diff --git a/Cargo.lock b/Cargo.lock
index ee1faed0..d4ab32c4 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -42,12 +42,53 @@ dependencies = [
 ]
 
 [[package]]
-name = "ansi_term"
-version = "0.12.1"
+name = "anstream"
+version = "0.6.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d52a9bb7ec0cf484c551830a7ce27bd20d67eac647e1befb56b0be4ee39a55d2"
+checksum = "43d5b281e737544384e969a5ccad3f1cdd24b48086a0fc1b2a5262a26b8f4f4a"
 dependencies = [
- "winapi 0.3.9",
+ "anstyle",
+ "anstyle-parse",
+ "anstyle-query",
+ "anstyle-wincon",
+ "colorchoice",
+ "is_terminal_polyfill",
+ "utf8parse",
+]
+
+[[package]]
+name = "anstyle"
+version = "1.0.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "940b3a0ca603d1eade50a4846a2afffd5ef57a9feac2c0e2ec2e14f9ead76000"
+
+[[package]]
+name = "anstyle-parse"
+version = "0.2.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4e7644824f0aa2c7b9384579234ef10eb7efb6a0deb83f9630a49594dd9c15c2"
+dependencies = [
+ "utf8parse",
+]
+
+[[package]]
+name = "anstyle-query"
+version = "1.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "40c48f72fd53cd289104fc64099abca73db4166ad86ea0b4341abe65af83dadc"
+dependencies = [
+ "windows-sys 0.61.2",
+]
+
+[[package]]
+name = "anstyle-wincon"
+version = "3.0.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "291e6a250ff86cd4a820112fb8898808a366d8f9f58ce16d1f538353ad55747d"
+dependencies = [
+ "anstyle",
+ "once_cell_polyfill",
+ "windows-sys 0.61.2",
 ]
 
 [[package]]
@@ -96,7 +137,7 @@ checksum = "9035ad2d096bed7955a320ee7e2230574d28fd3c3a0f186cbea1ff3c7eed5dbb"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -154,7 +195,7 @@ dependencies = [
  "regex",
  "rustc-hash",
  "shlex",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -394,19 +435,44 @@ dependencies = [
 
 [[package]]
 name = "clap"
-version = "2.34.0"
+version = "4.5.60"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a0610544180c38b88101fecf2dd634b174a62eef6946f84dfc6a7127512b381c"
+checksum = "2797f34da339ce31042b27d23607e051786132987f595b02ba4f6a6dffb7030a"
 dependencies = [
- "ansi_term",
- "atty",
- "bitflags 1.3.2",
- "strsim 0.8.0",
- "textwrap",
- "unicode-width 0.1.14",
- "vec_map",
+ "clap_builder",
+ "clap_derive",
+]
+
+[[package]]
+name = "clap_builder"
+version = "4.5.60"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "24a241312cea5059b13574bb9b3861cabf758b879c15190b37b6d6fd63ab6876"
+dependencies = [
+ "anstream",
+ "anstyle",
+ "clap_lex",
+ "strsim",
+]
+
+[[package]]
+name = "clap_derive"
+version = "4.5.55"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a92793da1a46a5f2a02a6f4c46c6496b28c43638adea8306fcb0caa1634f24e5"
+dependencies = [
+ "heck",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
+[[package]]
+name = "clap_lex"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c8d4a3bb8b1e0c1050499d1815f5ab16d04f0959b233085fb31653fbfc9d98f9"
+
 [[package]]
 name = "cobs"
 version = "0.3.0"
@@ -416,6 +482,12 @@ dependencies = [
  "thiserror 2.0.18",
 ]
 
+[[package]]
+name = "colorchoice"
+version = "1.0.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d07550c9036bf2ae0c684c4297d503f838287c83c53686d05370d0e139ae570"
+
 [[package]]
 name = "constant_time_eq"
 version = "0.1.5"
@@ -544,7 +616,7 @@ dependencies = [
  "cranelift-assembler-x64-meta",
  "cranelift-codegen-shared",
  "cranelift-srcgen",
- "heck 0.5.0",
+ "heck",
  "pulley-interpreter",
 ]
 
@@ -684,7 +756,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "13b588ba4ac1a99f7f2964d24b3d896ddc6bf847ee3855dbd4366f058cfcd331"
 dependencies = [
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -734,8 +806,8 @@ dependencies = [
  "ident_case",
  "proc-macro2",
  "quote",
- "strsim 0.11.1",
- "syn 2.0.109",
+ "strsim",
+ "syn",
 ]
 
 [[package]]
@@ -746,7 +818,7 @@ checksum = "fc34b93ccb385b40dc71c6fceac4b2ad23662c7eeb248cf10d529b7e055b6ead"
 dependencies = [
  "darling_core",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -796,7 +868,7 @@ dependencies = [
  "darling",
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -806,7 +878,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ab63b0e2bf4d5928aff72e83a7dace85d7bba5fe12dcc3c5a572d78caffd3f3c"
 dependencies = [
  "derive_builder_core",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -826,7 +898,7 @@ checksum = "bda628edc44c4bb645fbe0f758797143e4e07926f7ebf4e9bdfbd3d2ce621df3"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -909,7 +981,7 @@ checksum = "97369cbbc041bc366949bc74d34658d6cda5621039731c6310521892a3a20ae0"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -1245,7 +1317,7 @@ version = "0.2.24"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cfe4fbac503b8d1f88e6676011885f34b7174f46e59956bba534ba83abded4df"
 dependencies = [
- "unicode-width 0.2.2",
+ "unicode-width",
 ]
 
 [[package]]
@@ -1351,15 +1423,6 @@ dependencies = [
  "serde_core",
 ]
 
-[[package]]
-name = "heck"
-version = "0.3.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6d621efb26863f0e9924c6ac577e8275e5e6b77455db64ffa6c65c904e9e132c"
-dependencies = [
- "unicode-segmentation",
-]
-
 [[package]]
 name = "heck"
 version = "0.5.0"
@@ -1690,6 +1753,12 @@ version = "2.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "469fb0b9cefa57e3ef31275ee7cacb78f2fdca44e4765491884a2b119d4eb130"
 
+[[package]]
+name = "is_terminal_polyfill"
+version = "1.70.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a6cb138bb79a146c1bd460005623e142ef0181e3d0219cb493e02f7d08a35695"
+
 [[package]]
 name = "itertools"
 version = "0.10.5"
@@ -1928,7 +1997,7 @@ checksum = "ac84fd3f360fcc43dc5f5d186f02a94192761a080e8bc58621ad4d12296a58cf"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -2150,6 +2219,12 @@ version = "1.21.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "42f5e15c9953c5e4ccceeb2e7382a716482c34515315f7b03532b8b4e8393d2d"
 
