diff --git a/Makefile.config.in b/Makefile.config.in
index 6948dad5..3cae30d4 100644
--- a/Makefile.config.in
+++ b/Makefile.config.in
@@ -5,6 +5,7 @@ CXX = @CXX@
 CXXFLAGS = @CXXFLAGS@
 ENABLE_S3 = @ENABLE_S3@
 HAVE_SODIUM = @HAVE_SODIUM@
+HAVE_READLINE = @HAVE_READLINE@
 LIBCURL_LIBS = @LIBCURL_LIBS@
 OPENSSL_LIBS = @OPENSSL_LIBS@
 PACKAGE_NAME = @PACKAGE_NAME@
diff --git a/configure.ac b/configure.ac
index c7026cf9..ac37456a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -196,6 +196,14 @@ if test "$gc" = yes; then
 fi
 
 
+# Check for readline, needed by "nix repl".
+AX_LIB_READLINE
+if test "$ax_cv_lib_readline" != "no"; then
+  have_readline=1
+fi
+AC_SUBST(HAVE_READLINE, [$have_readline])
+
+
 AC_ARG_ENABLE(init-state, AC_HELP_STRING([--disable-init-state],
   [do not initialise DB etc. in `make install']),
   init_state=$enableval, init_state=yes)
diff --git a/nix.spec.in b/nix.spec.in
index 390893d6..3ba2dfc9 100644
--- a/nix.spec.in
+++ b/nix.spec.in
@@ -20,9 +20,11 @@ Requires: curl
 Requires: bzip2
 Requires: gzip
 Requires: xz
+Requires: readline
 BuildRequires: bzip2-devel
 BuildRequires: sqlite-devel
 BuildRequires: libcurl-devel
+BuildRequires: readline-devel
 
 # Hack to make that shitty RPM scanning hack shut up.
 Provides: perl(Nix::SSH)
diff --git a/release.nix b/release.nix
index 534c218c..7adc8738 100644
--- a/release.nix
+++ b/release.nix
@@ -299,7 +299,7 @@ let
       src = jobs.tarball;
       diskImage = (diskImageFun vmTools.diskImageFuns)
         { extraPackages =
-            [ "sqlite" "sqlite-devel" "bzip2-devel" "emacs" "libcurl-devel" "openssl-devel" "xz-devel" ]
+            [ "sqlite" "sqlite-devel" "bzip2-devel" "emacs" "libcurl-devel" "openssl-devel" "xz-devel" "readline-devel" ]
             ++ extraPackages; };
       memSize = 1024;
       meta.schedulingPriority = 50;
@@ -321,14 +321,14 @@ let
       src = jobs.tarball;
       diskImage = (diskImageFun vmTools.diskImageFuns)
         { extraPackages =
-            [ "libsqlite3-dev" "libbz2-dev" "libcurl-dev" "libcurl3-nss" "libssl-dev" "liblzma-dev" ]
+            [ "libsqlite3-dev" "libbz2-dev" "libcurl-dev" "libcurl3-nss" "libssl-dev" "liblzma-dev" "libreadline-dev" ]
             ++ extraPackages; };
       memSize = 1024;
       meta.schedulingPriority = 50;
       postInstall = "make installcheck";
       configureFlags = "--sysconfdir=/etc";
       debRequires =
-        [ "curl" "libsqlite3-0" "libbz2-1.0" "bzip2" "xz-utils" "libssl1.0.0" "liblzma5" ]
+        [ "curl" "libsqlite3-0" "libbz2-1.0" "bzip2" "xz-utils" "libssl1.0.0" "liblzma5" "libreadline6" ]
         ++ extraDebPackages;
       debMaintainer = "Eelco Dolstra <eelco.dolstra@logicblox.com>";
       doInstallCheck = true;
diff --git a/shell.nix b/shell.nix
index 37a936fd..bbce6856 100644
--- a/shell.nix
+++ b/shell.nix
@@ -35,7 +35,7 @@ with import <nixpkgs> {};
   shellHook =
     ''
       export prefix=$(pwd)/inst
-      configureFlags+=" --prefix=prefix"
+      configureFlags+=" --prefix=$prefix"
       PKG_CONFIG_PATH=$prefix/lib/pkgconfig:$PKG_CONFIG_PATH
       PATH=$prefix/bin:$PATH
     '';
diff --git a/src/nix/local.mk b/src/nix/local.mk
index 21f190e4..e71cf16f 100644
--- a/src/nix/local.mk
+++ b/src/nix/local.mk
@@ -6,6 +6,8 @@ nix_SOURCES := $(wildcard $(d)/*.cc)
 
 nix_LIBS = libexpr libmain libstore libutil libformat
 
-nix_LDFLAGS = -lreadline
+ifeq ($(HAVE_READLINE), 1)
+  nix_LDFLAGS += -lreadline
+endif
 
 $(eval $(call install-symlink, nix, $(bindir)/nix-hash))
diff --git a/src/nix/repl.cc b/src/nix/repl.cc
index 17203d3c..13488bf1 100644
--- a/src/nix/repl.cc
+++ b/src/nix/repl.cc
@@ -1,3 +1,5 @@
+#if HAVE_LIBREADLINE
+
 #include <iostream>
 #include <cstdlib>
 
@@ -726,3 +728,5 @@ struct CmdRepl : StoreCommand
 static RegisterCommand r1(make_ref<CmdRepl>());
 
 }
+
+#endif