diff --git a/.bazelrc b/.bazelrc
index 31a414241..cdaf74744 100644
--- a/.bazelrc
+++ b/.bazelrc
@@ -8,7 +8,7 @@ build --disk_cache=.bazel-cache/bazel-disk
 build --repository_cache=tmp/bazel-repo
 build --color=yes
 build --jobs=8
-
+common --compilation_mode=fastbuild
 
 # test environment does not propagate locales by default
 # some tests reads files written in UTF8, we need to propagate the correct
diff --git a/BUILD.bazel b/BUILD.bazel
index 1ff84ef69..4668b90b9 100644
--- a/BUILD.bazel
+++ b/BUILD.bazel
@@ -34,6 +34,21 @@ haskell_toolchain_library(name = "template-haskell")
 
 haskell_toolchain_library(name = "transformers")
 
+config_setting(
+    name = "release",
+    values = {"compilation_mode": "opt"},
+)
+
+config_setting(
+    name = "development",
+    values = {"compilation_mode": "fastbuild"},
+)
+
+config_setting(
+    name = "debug",
+    values = {"compilation_mode": "dbg"},
+)
+
 haskell_repl(
     name = "hie-bios",
     collect_data = False,
diff --git a/build/common.bzl b/build/common.bzl
index c1ee8517a..46c0833b3 100644
--- a/build/common.bzl
+++ b/build/common.bzl
@@ -7,8 +7,10 @@ load(
 )
 load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 
-STANDARD_GHC_WARNINGS = [
-    "-O0",
+DEVELOPMENT_GHC_FLAGS = ["-O0"]
+RELEASE_GHC_FLAGS = ["-O1"]
+
+GHC_FLAGS = [
     "-v1",
     "-j8",
     "-fdiagnostics-color=always",
@@ -25,7 +27,13 @@ STANDARD_GHC_WARNINGS = [
     "-Wno-all-missed-specialisations",
     "-Wno-star-is-type",
     "-Wno-missing-deriving-strategies",
-]
+] + select(
+    {
+        "//:release": RELEASE_GHC_FLAGS,
+        "//:development": DEVELOPMENT_GHC_FLAGS,
+        "//:debug": DEVELOPMENT_GHC_FLAGS,
+    },
+)
 
 STANDARD_EXECUTABLE_FLAGS = [
     "-threaded",
@@ -58,10 +66,10 @@ def semantic_language_library(language, name, srcs, ts_package = "", nodetypes =
         # We can't use Template Haskell to find out the location of the
         # node-types.json files, but we can pass it in as a preprocessor
         # directive.
-        compiler_flags = STANDARD_GHC_WARNINGS + [
+        compiler_flags = GHC_FLAGS + [
             '-DNODE_TYPES_PATH="../../../../$(rootpath {})"'.format(nodetypes),
         ],
-        repl_ghci_args = STANDARD_GHC_WARNINGS + [
+        repl_ghci_args = GHC_FLAGS + [
             '-DNODE_TYPES_PATH="../../../../$(rootpath {})"'.format(nodetypes),
         ],
         srcs = srcs,
diff --git a/docs/build.md b/docs/build.md
index 2398cf2e1..7bed3f51b 100644
--- a/docs/build.md
+++ b/docs/build.md
@@ -20,8 +20,9 @@ The first time you run `bazel build`, it'll take some time, as Bazel will compil
 | Build `TARGET` library    | `cabal build TARGET:lib`            | `bazel build //TARGET`             |
 | Build semantic executable | `cabal build semantic:exe:semantic` | `bazel build //semantic:exe`       |
 | Build/run executable      | `cabal run semantic -- ARGS`        | `bazel run //semantic:exe -- ARGS` |
-| Load REPL component       | `script/ghci` and `:load`           | `bazel build //TARGET@repl`    |
+| Load REPL component       | `script/ghci` and `:load`           | `bazel build //TARGET@repl`        |
 | Run tests                 | `cabal test all`                    | `bazel test //...`                 |
+| Build with optimizations  | `cabal build --flags="+release"`    | `bazel build -copt //...`          |
 
 ## Adding a new dependency
 
@@ -53,7 +54,7 @@ The default `.bazelrc` file imports a `.bazelrc.local` file if it's present; use
 
 ## Shared variables
 
-* `STANDARD_GHC_WARNINGS`: the standard set of Cabal flags that all targets should use.
+* `GHC_FLAGS`: the standard set of Cabal flags that all targets should use.
 * `STANDARD_EXECUTABLE_FLAGS`: ditto, but with executable-specific flags.
 
