please don't pencilmark the entire grid

Solve Puzzle

Rules

• Normal sudoku rules apply.
  Every row, column, and 3 × 3 box contains all digits 1-9.
• Killer rule applies.
  Digits in a cage sum to the number written in the corner of the cage. Digits may not repeat in a cage.
• Thermo rule applies.
  Along a thermometer, digits strictly increase from bulb to end.