScottHelme"
 		},
+		"cql": {
+			"title": "Contextual Query Language",
+			"owner": "Querela"
+		},
 		"cooklang": {
 			"title": "Cooklang",
 			"owner": "ahue"
diff --git a/components/prism-cql.js b/components/prism-cql.js
new file mode 100644
index 0000000000..1dc97ef7a3
--- /dev/null
+++ b/components/prism-cql.js
@@ -0,0 +1,114 @@
+(function (Prism) {
+
+	var boolExp = /\b(?:AND|NOT|OR|PROX)\b/i;
+	var stringExp = /(?:"(?:\\[\s\S]|(?!")[^\\])*")/;
+	var wordExp = /[^\s()=<>"\/]+/;
+	var identifierExp = RegExp('(?:' + stringExp.source + '|' + wordExp.source + ')');
+
+	var comparitorNamedExp = identifierExp;
+	var comparitorSymbolExp = /(?:<>|[=><]=?)/;
+	var comparitorExp = RegExp('(?:' + comparitorSymbolExp.source + '|' + comparitorNamedExp.source + ')');
+
+	var modifierExp = RegExp('/\\s*' + identifierExp.source + '(?:\\s*' + comparitorSymbolExp.source + '\\s*' + identifierExp.source + ')?');
+	var modifierListExp = RegExp('(?:\\s*' + modifierExp.source + ')*');
+
+	var relationExp = RegExp(comparitorExp.source + modifierListExp.source);
+
+	var modifier = {
+		pattern: modifierExp,
+		inside: {
+			'modifier': {
+				pattern: RegExp('(/\\s*)' + identifierExp.source),
+				lookbehind: true,
+				alias: 'property',
+			},
+			'value': {
+				pattern: RegExp(identifierExp.source + '$'),
+				alias: 'string',
+			},
+			'comparitor': {
+				pattern: comparitorSymbolExp,
+				alias: 'operator',
+			},
+			'punctuation': /\//,
+		}
+	};
+
+	var searchClause = {
+		pattern: RegExp('(?:' + identifierExp.source + '\\s*' + relationExp.source + '\\s*)?' + identifierExp.source),
+		inside: {
+			// required last part, search term
+			'term': {
+				pattern: RegExp(identifierExp.source + '(?!.)'),
+				alias: 'string',
+			},
+			// optional index with relation
+			'index': {
+				pattern: RegExp('^' + identifierExp.source),
+				alias: 'property',
+			},
+			'relation-modifier': modifier,
+			'relation': {
+				pattern: comparitorExp,
+				alias: 'operator',
+			},
+		},
+	};
+
+	var boolClause = {
+		pattern: RegExp(boolExp.source + modifierListExp.source, 'i'),
+		inside: {
+			'boolean': {
+				pattern: boolExp,
+				alias: 'operator'
+			},
+			'boolean-modifier': modifier,
+		},
+	};
+
+	var prefix = {
+		pattern: RegExp('(^\\s*)>\\s*(?:' + identifierExp.source + '\\s*=\\s*)?' + identifierExp.source),
+		lookbehind: true,
+		inside: {
+			'uri': {
+				pattern: RegExp(identifierExp.source + '$'),
+				alias: 'string',
+			},
+			'prefix': {
+				pattern: identifierExp,
+				alias: 'property',
+			},
+			'punctuation': /[>=]/,
+		}
+	};
+
+	var sortby = {
+		// XXX: too complex exponential/polynomial backtracking possible ...
