diff --git a/.travis.yml b/.travis.yml
index 5246ea28..54116a76 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -41,9 +41,12 @@ matrix:
   - env: BUILD=cabal GHCVER=8.2.2 CABALVER=2.0 HAPPYVER=1.19.5 ALEXVER=3.1.7
     compiler: ": #GHC 8.2.2"
     addons: {apt: {packages: [cabal-install-2.0,ghc-8.2.2,happy-1.19.5,alex-3.1.7], sources: [hvr-ghc]}}
-  - env: BUILD=cabal GHCVER=8.4.3 CABALVER=2.2 HAPPYVER=1.19.5 ALEXVER=3.1.7
-    compiler: ": #GHC 8.4.3"
-    addons: {apt: {packages: [cabal-install-2.2,ghc-8.4.3,happy-1.19.5,alex-3.1.7], sources: [hvr-ghc]}}
+  - env: BUILD=cabal GHCVER=8.4.4 CABALVER=2.2 HAPPYVER=1.19.5 ALEXVER=3.1.7
+    compiler: ": #GHC 8.4.4"
+    addons: {apt: {packages: [cabal-install-2.2,ghc-8.4.4,happy-1.19.5,alex-3.1.7], sources: [hvr-ghc]}}
+  - env: BUILD=cabal GHCVER=8.6.3 CABALVER=2.4 HAPPYVER=1.19.5 ALEXVER=3.1.7
+    compiler: ": #GHC 8.6.3"
+    addons: {apt: {packages: [cabal-install-2.4,ghc-8.6.3,happy-1.19.5,alex-3.1.7], sources: [hvr-ghc]}}
 
   # Build with the newest GHC and cabal-install. This is an accepted failure,
   # see below.
@@ -61,10 +64,18 @@ matrix:
     compiler: ": #stack 8.0.2"
     addons: {apt: {packages: [libgmp-dev]}}
 
-  - env: BUILD=stack ARGS="--stack-yaml stack-lts-11.yaml --resolver lts-11"
+  - env: BUILD=stack ARGS="--resolver lts-11"
     compiler: ": #stack 8.2.2"
     addons: {apt: {packages: [libgmp-dev]}}
 
+  - env: BUILD=stack ARGS="--resolver lts-12"
+    compiler: ": #stack 8.4.4"
+    addons: {apt: {packages: [libgmp-dev]}}
+
+  - env: BUILD=stack ARGS="--resolver lts-13"
+    compiler: ": #stack 8.6.3"
+    addons: {apt: {packages: [libgmp-dev]}}
+
   - env: BUILD=stack ARGS="--stack-yaml stack-persistent-2-9.yaml"
     compiler: ": #stack/persistent 2.9"
     addons: {apt: {packages: [libgmp-dev]}}
@@ -83,10 +94,18 @@ matrix:
     compiler: ": #stack 8.0.2 osx"
     os: osx
 
-  - env: BUILD=stack ARGS="--stack-yaml stack-lts-11.yaml --resolver lts-11"
+  - env: BUILD=stack ARGS="--resolver lts-11"
     compiler: ": #stack 8.2.2 osx"
     os: osx
 
+  - env: BUILD=stack ARGS="--resolver lts-12"
+    compiler: ": #stack 8.4.4 osx"
+    os: osx
+
+  - env: BUILD=stack ARGS="--resolver lts-13"
+    compiler: ": #stack 8.6.3 osx"
+    os: osx
+
   - env: BUILD=stack ARGS="--stack-yaml stack-persistent-2-9.yaml"
     compiler: ": #stack/persistent 2.9"
     os: osx
diff --git a/appveyor.yml b/appveyor.yml
index a1ef35d1..a97d407b 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -9,7 +9,7 @@ install:
 build: off
 
 build_script:
-  - stack --no-terminal test --no-run-tests
+  - stack --no-terminal test --no-run-tests --resolver lts-11
 
 test_script:
-  - stack --jobs 1 --no-terminal test
+  - stack --jobs 1 --no-terminal test --resolver lts-11
diff --git a/stack-lts-11.yaml b/stack-lts-11.yaml
deleted file mode 120000
index 2df91e0c..00000000
--- a/stack-lts-11.yaml
+++ /dev/null
@@ -1 +0,0 @@
-stack.yaml
\ No newline at end of file
diff --git a/stack.yaml b/stack.yaml
index 5789bb4b..81f227c9 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -1,4 +1,4 @@
-resolver: lts-11.10
+resolver: lts-13.4
 packages:
 - ./yesod-core
 - ./yesod-static