# Roadmap: good next functions

Near-term useful features:

1. Engine UX polish
  - Show “SaxonJS loading…” when the large compiler file is first loaded.
  - Show compile time vs transform time separately.
  - Cache compiled SEF by stylesheet hash to avoid recompiling unchanged XSLT.
2. Parameters
  - Add UI for xsl:param.
  - Support string/number/boolean parameters first.
  - Later support XPath expressions.
3. Better diagnostics
  - Convert SaxonJS compiler/runtime errors into editor diagnostics.
  - Extract line/module info when available.
  - Jump from diagnostic to editor line.
4. Examples / templates
  - Identity transform.
  - Rename elements.
  - Extract table.
  - Namespace cleanup.
  - Grouping example.
  - XSLT 3.0 shallow-copy example.
5. Project files
  - Export/import a full local project JSON:
'''XML input
XSLT
output
engine
examples/tests
parameters'''
  - No uploads needed.
6. Test cases inside the app
  - Multiple XML inputs per stylesheet.
  - Expected output assertions.
  - Diff expected vs actual.
  - “Run all tests” button.
7. Diff views
  - XML input vs output.
  - Previous output vs current output.
  - Pretty XML diff.
8. Explain mode
  - Start with static analysis:
'''template match → output node candidates'''
  - Later add instrumentation around generated SEF or stylesheet templates.
9. Performance
  - Web Worker for SaxonJS compile/transform.
  - Prevent UI lockups on large XML.
  - Progress indicator and cancellation if possible.
10. Storage
  - LocalStorage for small projects.
  - IndexedDB for larger documents and histories.