+		//pattern: RegExp('sortby(?:\\s*' + identifierExp.source + modifierListExp.source + ')+\\s*$', 'i'),
+		pattern: RegExp('(^|\\s)sortby\\b(?:' + identifierExp.source + '\\b|[\\s=></])+$', 'i'),
+		lookbehind: true,
+		inside: {
+			'keyword': /sortby/i,
+			'sortby-index-modifier': modifier,
+			'index': {
+				pattern: identifierExp,
+				alias: 'property',
+			}
+		}
+	};
+
+	Prism.languages['cql'] = {
+		// prefix / suffix
+		'prefix': prefix,
+		'sortby': sortby,
+
+		// conjuctions
+		'bool-group': boolClause,
+		// search clause triples
+		'search-clause': searchClause,
+
+		// grouping
+		'punctuation': /[()]/,
+	};
+
+}(Prism));
diff --git a/examples/prism-cql.html b/examples/prism-cql.html
new file mode 100644
index 0000000000..3caa7a65fe
--- /dev/null
+++ b/examples/prism-cql.html
@@ -0,0 +1,60 @@
+<h2>CQL Query</h2>
+
+<pre><code>dc.title any fish</code></pre>
+<pre><code>dc.title any fish or dc.creator any sanderson</code></pre>
+<pre><code>dc.title any fish sortBy dc.date/sort.ascending</code></pre>
+<pre><code>> dc = "info:srw/context-sets/1/dc-v1.1" dc.title any fish</code></pre>
+
+<h2>Search Clause</h2>
+
+<pre><code>dc.title any fish</code></pre>
+<pre><code>fish</code></pre>
+<pre><code>cql.serverChoice = fish</code></pre>
+
+<h2>Search Term</h2>
+
+<pre><code>"fish"</code></pre>
+<pre><code>fish</code></pre>
+<pre><code>"squirrels fish"</code></pre>
+<pre><code>""</code></pre>
+
+<h2>Index Name</h2>
+
+<pre><code>title any fish</code></pre>
+<pre><code>dc.title any fish</code></pre>
+
+<h2>Relation</h2>
+
+<pre><code>dc.title any fish</code></pre>
+<pre><code>dc.title cql.any fish</code></pre>
+
+<h2>Relation Modifiers</h2>
+
+<pre><code>dc.title any/relevant fish</code></pre>
+<pre><code>dc.title any/ relevant /cql.string fish</code></pre>
+<pre><code>dc.title any/rel.algorithm=cori fish</code></pre>
+
+<h2>Boolean Operators</h2>
+
+<pre><code>dc.title any fish or dc.creator any sanderson</code></pre>
+<pre><code>dc.title any fish or (dc.creator any sanderson and dc.identifier = "id:1234567")</code></pre>
+
+<h2>Boolean Modifiers</h2>
+
+<pre><code>dc.title any fish or/rel.combine=sum dc.creator any sanderson</code></pre>
+<pre><code>dc.title any fish prox/unit=word/distance&gt;3 dc.title any squirrel</code></pre>
+
+<h2>Sorting</h2>
+
+<pre><code>"cat" sortBy dc.title</code></pre>
+<pre><code>"dinosaur" sortBy dc.date/sort.descending dc.title/sort.ascending</code></pre>
+
+<h2>Prefix Assignment</h2>
+
+<pre><code>&gt; dc = "http://deepcustard.org/" dc.custardDepth &gt; 10</code></pre>
+<pre><code>&gt; "http://deepcustard.org/" custardDepth &gt; 10</code></pre>
+
+<h2>Case Insensitive</h2>
+
+<pre><code>dC.tiTlE any fish</code></pre>
+<pre><code>dc.TitlE Any/rEl.algOriThm=cori fish soRtbY Dc.TitlE </code></pre>
diff --git a/tests/languages/cql/boolean_modifiers.test b/tests/languages/cql/boolean_modifiers.test
new file mode 100644
index 0000000000..4ef945389f
--- /dev/null
+++ b/tests/languages/cql/boolean_modifiers.test
@@ -0,0 +1,57 @@
+dc.title any fish or/rel.combine=sum dc.creator any sanderson
+
+dc.title any fish prox/unit=word/distance>3 dc.title any squirrel
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]],
+	["bool-group", [
+		["boolean", "or"],
+		["boolean-modifier", [
+			["punctuation", "/"],
+			["modifier", "rel.combine"],
+			["comparitor", "="],
+			["value", "sum"]
+		]]
+	]],
+	["search-clause", [
+		["index", "dc.creator"],
+		["relation", "any"],
+		["term", "sanderson"]
+	]],
+
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]],
+	["bool-group", [
+		["boolean", "prox"],
+		["boolean-modifier", [
+			["punctuation", "/"],
+			["modifier", "unit"],
+			["comparitor", "="],
+			["value", "word"]
+		]],
+		["boolean-modifier", [
+			["punctuation", "/"],
+			["modifier", "distance"],
+			["comparitor", ">"],
+			["value", "3"]
+		]]
+	]],
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "squirrel"]
+	]]
+]
+
+----------------------------------------------------
+
+Boolean modifiers.