+[[package]]
+name = "once_cell_polyfill"
+version = "1.70.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "384b8ab6d37215f3c5301a95a4accb5d64aa607f1fcb26a11b5303878451b4fe"
+
 [[package]]
 name = "opener"
 version = "0.7.2"
@@ -2185,7 +2260,7 @@ checksum = "a948666b637a0f465e8564c73e89d4dde00d72d4d473cc972f390fc3dcee7d9c"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -2316,7 +2391,7 @@ dependencies = [
  "phf_shared",
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -2478,31 +2553,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "479ca8adacdd7ce8f1fb39ce9ecccbfe93a3f1344b3d0d97f20bc0196208f62b"
 dependencies = [
  "proc-macro2",
- "syn 2.0.109",
-]
-
-[[package]]
-name = "proc-macro-error"
-version = "1.0.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "da25490ff9892aab3fcf7c36f08cfb902dd3e71ca0f9f9517bea02a73a5ce38c"
-dependencies = [
- "proc-macro-error-attr",
- "proc-macro2",
- "quote",
- "syn 1.0.109",
- "version_check",
-]
-
-[[package]]
-name = "proc-macro-error-attr"
-version = "1.0.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a1be40180e52ecc98ad80b184934baf3d0d29f979574e439af5a55274b35f869"
-dependencies = [
- "proc-macro2",
- "quote",
- "version_check",
+ "syn",
 ]
 
 [[package]]
@@ -2534,7 +2585,7 @@ checksum = "36f7d5ef31ebf1b46cd7e722ffef934e670d7e462f49aa01cde07b9b76dca580"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -2979,7 +3030,7 @@ checksum = "d540f220d3187173da220f885ab66608367b6574e925011a9353e4badda91d79"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -3104,6 +3155,7 @@ version = "0.1.0"
 dependencies = [
  "anyhow",
  "assert_cmd",
+ "clap",
  "csv",
  "env_logger 0.8.4",
  "libloading 0.9.0",
@@ -3122,7 +3174,6 @@ dependencies = [
  "sightglass-fingerprint",
  "sightglass-recorder",
  "sightglass-upload",
- "structopt",
  "tempfile",
  "thiserror 1.0.69",
  "vega_lite_4",
@@ -3286,42 +3337,12 @@ dependencies = [
  "quote",
 ]
 
-[[package]]
-name = "strsim"
-version = "0.8.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
-
 [[package]]
 name = "strsim"
 version = "0.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
 
-[[package]]
-name = "structopt"
-version = "0.3.26"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0c6b5c64445ba8094a6ab0c3cd2ad323e07171012d9c98b0b15651daf1787a10"
-dependencies = [
- "clap",
- "lazy_static",
- "structopt-derive",
-]
-
-[[package]]
-name = "structopt-derive"
-version = "0.4.18"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dcb5ae327f9cc13b68763b5749770cb9e048a99bd9dfdfa58d0cf05d5f64afe0"
-dependencies = [
- "heck 0.3.3",
- "proc-macro-error",
- "proc-macro2",
- "quote",
- "syn 1.0.109",
-]
-
 [[package]]
 name = "strum"
 version = "0.28.0"
@@ -3337,10 +3358,10 @@ version = "0.28.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ab85eea0270ee17587ed4156089e10b9e6880ee688791d45a905f5b1ca36f664"
 dependencies = [
- "heck 0.5.0",
+ "heck",
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -3349,17 +3370,6 @@ version = "2.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "13c2bddecc57b384dee18652358fb23172facb8a2c51ccc10d74c157bdea3292"
 
-[[package]]
-name = "syn"
-version = "1.0.109"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "72b64191b275b66ffe2469e8af2c1cfe3bafa67b529ead792a6d0160888b4237"
-dependencies = [
- "proc-macro2",
- "quote",
- "unicode-ident",
-]
-
 [[package]]
 name = "syn"
 version = "2.0.109"
@@ -3385,7 +3395,7 @@ checksum = "728a70f3dbaf5bab7f0c4b1ac8d7ae5ea60a4b5549c8a5914361c99147a709d2"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -3496,15 +3506,6 @@ version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8f50febec83f5ee1df3015341d8bd429f2d1cc62bcba7ea2076759d315084683"
 
-[[package]]
-name = "textwrap"
-version = "0.11.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d326610f408c7a4eb6f51c37c330e496b08506c9457c9d34287ecc38809fb060"
-dependencies = [
- "unicode-width 0.1.14",
-]
-
 [[package]]
 name = "thiserror"
 version = "1.0.69"
@@ -3531,7 +3532,7 @@ checksum = "4fee6c4efc90059e10f81e6d42c60a18f76588c3d74cb83a0b242a2b6c7504c1"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -3542,7 +3543,7 @@ checksum = "ebc4ee7f67670e9b64d05fa4253e753e016c6c95ff35b89b7941d6b856dec1d5"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -3687,7 +3688,7 @@ checksum = "7490cfa5ec963746568740651ac6781f701c9c5ea257c58e057f3ba8cf69e8da"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -3717,18 +3718,6 @@ version = "1.0.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9312f7c4f6ff9069b165498234ce8be658059c6728633667c526e27dc2cf1df5"
 
-[[package]]
-name = "unicode-segmentation"
-version = "1.12.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f6ccf251212114b54433ec949fd6a7841275f9ada20dddd2f29e9ceea4501493"
-
-[[package]]
-name = "unicode-width"
-version = "0.1.14"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7dd6e30e90baa6f72411720665d41d89b9a3d039dc45b8faea1ddd07f617f6af"
-
 [[package]]
 name = "unicode-width"
 version = "0.2.2"
@@ -3771,6 +3760,12 @@ version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b6c140620e7ffbb22c2dee59cafe6084a59b5ffc27a8859a5f0d494b5d52b6be"
 
+[[package]]
+name = "utf8parse"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "06abde3611657adf66d383f00b093d7faecc7fa57071cce2578660c9f1010821"
+
 [[package]]
 name = "uuid"
 version = "1.23.2"
@@ -3802,12 +3797,6 @@ version = "0.2.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "accd4ea62f7bb7a82fe23066fb0957d48ef677f6eeb8215f372f52e48bb32426"
 
-[[package]]
-name = "vec_map"
-version = "0.8.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f1bddf1187be692e79c5ffeab891132dfb0f236ed36a43c7ed39f1165ee20191"
-
 [[package]]
 name = "vega_lite_4"
 version = "0.8.1"
@@ -3922,7 +3911,7 @@ dependencies = [
  "bumpalo",
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
  "wasm-bindgen-shared",
 ]
 
