diff --git a/scripts/aoc-lib.rkt b/scripts/aoc-lib.rkt
new file mode 100644
index 0000000..10f4b6f
--- /dev/null
+++ b/scripts/aoc-lib.rkt
@@ -0,0 +1,59 @@
+#lang racket
+
+(require net/uri-codec net/http-client)
+(provide aoc-fetch-input aoc-submit-answer)
+
+(define *host* "adventofcode.com")
+
+(define/contract (puzzle-path year day endpoint)
+  (-> string? string? (or/c "input" "answer") path?)
+  (build-path "/" year "day" day endpoint))
+
+(define (make-headers session)
+  (list (string-append "Cookie: session=" session)))
+
+(define (aoc-request year day endpoint session [method 'GET] [data #f])
+  (define (parse-headers hlist)
+    (for/list ([h (in-list hlist)])
+      (match h
+        [(pregexp #px"^([^:]+): (.*?)$" (list _ k v))
+         (cons (string->symbol (string-downcase (bytes->string/utf-8 k)))
+               (bytes->string/utf-8 v))]
+        [x (cons 'unknown x)])))
+
+  (define (do-request path headers)
+    (define-values [status headers-out content]
+      (http-sendrecv *host* path #:ssl? #t #:headers headers))
+    (define headers-out/parsed (parse-headers headers-out))
+
+    (match status
+      [(pregexp #px"^HTTP/1\\.[10] 200") content]
+      [(pregexp #px"^HTTP/1\\.[10] 302")
+       (define location (cdr (or (assoc 'location headers-out/parsed)
+                                 (error "got 302 with no location"))))
+       (printf "got redirect to ~a\n" location)
+       (close-input-port content)
+       (do-request location headers)]
+      [(pregexp #px"^HTTP/1\\.[10] 404")
+       (error "endpoint returned 404\n response: " (port->bytes content))]
+      [stat
+       (error "endpoint returned unexpected data\n status: " stat "\n response: "
+              (port->bytes content))]))
+  (do-request (path->string (puzzle-path year day endpoint)) (make-headers session)))
+
+(define/contract (aoc-fetch-input year day session)
+  (-> string? string? string? input-port?)
+  (aoc-request year day "input" session))
+
+(define/contract (aoc-submit-answer year day session part answer)
+  (-> string? string? string? (or/c 1 2 "1" "2") string? (or/c symbol? bytes?))
+  (define data `((level . ,(~a part))
+                 (answer . ,answer)))
+  (define resp
+    (port->bytes (aoc-request year day "answer" session 'POST (alist->form-urlencoded data))))
+
+  (match resp
+    [(pregexp #px"Both parts of this puzzle are complete") 'day-complete]
+    [(pregexp #px"That's the right answer") 'answer-correct]
+    [(pregexp #px"That's not the right answer") 'answer-incorrect]
+    [x x]))
diff --git a/scripts/get-input b/scripts/get-input
index 4ef33c2..33c4668 100755
--- a/scripts/get-input
+++ b/scripts/get-input
@@ -1,14 +1,10 @@
 #!/usr/bin/env racket
 #lang racket
 
-(require net/http-client)
-(define *year* "2020")
+(require "aoc-lib.rkt")
 
 (command-line
   #:program "get-input"
   #:args (day)
-  (define-values [status headers content]
-    (http-sendrecv "adventofcode.com" (format "/~a/day/~a/input" *year* day)
-                   #:ssl? #t
-                   #:headers (list (format "Cookie: session=~a" (getenv "AOC_SESSION")))))
-  (call-with-output-file (build-path "inputs" day) (lambda (out) (copy-port content out))))
+  (define in (aoc-fetch-input (getenv "AOC_YEAR") day (getenv "AOC_SESSION")))
+  (call-with-output-file (build-path "inputs" day) (lambda (out) (copy-port in out))))
diff --git a/scripts/make-day b/scripts/make-day
index e81d7c7..187fa40 100755
--- a/scripts/make-day
+++ b/scripts/make-day
@@ -19,7 +19,7 @@
 
 
 (command-line
-  #:program "get-input"
+  #:program "make-day"
   #:args (day)
   (call-with-output-file
     (format "~a.rkt" day)
diff --git a/scripts/submit-answer b/scripts/submit-answer
new file mode 100755
index 0000000..611abdb
--- /dev/null
+++ b/scripts/submit-answer
@@ -0,0 +1,10 @@
+#!/usr/bin/env racket
+#lang racket
+
+(require "aoc-lib.rkt")
+
+(command-line
+  #:program "submit-answer"
+  #:args (day part answer)
+  (define resp (aoc-submit-answer (getenv "AOC_YEAR") day (getenv "AOC_SESSION") part answer))
+  (printf "server returned: ~a\n" resp))