diff --git a/src/lang/modifyAst.ts b/src/lang/modifyAst.ts
index b62b50122..fdfaf5815 100644
--- a/src/lang/modifyAst.ts
+++ b/src/lang/modifyAst.ts
@@ -335,12 +335,21 @@ export function sketchOnExtrudedFace(
   }
 }
 
-export const getLastIndex = (pathToNode: PathToNode): number => {
+export const getLastIndex = (pathToNode: PathToNode): number =>
+  splitPathAtLastIndex(pathToNode).index
+
+export function splitPathAtLastIndex(pathToNode: PathToNode): {
+  path: PathToNode
+  index: number
+} {
   const last = pathToNode[pathToNode.length - 1]
   if (typeof last === 'number') {
-    return last
+    return {
+      path: pathToNode.slice(0, -1),
+      index: last,
+    }
   }
-  return getLastIndex(pathToNode.slice(0, -1))
+  return splitPathAtLastIndex(pathToNode.slice(0, -1))
 }
 
 export function createLiteral(value: string | number): Literal {
diff --git a/src/lang/queryAst.test.ts b/src/lang/queryAst.test.ts
new file mode 100644
index 000000000..318493da1
--- /dev/null
+++ b/src/lang/queryAst.test.ts
@@ -0,0 +1,48 @@
+import { abstractSyntaxTree } from './abstractSyntaxTree'
+import { findAllPreviousVariables } from './queryAst'
+import { lexer } from './tokeniser'
+import { initPromise } from './rust'
+import { executor } from './executor'
+
+beforeAll(() => initPromise)
+
+describe('findAllPreviousVariables', () => {
+  it('should find all previous variables', () => {
+    const code = `const baseThick = 1
+const armAngle = 60
+
+const baseThickHalf = baseThick / 2
+const halfArmAngle = armAngle / 2
+
+const arrExpShouldNotBeIncluded = [1, 2, 3]
+const objExpShouldNotBeIncluded = { a: 1, b: 2, c: 3 }
+
+const part001 = startSketchAt([0, 0])
+  |> yLineTo(1, %)
+  |> xLine(3.84, %) // selection-range-7ish-before-this
+
+const variableBelowShouldNotBeIncluded = 3
+
+show(part001)`
+    const rangeStart = code.indexOf('// selection-range-7ish-before-this') - 7
+    const ast = abstractSyntaxTree(lexer(code))
+    const programMemory = executor(ast)
+
+    const { variables, bodyPath, insertIndex } = findAllPreviousVariables(
+      ast,
+      programMemory,
+      [rangeStart, rangeStart]
+    )
+    expect(variables).toEqual([
+      { key: 'baseThick', value: 1 },
+      { key: 'armAngle', value: 60 },
+      { key: 'baseThickHalf', value: 0.5 },
+      { key: 'halfArmAngle', value: 30 },
+      // no arrExpShouldNotBeIncluded, variableBelowShouldNotBeIncluded etc
+    ])
+    // there are 4 number variables and 2 non-number variables before the sketch var
+    // ∴ the insert index should be 6
+    expect(insertIndex).toEqual(6)
+    expect(bodyPath).toEqual(['body'])
+  })
+})
diff --git a/src/lang/queryAst.ts b/src/lang/queryAst.ts
index ef8c893c2..f0d1ff062 100644
--- a/src/lang/queryAst.ts
+++ b/src/lang/queryAst.ts
@@ -1,6 +1,7 @@
-import { PathToNode } from './executor'
+import { PathToNode, ProgramMemory } from './executor'
 import { Range } from '../useStore'
 import { Program } from './abstractSyntaxTree'
+import { splitPathAtLastIndex } from './modifyAst'
 
 export function getNodeFromPath<T>(
   node: Program,
@@ -133,3 +134,43 @@ export function getNodePathFromSourceRange(
   }
   return path
 }
+
+interface PrevVariable<T> {
+  key: string
+  value: T
+}
+
+export function findAllPreviousVariables(
+  ast: Program,
+  programMemory: ProgramMemory,
+  sourceRange: Range,
+  type: 'number' | 'string' = 'number'
+): {
+  variables: PrevVariable<typeof type extends 'number' ? number : string>[]
+  bodyPath: PathToNode
+  insertIndex: number
+} {
+  const path = getNodePathFromSourceRange(ast, sourceRange)
+  const { path: pathToDec } = getNodeFromPath(ast, path, 'VariableDeclaration')
+  const { index: insertIndex, path: bodyPath } = splitPathAtLastIndex(pathToDec)
+
+  const { node: bodyItems } = getNodeFromPath<Program['body']>(ast, bodyPath)
+
+  const variables: PrevVariable<any>[] = []
+  bodyItems.forEach((item) => {
+    if (item.type !== 'VariableDeclaration' || item.end > sourceRange[0]) return
+    const varName = item.declarations[0].id.name
+    const varValue = programMemory?.root[varName]
+    if (typeof varValue?.value !== type) return
+    variables.push({
+      key: varName,
+      value: varValue.value,
+    })
+  })
+
+  return {
+    insertIndex,
+    bodyPath: bodyPath,
+    variables,
+  }
+}