@@ -3942,7 +3931,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5fd23d12cc95c451c1306db5bc63075fbebb612bb70c53b4237b1ce5bc178343"
 dependencies = [
  "anyhow",
- "heck 0.5.0",
+ "heck",
  "im-rc",
  "indexmap",
  "log",
@@ -4181,7 +4170,7 @@ dependencies = [
  "anyhow",
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
  "wasmtime-internal-component-util",
  "wasmtime-internal-wit-bindgen",
  "wit-parser",
@@ -4292,7 +4281,7 @@ checksum = "737c4d956fc3a848541a064afb683dd2771132a6b125be5baaf95c4379aa47df"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -4320,7 +4309,7 @@ checksum = "2192a77a00b9a67800c2b4e1c70fb6abca79d6b529e53a2ef9dcdcc36090330d"
 dependencies = [
  "anyhow",
  "bitflags 2.10.0",
- "heck 0.5.0",
+ "heck",
  "indexmap",
  "wit-parser",
 ]
@@ -4386,7 +4375,7 @@ dependencies = [
  "bumpalo",
  "leb128fmt",
  "memchr",
- "unicode-width 0.2.2",
+ "unicode-width",
  "wasm-encoder 0.251.0",
 ]
 
@@ -4441,10 +4430,10 @@ version = "43.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4bd7a197903e5b4ff5e13aef9c891960d71e92073600ecf4c86c7e795ac1c803"
 dependencies = [
- "heck 0.5.0",
+ "heck",
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
  "wasmtime-environ",
  "witx",
 ]
@@ -4457,7 +4446,7 @@ checksum = "6410b86fcec207070d9372b215d3470bad67215e6bbac46981a16999c4abbc28"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
  "wiggle-generate",
 ]
 
@@ -4544,7 +4533,7 @@ checksum = "053e2e040ab57b9dc951b72c264860db7eb3b0200ba345b4e4c3b14f67855ddf"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -4555,7 +4544,7 @@ checksum = "3f316c4a2570ba26bbec722032c4099d8c8bc095efccdc15688708623367e358"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -4917,7 +4906,7 @@ checksum = "b659052874eb698efe5b9e8cf382204678a0086ebf46982b79d6ca3182927e5d"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
  "synstructure",
 ]
 
@@ -4938,7 +4927,7 @@ checksum = "88d2b8d9c68ad2b9e4340d7832716a4d21a22a1154777ad56ea55c51a9cf3831"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
@@ -4958,7 +4947,7 @@ checksum = "d71e5d6e06ab090c67b5e44993ec16b72dcbaabc526db883a360057678b48502"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
  "synstructure",
 ]
 
@@ -4992,7 +4981,7 @@ checksum = "eadce39539ca5cb3985590102671f2567e659fca9666581ad3411d59207951f3"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.109",
+ "syn",
 ]
 
 [[package]]
diff --git a/crates/cli/Cargo.toml b/crates/cli/Cargo.toml
index 69e95cea..a30d5859 100644
--- a/crates/cli/Cargo.toml
+++ b/crates/cli/Cargo.toml
@@ -21,7 +21,7 @@ sightglass-data = { path = "../data" }
 sightglass-fingerprint = { path = "../fingerprint" }
 sightglass-recorder = { path = "../recorder" }
 sightglass-upload = { path = "../upload" }
-structopt = { version = "0.3", features = ["color", "suggestions"] }
+clap = { version = "4", features = ["derive"] }
 thiserror = "1.0"
 rand = { version = "0.7.3", features = ["small_rng"] }
 csv = "1.1.6"
diff --git a/crates/cli/src/benchmark.rs b/crates/cli/src/benchmark.rs
index 92d5fcf7..fd6022d3 100644
--- a/crates/cli/src/benchmark.rs
+++ b/crates/cli/src/benchmark.rs
@@ -1,5 +1,6 @@
 use crate::suite::BenchmarkOrSuite;
 use anyhow::{anyhow, Context, Result};
+use clap::Parser;
 use rand::{rngs::SmallRng, Rng, SeedableRng};
 use sightglass_data::{Format, Measurement, Phase};
 use sightglass_recorder::bench_api::Engine;
@@ -13,7 +14,6 @@ use std::{
     path::{Path, PathBuf},
     process::{Command, Stdio},
 };
-use structopt::StructOpt;
 
 const DEFAULT_PROCESSES: usize = 10;
 const DEFAULT_ITERATIONS_PER_PROCESS: usize = 10;
@@ -204,7 +204,7 @@ mod callgrind {
 ///
 /// The total number of samples taken for each Wasm benchmark is `PROCESSES *
 /// NUMBER_OF_ITERATIONS_PER_PROCESS`.
-#[derive(StructOpt, Debug)]
+#[derive(Parser, Debug)]
 pub struct BenchmarkCommand {
     /// The path to the file(s) to benchmark. This accepts one or more:
     ///
@@ -217,11 +217,7 @@ pub struct BenchmarkCommand {
     ///   the `*.suite` file.
     ///
     /// By default, this will use `benchmarks/default.suite`.
-    #[structopt(
-        index = 1,
-        default_value = "benchmarks/default.suite",
-        value_name = "FILE"
-    )]
+    #[arg(default_value = "benchmarks/default.suite", value_name = "FILE")]
     benchmarks: Vec<BenchmarkOrSuite>,
 
     /// The benchmark engine(s) with which to run the benchmark.
@@ -229,13 +225,13 @@ pub struct BenchmarkCommand {
     /// This is one or more paths to a shared library implementing the
     /// benchmarking engine specification. See `engines/wasmtime` for an example
     /// script to build an engine.
-    #[structopt(long("engine"), short("e"), value_name = "PATH", empty_values = false)]
+    #[arg(long = "engine", short = 'e', value_name = "PATH")]
     engines: Vec<String>,
 
     /// Configure an engine using engine-specific flags. (For the Wasmtime
     /// engine, these can be a subset of flags from `wasmtime run --help`).
-    #[structopt(
-        long("engine-flags"),
+    #[arg(
+        long = "engine-flags",
         value_name = "ENGINE_FLAGS",
         allow_hyphen_values = true
     )]
@@ -245,7 +241,7 @@ pub struct BenchmarkCommand {
     ///
     /// Defaults to `10`, unless using the `callgrind` measure, in which case the
     /// default is `3`.
-    #[structopt(long = "processes", value_name = "PROCESSES")]
+    #[arg(long = "processes", value_name = "PROCESSES")]
     processes: Option<usize>,
 
     /// Override the "engine" name; this is useful if running experiments that might
@@ -253,14 +249,14 @@ pub struct BenchmarkCommand {
     ///
     /// If multiple engines are provided, the order of names provided here should
     /// match the order of the engines specified.
-    #[structopt(long = "name", short = "n")]
+    #[arg(long = "name", short = 'n')]
     names: Option<Vec<String>>,
 