diff --git a/tests/languages/cql/boolean_operators.test b/tests/languages/cql/boolean_operators.test
new file mode 100644
index 0000000000..9e66c66dd4
--- /dev/null
+++ b/tests/languages/cql/boolean_operators.test
@@ -0,0 +1,49 @@
+dc.title any fish or dc.creator any sanderson
+
+dc.title any fish or (dc.creator any sanderson and dc.identifier = "id:1234567")
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]],
+	["bool-group", [
+		["boolean", "or"]
+	]],
+	["search-clause", [
+		["index", "dc.creator"],
+		["relation", "any"],
+		["term", "sanderson"]
+	]],
+
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]],
+	["bool-group", [
+		["boolean", "or"]
+	]],
+	["punctuation", "("],
+	["search-clause", [
+		["index", "dc.creator"],
+		["relation", "any"],
+		["term", "sanderson"]
+	]],
+	["bool-group", [
+		["boolean", "and"]
+	]],
+	["search-clause", [
+		["index", "dc.identifier"],
+		["relation", "="],
+		["term", "\"id:1234567\""]
+	]],
+	["punctuation", ")"]
+]
+
+----------------------------------------------------
+
+Boolean operators.
diff --git a/tests/languages/cql/case_insensitive.test b/tests/languages/cql/case_insensitive.test
new file mode 100644
index 0000000000..6fe598ed24
--- /dev/null
+++ b/tests/languages/cql/case_insensitive.test
@@ -0,0 +1,33 @@
+dC.tiTlE any fish
+
+dc.TitlE Any/rEl.algOriThm=cori fish soRtbY Dc.TitlE
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["index", "dC.tiTlE"],
+		["relation", "any"],
+		["term", "fish"]
+	]],
+
+	["search-clause", [
+		["index", "dc.TitlE"],
+		["relation", "Any"],
+		["relation-modifier", [
+			["punctuation", "/"],
+			["modifier", "rEl.algOriThm"],
+			["comparitor", "="],
+			["value", "cori"]
+		]],
+		["term", "fish"]
+	]],
+	["sortby", [
+		["keyword", "soRtbY"],
+		["index", "Dc.TitlE"]
+	]]
+]
+
+----------------------------------------------------
+
+Case Insenstivity.
diff --git a/tests/languages/cql/clause_feature_1.test b/tests/languages/cql/clause_feature_1.test
new file mode 100644
index 0000000000..dcbbd8c602
--- /dev/null
+++ b/tests/languages/cql/clause_feature_1.test
@@ -0,0 +1,15 @@
+dc.title any fish
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]]
+]
+
+----------------------------------------------------
+
+Search clauses.
diff --git a/tests/languages/cql/clause_feature_2.test b/tests/languages/cql/clause_feature_2.test
new file mode 100644
index 0000000000..031ce22987
--- /dev/null
+++ b/tests/languages/cql/clause_feature_2.test
@@ -0,0 +1,13 @@
+fish
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["term", "fish"]
+	]]
+]
+
+----------------------------------------------------
+
+Search clauses.
diff --git a/tests/languages/cql/clause_feature_3.test b/tests/languages/cql/clause_feature_3.test
new file mode 100644
index 0000000000..e90ec2f820
--- /dev/null
+++ b/tests/languages/cql/clause_feature_3.test
@@ -0,0 +1,15 @@
+cql.serverChoice = fish
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["index", "cql.serverChoice"],
+		["relation", "="],
+		["term", "fish"]
+	]]
+]
+
+----------------------------------------------------
+
+Search clauses.
diff --git a/tests/languages/cql/index_feature.test b/tests/languages/cql/index_feature.test
new file mode 100644
index 0000000000..d0c8b12981
--- /dev/null
+++ b/tests/languages/cql/index_feature.test
@@ -0,0 +1,23 @@
+title any fish
+
+dc.title any fish
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["index", "title"],
+		["relation", "any"],
+		["term", "fish"]
+	]],
+
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]]
+]
+
+----------------------------------------------------
+
+Index names.
diff --git a/tests/languages/cql/prefix_feature_1.test b/tests/languages/cql/prefix_feature_1.test
new file mode 100644
index 0000000000..98515b798c
--- /dev/null
+++ b/tests/languages/cql/prefix_feature_1.test
@@ -0,0 +1,21 @@
+> dc = "info:srw/context-sets/1/dc-v1.1" dc.title any fish
+
+----------------------------------------------------
+
+[
+	["prefix", [
+		["punctuation", ">"],
+		["prefix", "dc"],
+		["punctuation", "="],
+		["uri", "\"info:srw/context-sets/1/dc-v1.1\""]
+	]],
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]]
+]
+
+----------------------------------------------------
+
+Prefix assignments.
