adityamukho · Oct 24, 2026 · Oct 24, 2026
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
@@ -13,7 +13,7 @@ crate-type = ["cdylib", "rlib"]
 
 [dependencies]
 # Unreleased v3 core (format v8). Switches to version = "=3.0.0" at the v3.0.0 release.
-minigraf = { git = "https://github.com/project-minigraf/minigraf", rev = "949813ce27273d0c2820690df844e76951cb7996", features = ["browser"] }
+minigraf = { git = "https://github.com/project-minigraf/minigraf", rev = "5f2ba46e0c5a9954d90e52f60daaad2128d91973", features = ["browser"] }
 
 [features]
 browser = ["minigraf/browser"]

diff --git a/README.md b/README.md
@@ -43,6 +43,24 @@ try {
 }
 ```
 
+### Prepared queries
+
+`db.prepare(datalog)` parses a query once and returns a `BrowserPreparedQuery`;
+`execute(bindings)` returns the JSON `execute()` returns, and `query(bindings)` a
+`BrowserCursor`. Both are synchronous. Bindings are an object of slot name (without the
+`$`) to a boolean, a string, `null`, a `bigint` or a `number` (an integer when
+`Number.isInteger` accepts it, else a float), or a typed `{ type, value }` form:
+`{ type: 'float', value: 2 }`, `'keyword'`, `'ref'`, `{ type: 'entity', value: uuid }`,
+`{ type: 'txCount' | 'timestamp', value }` for `:as-of`, and `{ type: 'anyValidTime' }`
+for `:valid-at`. A value that is not a bind value throws a `TypeError`; a missing slot
+throws `[API-022]`, a slot in an attribute position `[API-023]`, and a value of the wrong
+kind `[API-024]`.
+
+```js
+const pq = db.prepare('(query [:find ?n :where [?e :age $age] [?e :name ?n]])')
+JSON.parse(pq.execute({ age: 30 })).results
+```
+
 ### Not available in the browser
 
 `BrowserDb` keeps its pages in memory and writes them to IndexedDB; it has no `.graph`

diff --git a/consumer-test/browser/contract.js b/consumer-test/browser/contract.js
@@ -23,6 +23,20 @@ async function run() {
   const rows = JSON.parse(await mem.execute('(query [:find ?n ?a :where [?e :name ?n] [?e :age ?a]])')).results
   check(JSON.stringify(rows) === '[["Alice",30]]', 'in-memory transact and query')
 
+  // Prepared query (minigraf#181): parse once, run with plain and typed values.
+  await mem.execute('(transact [[:bob :name "Bob"] [:bob :age 41]])')
+  const pq = mem.prepare('(query [:find ?n :where [?e :age $age] [?e :name ?n]])')
+  check(JSON.stringify(JSON.parse(pq.execute({ age: 30 })).results) === '[["Alice"]]', 'prepared query with a number')
+  check(JSON.stringify(JSON.parse(pq.execute({ age: 41n })).results) === '[["Bob"]]', 'prepared query with a bigint')
+  check(JSON.stringify(JSON.parse(pq.execute({ age: { type: 'integer', value: 30 } })).results) === '[["Alice"]]', 'prepared query with a typed value')
+  let missing
+  try {
+    pq.execute({})
+  } catch (e) {
+    missing = e
+  }
+  check(typeof missing === 'string' && missing.startsWith('[API-022] '), `a missing slot is API-022 (${missing})`)
+
   // Error type: a rejected promise whose reason starts with the error code,
   // as on every other API ("[PRS-011] Unknown command: nosuchcommand").
   let reason