     /// How many times should we run a benchmark in a single process?
     ///
     /// Defaults to `10`, unless using the `callgrind` measure, in which case the
     /// default is `1`.
-    #[structopt(
+    #[arg(
         long = "iterations-per-process",
         value_name = "NUMBER_OF_ITERATIONS_PER_PROCESS"
     )]
@@ -268,17 +264,17 @@ pub struct BenchmarkCommand {
 
     /// Output raw data, rather than the summarized, human-readable analysis
     /// results.
-    #[structopt(long)]
+    #[arg(long)]
     raw: bool,
 
     /// The format of the raw output data when `--raw` is used. Either 'json' or
     /// 'csv'.
-    #[structopt(short = "f", long = "output-format", default_value = "json")]
+    #[arg(short = 'f', long = "output-format", default_value = "json")]
     output_format: Format,
 
     /// Path to a file which will contain the output data, or nothing to print
     /// to stdout (default).
-    #[structopt(short = "o", long = "output-file")]
+    #[arg(short = 'o', long = "output-file")]
     output_file: Option<String>,
 
     /// The type of measurement to use (cycles, insts-retired, perf-counters,
@@ -292,7 +288,7 @@ pub struct BenchmarkCommand {
     /// `callgrind` defaults to fewer processes and iterations per process
     /// because it runs the benchmarking processes under Valgrind, which is
     /// slower but also more deterministic and less noisy.
-    #[structopt(long = "measure", short = "m", multiple = true)]
+    #[arg(long = "measure", short = 'm', action = clap::ArgAction::Append)]
     measures: Vec<MeasureType>,
 
     /// Pass this flag to only run benchmarks over "small" workloads (rather
@@ -307,36 +303,36 @@ pub struct BenchmarkCommand {
     /// of truth, and any cases where results differ between the small and
     /// default workloads, the results from the small workloads should be
     /// ignored.
-    #[structopt(long, alias = "small-workload")]
+    #[arg(long, alias = "small-workload")]
     small_workloads: bool,
 
     /// The directory to preopen as the benchmark working directory. If the
     /// benchmark accesses files using WASI, it will see this directory as its
     /// current working directory (i.e. `.`). If the working directory is not
     /// specified, the Wasm file's parent directory is used instead.
-    #[structopt(short("d"), long("working-dir"), parse(from_os_str))]
+    #[arg(short = 'd', long = "working-dir")]
     working_dir: Option<PathBuf>,
 
     /// Benchmark only the given phase (compilation, instantiation, or
     /// execution). Benchmarks all phases if omitted.
-    #[structopt(long("benchmark-phase"))]
+    #[arg(long = "benchmark-phase")]
     benchmark_phase: Option<Phase>,
 
     /// The significance level for confidence intervals. Typical values are 0.01
     /// and 0.05, which correspond to 99% and 95% confidence respectively. This
     /// is ignored when using `--raw` or when there aren't exactly two engines
     /// supplied.
-    #[structopt(short, long, default_value = "0.01")]
+    #[arg(short, long, default_value = "0.01")]
     significance_level: f64,
 
     /// Pin all benchmark iterations in a process to a single core. See
     /// `cpu_affinity` in the `sightglass-recorder` crate for more information.
-    #[structopt(long)]
+    #[arg(long)]
     pin: bool,
 
     /// Keep log files after successful benchmark runs. By default, logs are
     /// only kept on failures.
-    #[structopt(short = "k", long = "keep-logs")]
+    #[arg(short = 'k', long = "keep-logs")]
     keep_logs: bool,
 }
 
diff --git a/crates/cli/src/clean.rs b/crates/cli/src/clean.rs
index fd0ca6d8..6dd2765b 100644
--- a/crates/cli/src/clean.rs
+++ b/crates/cli/src/clean.rs
@@ -1,10 +1,10 @@
 use anyhow::{Context, Result};
+use clap::Parser;
 use regex::Regex;
-use structopt::StructOpt;
 
 /// Remove the log files emitted in Sightglass runs.
-#[derive(StructOpt, Debug)]
-#[structopt(name = "clean")]
+#[derive(Parser, Debug)]
+#[command(name = "clean")]
 pub struct CleanCommand {}
 
 impl CleanCommand {
@@ -51,9 +51,16 @@ impl CleanCommand {
 
                 // Okay! It's one of our log files!
                 log::info!("Removing log file: {}", path.display());
-                std::fs::remove_file(&path)
-                    .with_context(|| format!("failed to remove {}", path.display()))?;
-                removed_count += 1;
+                match std::fs::remove_file(&path) {
+                    Ok(()) => removed_count += 1,
+                    Err(e) if e.kind() == std::io::ErrorKind::NotFound => {
+                        // File was already removed (e.g. by a parallel process); that's fine.
+                    }
+                    Err(e) => {
+                        return Err(e)
+                            .with_context(|| format!("failed to remove {}", path.display()));
+                    }
+                }
             }
         }
 
diff --git a/crates/cli/src/effect_size.rs b/crates/cli/src/effect_size.rs
index d806f74c..fe965565 100644
--- a/crates/cli/src/effect_size.rs
+++ b/crates/cli/src/effect_size.rs
@@ -1,33 +1,33 @@
 use anyhow::Result;
+use clap::Parser;
 use sightglass_analysis::{effect_size, summarize};
 use sightglass_data::Format;
 use std::{
     fs::File,
     io::{self, BufReader},
 };
-use structopt::StructOpt;
 
 /// Calculate the effect size (and associated confidence interval) between the
 /// results for two different engines.
-#[derive(Debug, StructOpt)]
-#[structopt(name = "effect-size")]
+#[derive(Debug, Parser)]
+#[command(name = "effect-size")]
 pub struct EffectSizeCommand {
     /// Path to the file(s) that will be read from, or none to indicate stdin (default).
-    #[structopt(short = "f")]
+    #[arg(short = 'f')]
     input_file: Option<Vec<String>>,
 
     /// The format of the input data. Either 'json' or 'csv'.
-    #[structopt(short = "i", long = "input-format", default_value = "json")]
+    #[arg(short = 'i', long = "input-format", default_value = "json")]
     input_format: Format,
 
     /// The format of the output data. Either 'json' or 'csv'; if unspecified, print the output in
     /// human-readable form.
-    #[structopt(short = "o", long = "output-format")]
+    #[arg(short = 'o', long = "output-format")]
     output_format: Option<Format>,
 