 ## Custom rules
diff --git a/semantic-analysis/BUILD.bazel b/semantic-analysis/BUILD.bazel
index b97003be6..5c1c730ec 100644
--- a/semantic-analysis/BUILD.bazel
+++ b/semantic-analysis/BUILD.bazel
@@ -14,13 +14,13 @@ load(
 )
 load(
     "//:build/common.bzl",
-    "STANDARD_GHC_WARNINGS",
+    "GHC_FLAGS",
 )
 
 haskell_library(
     name = "semantic-analysis",
     srcs = glob(["src/**/*.hs"]),
-    compiler_flags = STANDARD_GHC_WARNINGS + ["-XOverloadedStrings"],
+    compiler_flags = GHC_FLAGS + ["-XOverloadedStrings"],
     deps = [
         "//:base",
         "//:containers",
diff --git a/semantic-ast/BUILD.bazel b/semantic-ast/BUILD.bazel
index 07db912d6..135bcf1c0 100644
--- a/semantic-ast/BUILD.bazel
+++ b/semantic-ast/BUILD.bazel
@@ -14,13 +14,13 @@ load(
 )
 load(
     "//:build/common.bzl",
-    "STANDARD_GHC_WARNINGS",
+    "GHC_FLAGS",
 )
 
 haskell_library(
     name = "semantic-ast",
     srcs = glob(["src/**/*.hs"]),
-    compiler_flags = STANDARD_GHC_WARNINGS + ["-XOverloadedStrings"],
+    compiler_flags = GHC_FLAGS + ["-XOverloadedStrings"],
     deps = [
         "//:base",
         "//:bytestring",
diff --git a/semantic-codeql/BUILD.bazel b/semantic-codeql/BUILD.bazel
index 6e6f284ae..54631fb81 100644
--- a/semantic-codeql/BUILD.bazel
+++ b/semantic-codeql/BUILD.bazel
@@ -14,5 +14,6 @@ semantic_language_library(
 
 semantic_language_parsing_test(
     language = "codeql",
-    project = "ql",
+    semantic_package = "ql",
+    ts_package = "ql",
 )
diff --git a/semantic-core/BUILD.bazel b/semantic-core/BUILD.bazel
index 8bb4b1757..9cf24f642 100644
--- a/semantic-core/BUILD.bazel
+++ b/semantic-core/BUILD.bazel
@@ -14,14 +14,14 @@ load(
 )
 load(
     "//:build/common.bzl",
+    "GHC_FLAGS",
     "STANDARD_EXECUTABLE_FLAGS",
-    "STANDARD_GHC_WARNINGS",
 )
 
 haskell_library(
     name = "semantic-core",
     srcs = glob(["src/**/*.hs"]),
-    compiler_flags = STANDARD_GHC_WARNINGS,
+    compiler_flags = GHC_FLAGS,
     deps = [
         "//:base",
         "//:text",
@@ -45,7 +45,7 @@ haskell_test(
         "test/*.hs",
         "test/Source/Test.hs",
     ]),
-    compiler_flags = STANDARD_GHC_WARNINGS + STANDARD_EXECUTABLE_FLAGS,
+    compiler_flags = GHC_FLAGS + STANDARD_EXECUTABLE_FLAGS,
     deps = [
         "//:base",
         "//:text",
diff --git a/semantic-parse/BUILD.bazel b/semantic-parse/BUILD.bazel
index 4698e9fb8..171a5890a 100644
--- a/semantic-parse/BUILD.bazel
+++ b/semantic-parse/BUILD.bazel
@@ -8,7 +8,7 @@ load(
 )
 load(
     "//:build/common.bzl",
-    "STANDARD_GHC_WARNINGS",
+    "GHC_FLAGS",
 )
 
 # Doesn't build right now.
@@ -16,7 +16,7 @@ load(
 haskell_binary(
     name = "exe",
     srcs = ["app/Main.hs"],
-    compiler_flags = STANDARD_GHC_WARNINGS,
+    compiler_flags = GHC_FLAGS,
     deps = [
         "//:base",
         "//:bytestring",
diff --git a/semantic-scope-graph/BUILD.bazel b/semantic-scope-graph/BUILD.bazel
index 66ef5c5d3..c9c18de70 100644
--- a/semantic-scope-graph/BUILD.bazel
+++ b/semantic-scope-graph/BUILD.bazel
@@ -14,13 +14,13 @@ load(
 )
 load(
     "//:build/common.bzl",
-    "STANDARD_GHC_WARNINGS",
+    "GHC_FLAGS",
 )
 