diff --git a/tests/languages/cql/prefix_feature_2.test b/tests/languages/cql/prefix_feature_2.test
new file mode 100644
index 0000000000..3c6a572de7
--- /dev/null
+++ b/tests/languages/cql/prefix_feature_2.test
@@ -0,0 +1,21 @@
+> dc = "http://deepcustard.org/" dc.custardDepth > 10
+
+----------------------------------------------------
+
+[
+	["prefix", [
+		["punctuation", ">"],
+		["prefix", "dc"],
+		["punctuation", "="],
+		["uri", "\"http://deepcustard.org/\""]
+	]],
+	["search-clause", [
+		["index", "dc.custardDepth"],
+		["relation", ">"],
+		["term", "10"]
+	]]
+]
+
+----------------------------------------------------
+
+Prefix assignments.
diff --git a/tests/languages/cql/prefix_feature_3.test b/tests/languages/cql/prefix_feature_3.test
new file mode 100644
index 0000000000..c0e8c247a4
--- /dev/null
+++ b/tests/languages/cql/prefix_feature_3.test
@@ -0,0 +1,19 @@
+> "http://deepcustard.org/" custardDepth > 10
+
+----------------------------------------------------
+
+[
+	["prefix", [
+		["punctuation", ">"],
+		["uri", "\"http://deepcustard.org/\""]
+	]],
+	["search-clause", [
+		["index", "custardDepth"],
+		["relation", ">"],
+		["term", "10"]
+	]]
+]
+
+----------------------------------------------------
+
+Prefix assignments.
diff --git a/tests/languages/cql/relation_feature.test b/tests/languages/cql/relation_feature.test
new file mode 100644
index 0000000000..2ef005bfba
--- /dev/null
+++ b/tests/languages/cql/relation_feature.test
@@ -0,0 +1,23 @@
+dc.title any fish
+
+dc.title cql.any fish
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]],
+
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "cql.any"],
+		["term", "fish"]
+	]]
+]
+
+----------------------------------------------------
+
+Relations.
diff --git a/tests/languages/cql/relation_modifiers.test b/tests/languages/cql/relation_modifiers.test
new file mode 100644
index 0000000000..9a11f81eb3
--- /dev/null
+++ b/tests/languages/cql/relation_modifiers.test
@@ -0,0 +1,49 @@
+dc.title any/relevant fish
+
+dc.title any/ relevant /cql.string fish
+
+dc.title any/rel.algorithm=cori fish
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["relation-modifier", [
+			["punctuation", "/"],
+			["modifier", "relevant"]
+		]],
+		["term", "fish"]
+	]],
+
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["relation-modifier", [
+			["punctuation", "/"],
+			["modifier", "relevant"]
+		]],
+		["relation-modifier", [
+			["punctuation", "/"],
+			["modifier", "cql.string"]
+		]],
+		["term", "fish"]
+	]],
+
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["relation-modifier", [
+			["punctuation", "/"],
+			["modifier", "rel.algorithm"],
+			["comparitor", "="],
+			["value", "cori"]
+		]],
+		["term", "fish"]
+	]]
+]
+
+----------------------------------------------------
+
+Relation modifiers.
diff --git a/tests/languages/cql/sort_feature_1.test b/tests/languages/cql/sort_feature_1.test
new file mode 100644
index 0000000000..24ad724b98
--- /dev/null
+++ b/tests/languages/cql/sort_feature_1.test
@@ -0,0 +1,23 @@
+dc.title any fish sortBy dc.date/sort.ascending
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]],
+	["sortby", [
+		["keyword", "sortBy"],
+		["index", "dc.date"],
+		["sortby-index-modifier", [
+			["punctuation", "/"],
+			["modifier", "sort.ascending"]
+		]]
+	]]
+]
+
+----------------------------------------------------
+
+Sorting.
diff --git a/tests/languages/cql/sort_feature_2.test b/tests/languages/cql/sort_feature_2.test
new file mode 100644
index 0000000000..b1da8feb85
--- /dev/null
+++ b/tests/languages/cql/sort_feature_2.test
@@ -0,0 +1,17 @@
+"cat" sortBy dc.title
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["term", "\"cat\""]
+	]],
+	["sortby", [
+		["keyword", "sortBy"],
+		["index", "dc.title"]
+	]]
+]
+
+----------------------------------------------------
+
+Sorting.