     /// The significance level for the confidence interval. Typical values are
     /// 0.01 and 0.05, which correspond to 99% and 95% confidence respectively.
-    #[structopt(short, long, default_value = "0.01")]
+    #[arg(short, long, default_value = "0.01")]
     significance_level: f64,
 }
 
diff --git a/crates/cli/src/fingerprint.rs b/crates/cli/src/fingerprint.rs
index 23a5561f..898583d8 100644
--- a/crates/cli/src/fingerprint.rs
+++ b/crates/cli/src/fingerprint.rs
@@ -1,25 +1,25 @@
 use anyhow::Result;
+use clap::Parser;
 use sightglass_data::Format;
 use sightglass_fingerprint::{Benchmark, Engine, Machine};
 use std::{io, path::PathBuf};
-use structopt::StructOpt;
 
 /// Gather information about the current machine, a Wasm benchmark, or a Wasm
 /// engine and print the results to `stdout`.
-#[derive(Debug, StructOpt)]
-#[structopt(name = "fingerprint")]
+#[derive(Debug, Parser)]
+#[command(name = "fingerprint")]
 pub struct FingerprintCommand {
     /// The kind of item to fingerprint. One of: 'benchmark', 'engine', 'machine'.
-    #[structopt(short = "k", long = "kind")]
+    #[arg(short = 'k', long = "kind")]
     kind: Kind,
 
     /// The format of the output data. Either 'json' or 'csv'.
-    #[structopt(short = "o", long = "output-format", default_value = "json")]
+    #[arg(short = 'o', long = "output-format", default_value = "json")]
     output_format: Format,
 
     /// The optional path to the file to fingerprint; not all kinds
     /// fingerprinting require a file (e.g., `--kind machine`).
-    #[structopt(index = 1, value_name = "FILE", parse(from_os_str))]
+    #[arg(value_name = "FILE")]
     file: Option<PathBuf>,
 }
 
diff --git a/crates/cli/src/main.rs b/crates/cli/src/main.rs
index bb13bb58..8d789413 100644
--- a/crates/cli/src/main.rs
+++ b/crates/cli/src/main.rs
@@ -11,13 +11,13 @@ mod validate;
 
 use anyhow::Result;
 use benchmark::BenchmarkCommand;
+use clap::Parser;
 use clean::CleanCommand;
 use effect_size::EffectSizeCommand;
 use fingerprint::FingerprintCommand;
 use log::trace;
 use pca_metrics::PcaMetricsCommand;
 use report::ReportCommand;
-use structopt::{clap::AppSettings, StructOpt};
 use summarize::SummarizeCommand;
 use upload::UploadCommand;
 use validate::ValidateCommand;
@@ -25,20 +25,14 @@ use validate::ValidateCommand;
 /// Main entry point for CLI.
 fn main() -> Result<()> {
     pretty_env_logger::init();
-    let command = SightglassCommand::from_args();
+    let command = SightglassCommand::parse();
     command.execute()?;
     Ok(())
 }
 
 /// The sightglass benchmark runner.
-#[derive(StructOpt, Debug)]
-#[structopt(
-    version = env!("CARGO_PKG_VERSION"),
-    global_settings = &[
-        AppSettings::VersionlessSubcommands,
-        AppSettings::ColoredHelp
-    ],
-)]
+#[derive(Parser, Debug)]
+#[command(version, propagate_version = true)]
 enum SightglassCommand {
     Benchmark(BenchmarkCommand),
     Clean(CleanCommand),
diff --git a/crates/cli/src/pca_metrics.rs b/crates/cli/src/pca_metrics.rs
index 42fd81fc..c27f7cca 100644
--- a/crates/cli/src/pca_metrics.rs
+++ b/crates/cli/src/pca_metrics.rs
@@ -7,20 +7,20 @@ mod static_metrics;
 use crate::suite::BenchmarkOrSuite;
 use anyhow::{Context, Result};
 use category::{Category, NUM_CATEGORIES};
+use clap::Parser;
 use dynamic_metrics::{dynamic_metrics, make_engine};
 use serde::Serialize;
 use sightglass_build::get_engine_filename;
 use static_metrics::static_metrics;
 use std::path::{Path, PathBuf};
-use structopt::StructOpt;
 
 /// Capture benchmark metrics for principal component analysis (PCA).
-#[derive(Debug, StructOpt)]
-#[structopt(name = "pca-metrics")]
+#[derive(Debug, Parser)]
+#[command(name = "pca-metrics")]
 pub struct PcaMetricsCommand {
     /// The optional file path to write output to. Writes output to stdout if
     /// omitted.
-    #[structopt(long, short, parse(from_os_str))]
+    #[arg(long, short)]
     output: Option<PathBuf>,
 
     /// Optionally bound each benchmark's execution to this many units of fuel.
@@ -31,13 +31,13 @@ pub struct PcaMetricsCommand {
     ///
     /// This primarily exists to make testing this command easier, and shouldn't
     /// be used when doing full PCA.
-    #[structopt(long)]
+    #[arg(long)]
     fuel: Option<u64>,
 
     /// The benchmark engine with which to run Callgrind measurements.
     ///
     /// Defaults to the Wasmtime engine library in this repository.
-    #[structopt(long, short, parse(from_os_str))]
+    #[arg(long, short)]
     engine: Option<PathBuf>,
 
     /// The Wasm benchmarks whose PCA metrics should be taken.
diff --git a/crates/cli/src/report.rs b/crates/cli/src/report.rs
index 620a92d0..1978e1c8 100644
--- a/crates/cli/src/report.rs
+++ b/crates/cli/src/report.rs
@@ -1,5 +1,5 @@
+use clap::Parser;
 use std::{
-    cell::Cell,
     collections::HashMap,
     fs::File,
     hash::{Hash, Hasher},
@@ -10,7 +10,6 @@ use std::{
 use serde::Serialize;
 use sightglass_analysis::report_stats::{calculate_benchmark_stats, BenchmarkStats, ReportConfig};
 use sightglass_data::{extract_benchmark_name, Engine, Format, Measurement, Phase};
-use structopt::StructOpt;
 use vega_lite_4::{
     AxisBuilder, ColorClassBuilder, EdEncodingBuilder, LegendBuilder, Mark, NormalizedSpecBuilder,
     XClassBuilder, YClassBuilder,
@@ -19,37 +18,37 @@ use vega_lite_4::{
 const TEMPLATE: &str = include_str!(concat!(env!("CARGO_MANIFEST_DIR"), "/src/report.jinja"));
 
 /// Generate an HTML report for a given set of raw inputs
-#[derive(Debug, StructOpt)]
-#[structopt(name = "report")]
+#[derive(Debug, Parser)]
+#[command(name = "report")]
 pub struct ReportCommand {
     /// The format of the input data. Either 'json' or 'csv'; if not provided
     /// then we will attempt to infer it from provided filenames, falling back to json.
-    #[structopt(short = "i", long = "input-format")]
+    #[arg(short = 'i', long = "input-format")]
     input_format: Option<Format>,
 