 haskell_library(
     name = "semantic-scope-graph",
     srcs = glob(["src/**/*.hs"]),
-    compiler_flags = STANDARD_GHC_WARNINGS + ["-XOverloadedStrings"],
+    compiler_flags = GHC_FLAGS + ["-XOverloadedStrings"],
     deps = [
         "//:base",
         "//:containers",
diff --git a/semantic-source/BUILD.bazel b/semantic-source/BUILD.bazel
index 2c366fcc4..a4d108656 100644
--- a/semantic-source/BUILD.bazel
+++ b/semantic-source/BUILD.bazel
@@ -14,14 +14,14 @@ load(
 )
 load(
     "//:build/common.bzl",
+    "GHC_FLAGS",
     "STANDARD_EXECUTABLE_FLAGS",
-    "STANDARD_GHC_WARNINGS",
 )
 
 haskell_library(
     name = "semantic-source",
     srcs = glob(["src/**/*.hs"]),
-    compiler_flags = STANDARD_GHC_WARNINGS + ["-XOverloadedStrings"],
+    compiler_flags = GHC_FLAGS + ["-XOverloadedStrings"],
     deps = [
         "//:base",
         "//:bytestring",
@@ -44,7 +44,7 @@ haskell_test(
         "test/Source/Test.hs",
         "test/Test.hs",
     ],
-    compiler_flags = STANDARD_GHC_WARNINGS + STANDARD_EXECUTABLE_FLAGS,
+    compiler_flags = GHC_FLAGS + STANDARD_EXECUTABLE_FLAGS,
     deps = [
         ":semantic-source",
         "//:base",
diff --git a/semantic-tags/BUILD.bazel b/semantic-tags/BUILD.bazel
index 17b4c4a85..003f6527b 100644
--- a/semantic-tags/BUILD.bazel
+++ b/semantic-tags/BUILD.bazel
@@ -14,13 +14,13 @@ load(
 )
 load(
     "//:build/common.bzl",
-    "STANDARD_GHC_WARNINGS",
+    "GHC_FLAGS",
 )
 
 haskell_library(
     name = "semantic-tags",
     srcs = glob(["src/**/*.hs"]),
-    compiler_flags = STANDARD_GHC_WARNINGS,
+    compiler_flags = GHC_FLAGS,
     deps = [
         "//:base",
         "//:text",
diff --git a/semantic/BUILD.bazel b/semantic/BUILD.bazel
index f2233da76..3fffa0cb6 100644
--- a/semantic/BUILD.bazel
+++ b/semantic/BUILD.bazel
@@ -16,8 +16,8 @@ load(
 )
 load(
     "//:build/common.bzl",
+    "GHC_FLAGS",
     "STANDARD_EXECUTABLE_FLAGS",
-    "STANDARD_GHC_WARNINGS",
 )
 load(
     "//:build/example_repos.bzl",
@@ -55,7 +55,7 @@ semantic_common_dependencies = [
 haskell_library(
     name = "semantic",
     srcs = glob(["src/**/*.hs"]),
-    compiler_flags = STANDARD_GHC_WARNINGS + ["-XStrictData"],
+    compiler_flags = GHC_FLAGS + ["-XStrictData"],
     version = "0.11.0.0",
     deps = semantic_common_dependencies + [
         "//:base",
@@ -110,7 +110,7 @@ haskell_library(
 haskell_binary(
     name = "exe",
     srcs = glob(["app/**/*.hs"]),
-    compiler_flags = STANDARD_GHC_WARNINGS + STANDARD_EXECUTABLE_FLAGS + ["-XStrictData"],
+    compiler_flags = GHC_FLAGS + STANDARD_EXECUTABLE_FLAGS + ["-XStrictData"],
     deps = [
         ":semantic",
         "//:base",
@@ -142,7 +142,7 @@ haskell_test(
             "test/System/Path/Fixture.hs",
         ],
     ),
-    compiler_flags = STANDARD_GHC_WARNINGS + STANDARD_EXECUTABLE_FLAGS + [
+    compiler_flags = GHC_FLAGS + STANDARD_EXECUTABLE_FLAGS + [
         "-XStrictData",
     ],
     data = glob(include = [
@@ -186,7 +186,7 @@ haskell_test(
     srcs = [
         "test/Examples.hs",
     ],
-    compiler_flags = STANDARD_GHC_WARNINGS + STANDARD_EXECUTABLE_FLAGS + [
+    compiler_flags = GHC_FLAGS + STANDARD_EXECUTABLE_FLAGS + [
         "-XStrictData",
     ],
     data = glob(include = [