diff --git a/tests/languages/cql/sort_feature_3.test b/tests/languages/cql/sort_feature_3.test
new file mode 100644
index 0000000000..8c542c67cd
--- /dev/null
+++ b/tests/languages/cql/sort_feature_3.test
@@ -0,0 +1,26 @@
+"dinosaur" sortBy dc.date/sort.descending dc.title/sort.ascending
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["term", "\"dinosaur\""]
+	]],
+	["sortby", [
+		["keyword", "sortBy"],
+		["index", "dc.date"],
+		["sortby-index-modifier", [
+			["punctuation", "/"],
+			["modifier", "sort.descending"]
+		]],
+		["index", "dc.title"],
+		["sortby-index-modifier", [
+			["punctuation", "/"],
+			["modifier", "sort.ascending"]
+		]]
+	]]
+]
+
+----------------------------------------------------
+
+Sorting.
diff --git a/tests/languages/cql/spec_1.test b/tests/languages/cql/spec_1.test
new file mode 100644
index 0000000000..42c53dab87
--- /dev/null
+++ b/tests/languages/cql/spec_1.test
@@ -0,0 +1,45 @@
+dc.title any fish
+dc.title any fish or dc.creator any sanderson
+dc.title any fish sortBy dc.date/sort.ascending
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]],
+
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]],
+	["bool-group", [
+		["boolean", "or"]
+	]],
+	["search-clause", [
+		["index", "dc.creator"],
+		["relation", "any"],
+		["term", "sanderson"]
+	]],
+
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]],
+	["sortby", [
+		["keyword", "sortBy"],
+		["index", "dc.date"],
+		["sortby-index-modifier", [
+			["punctuation", "/"],
+			["modifier", "sort.ascending"]
+		]]
+	]]
+]
+
+----------------------------------------------------
+
+Some examples from SRU CQL spec.
diff --git a/tests/languages/cql/spec_2.test b/tests/languages/cql/spec_2.test
new file mode 100644
index 0000000000..26cbf6e51c
--- /dev/null
+++ b/tests/languages/cql/spec_2.test
@@ -0,0 +1,21 @@
+> dc = "info:srw/context-sets/1/dc-v1.1" dc.title any fish
+
+----------------------------------------------------
+
+[
+	["prefix", [
+		["punctuation", ">"],
+		["prefix", "dc"],
+		["punctuation", "="],
+		["uri", "\"info:srw/context-sets/1/dc-v1.1\""]
+	]],
+	["search-clause", [
+		["index", "dc.title"],
+		["relation", "any"],
+		["term", "fish"]
+	]]
+]
+
+----------------------------------------------------
+
+Some examples from SRU CQL spec.
diff --git a/tests/languages/cql/term_feature_1.test b/tests/languages/cql/term_feature_1.test
new file mode 100644
index 0000000000..0db77935b2
--- /dev/null
+++ b/tests/languages/cql/term_feature_1.test
@@ -0,0 +1,13 @@
+"fish"
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["term", "\"fish\""]
+	]]
+]
+
+----------------------------------------------------
+
+Search terms.
diff --git a/tests/languages/cql/term_feature_2.test b/tests/languages/cql/term_feature_2.test
new file mode 100644
index 0000000000..ee386d3c93
--- /dev/null
+++ b/tests/languages/cql/term_feature_2.test
@@ -0,0 +1,13 @@
+fish
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["term", "fish"]
+	]]
+]
+
+----------------------------------------------------
+
+Search terms.
diff --git a/tests/languages/cql/term_feature_3.test b/tests/languages/cql/term_feature_3.test
new file mode 100644
index 0000000000..d9230cbe0e
--- /dev/null
+++ b/tests/languages/cql/term_feature_3.test
@@ -0,0 +1,13 @@
+"squirrels fish"
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["term", "\"squirrels fish\""]
+	]]
+]
+
+----------------------------------------------------
+
+Search terms.
diff --git a/tests/languages/cql/term_feature_4.test b/tests/languages/cql/term_feature_4.test
new file mode 100644
index 0000000000..2fe63c68e3
--- /dev/null
+++ b/tests/languages/cql/term_feature_4.test
@@ -0,0 +1,13 @@
+""
+
+----------------------------------------------------
+
+[
+	["search-clause", [
+		["term", "\"\""]
+	]]
+]
+
+----------------------------------------------------
+
+Search terms.