     /// Output HTML file path
-    #[structopt(short = "o", long = "output-file", default_value = "report.html")]
+    #[arg(short = 'o', long = "output-file", default_value = "report.html")]
     output_path: PathBuf,
 
     /// Name of the baseline to use; if not provided, the first engine encountered
     /// in the ordered input files will be used.
-    #[structopt(short = "b", long = "baseline-engine")]
+    #[arg(short = 'b', long = "baseline-engine")]
     baseline_engine: Option<String>,
 
     /// Significance level for statistical tests (default: 0.05 for 95% confidence)
-    #[structopt(long = "significance-level", default_value = "0.05")]
+    #[arg(long = "significance-level", default_value = "0.05")]
     significance_level: f64,
 
     /// Primary event to analyze (default: cycles)
-    #[structopt(long = "event", default_value = "cycles")]
+    #[arg(long = "event", default_value = "cycles")]
     primary_event: String,
 
     /// Target phase to analyze (default: execution)
-    #[structopt(long = "phase", default_value = "execution")]
+    #[arg(long = "phase", default_value = "execution")]
     target_phase: Phase,
 
     /// Path to the file(s) that will be read from, or none to indicate stdin (default).
-    #[structopt(min_values = 1)]
+    #[arg(num_args = 1..)]
     input_files: Vec<PathBuf>,
 }
 
@@ -119,9 +118,7 @@ fn parse_input(
     let format = format
         .or_else(|| match path.as_ref().extension()?.to_str()? {
             "json" => Some(Format::Json),
-            "csv" => Some(Format::Csv {
-                headers: Cell::new(true),
-            }),
+            "csv" => Some(Format::Csv { headers: true }),
             _ => None,
         })
         .unwrap_or(Format::Json);
@@ -360,7 +357,7 @@ impl ReportCommand {
         let mut all_measurements = Vec::new();
 
         for input_file in &self.input_files {
-            let measurements = parse_input(self.input_format.clone(), input_file)?;
+            let measurements = parse_input(self.input_format, input_file)?;
             all_measurements.extend(measurements);
         }
 
diff --git a/crates/cli/src/suite.rs b/crates/cli/src/suite.rs
index 1d8f1560..83af1f5c 100644
--- a/crates/cli/src/suite.rs
+++ b/crates/cli/src/suite.rs
@@ -14,7 +14,7 @@ use std::{
 };
 
 /// Decide between a suite of benchmarks or an individual benchmark file.
-#[derive(Debug)]
+#[derive(Clone, Debug)]
 pub enum BenchmarkOrSuite {
     Suite(Suite),
     Benchmark(PathBuf),
@@ -53,7 +53,7 @@ impl FromStr for BenchmarkOrSuite {
     }
 }
 
-#[derive(Debug)]
+#[derive(Clone, Debug)]
 pub struct Suite {
     path: PathBuf,
     benchmarks: Vec<PathBuf>,
diff --git a/crates/cli/src/summarize.rs b/crates/cli/src/summarize.rs
index 39f0c922..a33d5bee 100644
--- a/crates/cli/src/summarize.rs
+++ b/crates/cli/src/summarize.rs
@@ -1,29 +1,29 @@
 use anyhow::Result;
+use clap::Parser;
 use sightglass_analysis::summarize;
 use sightglass_data::Format;
 use std::{
     fs::File,
     io::{self, BufReader},
 };
-use structopt::StructOpt;
 
 /// Summarize benchmark output; accepts raw benchmark results in `stdin` (i.e.,
 /// from `sightglass-cli benchmark ...`) and prints the summarized results to
 /// `stdout`.
-#[derive(Debug, StructOpt)]
-#[structopt(name = "summarize")]
+#[derive(Debug, Parser)]
+#[command(name = "summarize")]
 pub struct SummarizeCommand {
     /// Path to the file(s) that will be read from, or none to indicate stdin (default).
-    #[structopt(short = "f")]
+    #[arg(short = 'f')]
     input_file: Option<Vec<String>>,
 
     /// The format of the input data. Either 'json' or 'csv'.
-    #[structopt(short = "i", long = "input-format", default_value = "json")]
+    #[arg(short = 'i', long = "input-format", default_value = "json")]
     input_format: Format,
 
     /// The format of the output data. Either 'json' or 'csv'; if unspecified, print the output in
     /// human-readable form.
-    #[structopt(short = "o", long = "output-format")]
+    #[arg(short = 'o', long = "output-format")]
     output_format: Option<Format>,
 }
 
diff --git a/crates/cli/src/upload.rs b/crates/cli/src/upload.rs
index ba71927b..91ef5878 100644
--- a/crates/cli/src/upload.rs
+++ b/crates/cli/src/upload.rs
@@ -1,47 +1,47 @@
 use anyhow::{Context, Result};
+use clap::Parser;
 use sightglass_data::{Format, Measurement};
 use sightglass_upload::{upload, upload_package, MeasurementPackage};
 use std::{
     fs::File,
     io::{self, BufReader, Read},
 };
-use structopt::StructOpt;
 
 /// Upload benchmark output to an ElasticSearch server; accepts raw benchmark
 /// results in `stdin` (i.e., from `sightglass-cli benchmark ...`).
-#[derive(Debug, StructOpt)]
-#[structopt(name = "upload-elastic")]
+#[derive(Debug, Parser)]
+#[command(name = "upload-elastic")]
 pub struct UploadCommand {
     /// The format of the input data. Either 'json' or 'csv'.
-    #[structopt(short = "i", long = "input-format", default_value = "json")]
+    #[arg(short = 'i', long = "input-format", default_value = "json")]
     input_format: Format,
 
     /// Path to the file that will be read from, or none to indicate stdin
     /// (default).
-    #[structopt(short = "f", long = "input-file")]
+    #[arg(short = 'f', long = "input-file")]
     input_file: Option<String>,
 
     /// The URL of a server receiving results; this command only understands how
     /// to upload results to an ElasticSearch server; e.g.,
     /// `http://localhost:9200`.
-    #[structopt(index = 1, default_value = "http://localhost:9200", value_name = "URL")]
+    #[arg(default_value = "http://localhost:9200", value_name = "URL")]
     server: String,
 
     /// Setting this flag will prevent any uploading to the server. Instead,
     /// the command will emit a JSON "package" to stdout that can be used to
     /// upload at a later time, see `--from-package`.
-    #[structopt(short = "d", long = "dry-run")]
+    #[arg(short = 'd', long = "dry-run")]
     dry_run: bool,
 
