diff --git a/rosette/private/install.rkt b/rosette/private/install.rkt
index 5ae12314..4709ab39 100644
--- a/rosette/private/install.rkt
+++ b/rosette/private/install.rkt
@@ -20,7 +20,7 @@
 ; far more obvious.
 (define z3-install-failure #f)
 
-(define z3-version "4.8.8")
+(define z3-version "4.12.6")
 
 (define (print-failure path msg)
   (printf "\n\n********** Failed to install Z3 **********\n\n")
@@ -66,19 +66,17 @@
          (not (equal? (resolve-path p) p)))))
 
 (define (get-z3-url)
-  ; TODO: Z3 packages a macOS aarch64 binary as of 4.8.16, so remove this special case when we update
-  ; to a newer Z3 version.
-  (if (and (equal? (system-type 'os*) 'macosx) (equal? (system-type 'arch) 'aarch64))
-      (values "https://github.com/emina/rosette/releases/download/4.1/z3-4.8.8-aarch64-osx-13.3.1.zip" "z3")
-      (let ()
-        (define site "https://github.com/Z3Prover/z3/releases/download")
-        (define-values (os exe)
-          (match (list (system-type 'os*) (system-type 'arch))
-            ['(linux x86_64)   (values "x64-ubuntu-16.04" "z3")]
-            [`(macosx ,_)      (values "x64-osx-10.14.6" "z3")]
-            ['(windows x86_64) (values "x64-win" "z3.exe")]
-            [any               (raise-user-error 'get-z3-url "No Z3 binary available for system type '~a" any)]))
-        (define name (format "z3-~a-~a" z3-version os))
-        (values
-         (format "~a/z3-~a/~a.zip" site z3-version name)
-         (format "~a/bin/~a" name exe)))))
+  (define site "https://github.com/Z3Prover/z3/releases/download")
+  (define-values (os exe)
+    (match (list (system-type 'os*) (system-type 'arch))
+      ['(linux x86_64)    (values "x64-glibc-2.35" "z3")]
+      ['(linux aarch64)   (values "arm64-glibc-2.35" "z3")]
+      ['(macosx x86_64)   (values "x64-osx-11.7.10" "z3")]
+      ['(macosx aarch64)  (values "arm64-osx-11.0" "z3")]
+      ['(windows x86_64)  (values "x64-win" "z3.exe")]
+      ['(windows aarch64) (values "arm64-win" "z3.exe")]
+      [any               (raise-user-error 'get-z3-url "No Z3 binary available for system type '~a" any)]))
+  (define name (format "z3-~a-~a" z3-version os))
+  (values
+   (format "~a/z3-~a/~a.zip" site z3-version name)
+   (format "~a/bin/~a" name exe)))
diff --git a/rosette/solver/smt/dec.rkt b/rosette/solver/smt/dec.rkt
index 408d0c58..753f1232 100644
--- a/rosette/solver/smt/dec.rkt
+++ b/rosette/solver/smt/dec.rkt
@@ -14,7 +14,7 @@
                   @bvslt @bvsle @bvult @bvule   
                   @bvnot @bvor @bvand @bvxor @bvshl @bvlshr @bvashr
                   @bvneg @bvadd @bvmul @bvudiv @bvsdiv @bvurem @bvsrem @bvsmod
-                  @concat @extract))
+                  @concat @extract @sign-extend @zero-extend @integer->bitvector))
 
 
 (provide decode-model)
@@ -131,6 +131,12 @@
         (bv n (bitvector len))]
        [(list (list (== '_) (== 'extract) i j) s)
         `(, @extract ,(inline i sol ~env) ,(inline j sol ~env) ,(inline s sol ~env))]
+       [(list (list (== '_) (== 'sign_extend) i) s)
+        `(, @sign-extend ,(inline s sol ~env) ,(bitvector (inline i sol ~env)))]
+       [(list (list (== '_) (== 'zero_extend) i) s)
+        `(, @zero-extend ,(inline s sol ~env) ,(bitvector (inline i sol ~env)))]
+       [(list (list (== '_) (== 'int2bv) i) s)
+        `(, @integer->bitvector ,(inline s sol ~env) ,(bitvector (inline i sol ~env)))]
        [(list (== 'let) binds body)
         (substitute (inline body sol ~env)
                     (for/hash ([id:expr binds])
diff --git a/test/query/solve.rkt b/test/query/solve.rkt
index 52453739..77c995ff 100644
--- a/test/query/solve.rkt
+++ b/test/query/solve.rkt
@@ -65,8 +65,9 @@
       (check-pred
        unknown?
        (solve
-        (begin (assert (> (* xi xi) 3))
-               (assert (= (+ (* xr xr xr) (* xr yr)) 3.0))))))))
+        (assert (forall (list xi)
+                        (exists (list xr)
+                                (= yi (* (- xi xr) (- xi xr)))))))))))
      
 (define regression-tests 
   (test-suite+ "Solve regression tests."