(define (make-alist-dto key=)

  (define (alist? dto l)
    (and (list? l)
         (or (null? l)
             (pair? (car l)))))

  (define (alist-pure? dto alist)
    #t)

  (define (alist-map dto proc alist)
    (map
     (lambda (e)
       (define key (car e))
       (define value (cdr e))
       (cons key (proc key value)))
     alist))

  (define (alist-filter dto pred alist)
    (filter
     (lambda (e)
       (pred (car e) (cdr e)))
     alist))

  (define (alist-delete dto key alist)
    (filter
     (lambda (entry)
       (not (key= (car entry) key)))
     alist))

  (define (alist-find-update dto alist key failure success)
    (define (handle-success pair)
      (define old-key (car pair))
      (define old-value (cdr pair))
      (define (update new-key new-value)
        (cond
         ((and (eq? old-key
                    new-key)
               (eq? old-value
                    new-value))
          alist)
         (else
          (let ((new-list
                 (alist-cons
                  new-key new-value
                  (alist-delete dto old-key alist))))
            new-list))))
      (define (remove)
        (alist-delete dto old-key alist))
      (success old-key old-value update remove))

    (define (handle-failure)
      (define (insert value)
        (alist-cons key value alist))
      (define (ignore)
        alist)
      (failure insert ignore))
    (cond
     ((assoc key alist key=) => handle-success)
     (else (handle-failure))))

  (define (alist-size dto alist)
    (length alist))

  (define (alist->alist dto alist)
    alist)

  (define (alist-comparator dto dictionary)
    #f)

  (make-dto
   dictionary?-id alist?
   dict-pure?-id alist-pure?
   dict-map-id alist-map
   dict-filter-id alist-filter
   dict-find-update-id alist-find-update
   dict-size-id alist-size
   dict->alist-id alist->alist
   dict-comparator-id alist-comparator))

(define alist-eqv-dto (make-alist-dto eqv?))
(define alist-equal-dto (make-alist-dto equal?))