     /// Path to a file containing a package of measurements and fingerprint data
     /// to be uploaded. If this is set, `--input-file` and `--input-format` are
     /// ignored.
-    #[structopt(short = "p", long = "from-package")]
+    #[arg(short = 'p', long = "from-package")]
     from_package: Option<String>,
 
     /// The number of measurements to upload together; this can speed up the
     /// upload. Defaults to `2000`.
-    #[structopt(short = "b", long = "batch-size", default_value = "2000")]
+    #[arg(short = 'b', long = "batch-size", default_value = "2000")]
     batch_size: usize,
 }
 
diff --git a/crates/cli/src/validate.rs b/crates/cli/src/validate.rs
index 6124784e..85741043 100644
--- a/crates/cli/src/validate.rs
+++ b/crates/cli/src/validate.rs
@@ -1,20 +1,15 @@
 use anyhow::Result;
+use clap::Parser;
 use sightglass_build::WasmBenchmark;
 use std::path::PathBuf;
-use structopt::StructOpt;
 
 /// Check that a Wasm benchmark is runnable in this tool.
-#[derive(StructOpt, Debug)]
-#[structopt(name = "validate")]
+#[derive(Parser, Debug)]
+#[command(name = "validate")]
 pub struct ValidateCommand {
     /// The path to the WebAssembly benchmark module; this file should import `bench.start` and
     /// `bench.end`.
-    #[structopt(
-        index = 1,
-        required = true,
-        value_name = "WASMFILE",
-        parse(from_os_str)
-    )]
+    #[arg(required = true, value_name = "WASMFILE")]
     benchmark: PathBuf,
 }
 
diff --git a/crates/cli/tests/all/benchmark.rs b/crates/cli/tests/all/benchmark.rs
index 1ce18645..23fe9b02 100644
--- a/crates/cli/tests/all/benchmark.rs
+++ b/crates/cli/tests/all/benchmark.rs
@@ -3,7 +3,7 @@ use assert_cmd::prelude::*;
 use predicates::prelude::*;
 use sightglass_data::Measurement;
 use std::path::PathBuf;
-
+use tempfile::TempDir;
 #[test]
 fn benchmark_phase_compilation() {
     sightglass_cli_benchmark()
@@ -194,3 +194,64 @@ fn benchmark_effect_size() -> anyhow::Result<()> {
 
     Ok(())
 }
+
+/// --output-file writes raw JSON to a file rather than stdout.
+#[test]
+fn benchmark_output_file() -> anyhow::Result<()> {
+    let dir = TempDir::new()?;
+    let out = dir.path().join("out.json");
+    sightglass_cli_benchmark()
+        .arg("--raw")
+        .arg("--processes")
+        .arg("1")
+        .arg("--iterations-per-process")
+        .arg("1")
+        .arg("--output-file")
+        .arg(&out)
+        .arg(benchmark("noop"))
+        .assert()
+        .success();
+    assert!(out.exists(), "output file was not created");
+    let content = std::fs::read_to_string(&out)?;
+    assert!(
+        serde_json::from_str::<serde_json::Value>(&content).is_ok(),
+        "output file is not valid JSON"
+    );
+    Ok(())
+}
+
+/// --name overrides the engine name in the output.
+#[test]
+fn benchmark_name_override() {
+    sightglass_cli_benchmark()
+        .arg("--raw")
+        .arg("--processes")
+        .arg("1")
+        .arg("--iterations-per-process")
+        .arg("1")
+        .arg("--name")
+        .arg("my-custom-engine")
+        .arg("--")
+        .arg(benchmark("noop"))
+        .assert()
+        .success()
+        .stdout(predicate::str::contains("my-custom-engine"));
+}
+
+/// --measure time produces output with nanosecond events.
+#[test]
+fn benchmark_measure_noop() {
+    sightglass_cli_benchmark()
+        .arg("--raw")
+        .arg("--processes")
+        .arg("1")
+        .arg("--iterations-per-process")
+        .arg("1")
+        .arg("--measure")
+        .arg("time")
+        .arg("--")
+        .arg(benchmark("noop"))
+        .assert()
+        .success()
+        .stdout(predicate::str::contains("nanoseconds"));
+}
diff --git a/crates/cli/tests/all/clean.rs b/crates/cli/tests/all/clean.rs
new file mode 100644
index 00000000..6b952119
--- /dev/null
+++ b/crates/cli/tests/all/clean.rs
@@ -0,0 +1,11 @@
+use super::util::sightglass_cli;
+use assert_cmd::prelude::*;
+
+/// clean does not accept unknown flags.
+#[test]
+fn clean_rejects_unknown_flags() {
+    sightglass_cli()
+        .args(["clean", "--unknown-flag"])
+        .assert()
+        .failure();
+}
diff --git a/crates/cli/tests/all/effect_size.rs b/crates/cli/tests/all/effect_size.rs
new file mode 100644
index 00000000..2d59ee2a
--- /dev/null
+++ b/crates/cli/tests/all/effect_size.rs
@@ -0,0 +1,98 @@
+use super::util::sightglass_cli;
+use assert_cmd::prelude::*;
+use predicates::prelude::*;
+
+fn multi_engine_v38_json() -> &'static str {
+    concat!(env!("CARGO_MANIFEST_DIR"), "/tests/multi_engine_v38.json")
+}
+
+fn multi_engine_v38_epoch_json() -> &'static str {
+    concat!(
+        env!("CARGO_MANIFEST_DIR"),
+        "/tests/multi_engine_v38_epoch.json"
+    )
+}
+
+/// effect-size reads two-engine JSON and prints a human-readable comparison by default.
+#[test]
+fn effect_size_human_readable() {
+    sightglass_cli()
+        .args([
+            "effect-size",
+            "-f",
+            multi_engine_v38_json(),
+            "-f",
+            multi_engine_v38_epoch_json(),
+        ])
+        .assert()
+        .success()
+        .stdout(
+            predicate::str::contains("cycles").and(
+                predicate::str::contains("Δ = ")
+                    .or(predicate::str::contains("No difference in performance.")),
+            ),
+        );
+}
+
+/// effect-size with --output-format json produces parseable JSON.
+#[test]
+fn effect_size_output_format_json() {
+    let assert = sightglass_cli()
+        .args([
+            "effect-size",
+            "-f",
+            multi_engine_v38_json(),
+            "-f",
+            multi_engine_v38_epoch_json(),
+            "--output-format",
+            "json",
+        ])
+        .assert()
+        .success();
+
+    let stdout = std::str::from_utf8(&assert.get_output().stdout).unwrap();
+    assert!(
+        serde_json::from_str::<serde_json::Value>(stdout).is_ok(),
+        "stdout was not valid JSON: {stdout}"
+    );
+}
+
+/// effect-size with --output-format csv produces a CSV header row.
+#[test]
+fn effect_size_output_format_csv() {
+    sightglass_cli()
+        .args([
+            "effect-size",
+            "-f",
+            multi_engine_v38_json(),
+            "-f",
+            multi_engine_v38_epoch_json(),
+            "--output-format",
+            "csv",
+        ])
+        .assert()
+        .success()
+        .stdout(predicate::str::contains("mean"));
+}
+
+/// effect-size with a nonexistent input file fails with an error.
+#[test]
+fn effect_size_missing_file_fails() {
+    sightglass_cli()
+        .args(["effect-size", "-f", "nonexistent_file_xyz.json"])
+        .assert()
+        .failure();
+}
+
+/// effect-size with a single-engine file (no comparison possible) exits non-zero.
+#[test]
+fn effect_size_single_engine_fails() {
+    sightglass_cli()
+        .args([
+            "effect-size",
+            "-f",
+            concat!(env!("CARGO_MANIFEST_DIR"), "/tests/results.json"),
+        ])
+        .assert()
+        .failure();
+}
diff --git a/crates/cli/tests/all/main.rs b/crates/cli/tests/all/main.rs
index 0fd72683..08f468b8 100644
--- a/crates/cli/tests/all/main.rs
+++ b/crates/cli/tests/all/main.rs
@@ -1,9 +1,13 @@
 mod benchmark;
+mod clean;
+mod effect_size;
 mod fingerprint;
 mod help;
 mod pca_metrics;
 mod report;
+mod summarize;
 mod upload;
 mod util;
+mod validate;
 
