diff --git a/default.nix b/default.nix
index cc526bf34eaac576f52525637c2a524fc97f21f3..964e4af12f3c079a0af003ee1a867570aa919827 100644
--- a/default.nix
+++ b/default.nix
@@ -8,14 +8,9 @@
 let
   pkgs' = pkgs.extend (import ./overlays.nix);
   callPackage = pkgs'.python27Packages.callPackage;
-  tahoe-lafs' = (
-    if tahoe-lafs != null
-    then tahoe-lafs
-    else callPackage ./tahoe-lafs.nix { }
-  );
+  tahoe-lafs = if tahoe-lafs == null then pkgs.python2Packages.tahoe-lafs-1_14 else tahoe-lafs;
 in
 callPackage ./zkapauthorizer.nix {
   challenge-bypass-ristretto = callPackage ./python-challenge-bypass-ristretto.nix { };
-  inherit hypothesisProfile collectCoverage testSuite trialArgs;
-  tahoe-lafs = tahoe-lafs';
+  inherit hypothesisProfile collectCoverage testSuite trialArgs tahoe-lafs;
 }
diff --git a/nixpkgs.nix b/nixpkgs.nix
deleted file mode 100644
index 28889093ccc5ba3ac9feb2a099181fdea64b4dda..0000000000000000000000000000000000000000
--- a/nixpkgs.nix
+++ /dev/null
@@ -1,8 +0,0 @@
-{ pkgs ? import <nixpkgs> { } }:
-let
-  nixpkgs = pkgs.path;
-  args =
-  { overlays = [ (import ./overlays.nix) ];
-  };
-in
-pkgs.callPackage nixpkgs args
diff --git a/tahoe-lafs-repo.nix b/tahoe-lafs-repo.nix
deleted file mode 100644
index fc944e5739e7246a922761b2c7abaf05b62b8327..0000000000000000000000000000000000000000
--- a/tahoe-lafs-repo.nix
+++ /dev/null
@@ -1,9 +0,0 @@
-let
-  pkgs = import <nixpkgs> {};
-in
-  pkgs.fetchFromGitHub {
-    owner = "tahoe-lafs";
-    repo = "tahoe-lafs";
-    rev = "tahoe-lafs-1.14.0";
-    sha256 = "1ahdiapg57g6icv7p2wbzgkwl9lzdlgrsvbm5485414m7z2d6las";
-  }
diff --git a/tahoe-lafs.nix b/tahoe-lafs.nix
deleted file mode 100644
index 212439638fb54e1dfb57d5ae91784759e234d02e..0000000000000000000000000000000000000000
--- a/tahoe-lafs.nix
+++ /dev/null
@@ -1,20 +0,0 @@
-{ python2Packages }:
-let
-  # Manually assemble the tahoe-lafs build inputs because tahoe-lafs 1.14.0
-  # eliot package runs the eliot test suite which is flaky.  Doing this gives
-  # us a place to insert a `doCheck = false` (at the cost of essentially
-  # duplicating tahoe-lafs' default.nix).  Not ideal but at least we can throw
-  # it away when we upgrade to the next tahoe-lafs version.
-  repo = ((import ./tahoe-lafs-repo.nix) + "/nix");
-  nevow-drv = repo + "/nevow.nix";
-  nevow = python2Packages.callPackage nevow-drv { };
-  eliot-drv = repo + "/eliot.nix";
-  eliot = (python2Packages.callPackage eliot-drv { }).overrideAttrs (old: {
-    doInstallCheck = false;
-  });
-  tahoe-lafs-drv = repo + "/tahoe-lafs.nix";
-  tahoe-lafs = python2Packages.callPackage tahoe-lafs-drv {
-    inherit nevow eliot;
-  };
-in
-  tahoe-lafs