 fn main() {}
diff --git a/crates/cli/tests/all/summarize.rs b/crates/cli/tests/all/summarize.rs
new file mode 100644
index 00000000..dc6aeed5
--- /dev/null
+++ b/crates/cli/tests/all/summarize.rs
@@ -0,0 +1,55 @@
+use super::util::sightglass_cli;
+use assert_cmd::prelude::*;
+use predicates::prelude::*;
+
+fn results_json() -> &'static str {
+    concat!(env!("CARGO_MANIFEST_DIR"), "/tests/results.json")
+}
+
+/// summarize reads raw JSON and prints a human-readable table by default.
+#[test]
+fn summarize_human_readable() {
+    sightglass_cli()
+        .args(["summarize", "-f", results_json()])
+        .assert()
+        .success()
+        .stdout(
+            predicate::str::contains("compilation")
+                .or(predicate::str::contains("Compilation"))
+                .and(predicate::str::contains("cycles")),
+        );
+}
+
+/// summarize --output-format json produces parseable JSON.
+#[test]
+fn summarize_output_format_json() {
+    let assert = sightglass_cli()
+        .args(["summarize", "-f", results_json(), "--output-format", "json"])
+        .assert()
+        .success();
+
+    let stdout = std::str::from_utf8(&assert.get_output().stdout).unwrap();
+    assert!(
+        serde_json::from_str::<serde_json::Value>(stdout).is_ok(),
+        "stdout was not valid JSON: {stdout}"
+    );
+}
+
+/// summarize --output-format csv produces a CSV header row.
+#[test]
+fn summarize_output_format_csv() {
+    sightglass_cli()
+        .args(["summarize", "-f", results_json(), "--output-format", "csv"])
+        .assert()
+        .success()
+        .stdout(predicate::str::contains("mean"));
+}
+
+/// summarize with a nonexistent input file fails.
+#[test]
+fn summarize_missing_file_fails() {
+    sightglass_cli()
+        .args(["summarize", "-f", "nonexistent_xyz.json"])
+        .assert()
+        .failure();
+}
diff --git a/crates/cli/tests/all/validate.rs b/crates/cli/tests/all/validate.rs
new file mode 100644
index 00000000..0b9313cb
--- /dev/null
+++ b/crates/cli/tests/all/validate.rs
@@ -0,0 +1,24 @@
+use super::util::{benchmark, sightglass_cli};
+use assert_cmd::prelude::*;
+
+/// validate accepts a valid benchmark .wasm file and exits successfully.
+#[test]
+fn validate_valid_benchmark() {
+    sightglass_cli()
+        .arg("validate")
+        .arg(benchmark("noop"))
+        .assert()
+        .success();
+}
+
+/// validate rejects a non-wasm file (e.g. a JSON fixture).
+#[test]
+fn validate_non_wasm_file_fails() {
+    sightglass_cli()
+        .args([
+            "validate",
+            concat!(env!("CARGO_MANIFEST_DIR"), "/tests/results.json"),
+        ])
+        .assert()
+        .failure();
+}
diff --git a/crates/data/src/format.rs b/crates/data/src/format.rs
index 7a8e54eb..68d0282b 100644
--- a/crates/data/src/format.rs
+++ b/crates/data/src/format.rs
@@ -4,29 +4,26 @@ use core::fmt;
 use csv::ReaderBuilder;
 use serde::{de::DeserializeOwned, Serialize};
 use std::{
-    cell::Cell,
     io::{Read, Write},
     str::FromStr,
 };
 
 /// Describes the input/output formats for the data structures in the `sightglass-data` crate.
-#[derive(Clone, Debug)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub enum Format {
     /// The JSON format.
     Json,
     /// The CSV format.
     Csv {
-        /// Indicates whether the CSV headers are present during reading and writing.
-        headers: Cell<bool>,
+        /// Whether to include a header row when reading or writing.
+        headers: bool,
     },
 }
 
 impl Format {
     /// Construct a CSV formatter; allows setting the `headers` parameter more easily.
     pub fn csv(headers: bool) -> Self {
-        Self::Csv {
-            headers: Cell::from(headers),
-        }
+        Self::Csv { headers }
     }
 
     /// Read a list of `T` using the selected format.
@@ -39,7 +36,7 @@ impl Format {
             Format::Json => serde_json::from_reader(reader)?,
             Format::Csv { headers } => {
                 let mut reader = ReaderBuilder::new()
-                    .has_headers(headers.take())
+                    .has_headers(*headers)
                     .from_reader(reader);
                 reader.deserialize().map(|r| r.unwrap()).collect()
             }
@@ -56,7 +53,7 @@ impl Format {
             Format::Json => serde_json::to_writer(writer, objects)?,
             Format::Csv { headers } => {
                 let mut csv = csv::WriterBuilder::new()
-                    .has_headers(headers.take())
+                    .has_headers(*headers)
                     .from_writer(writer);
                 for o in objects {
                     csv.serialize(o)?;
@@ -67,7 +64,7 @@ impl Format {
         Ok(())
     }
 
-    /// Write a list of `T` using the selected format.
+    /// Write a single `T` using the selected format.
     pub fn write_one<T, W>(&self, object: T, writer: W) -> Result<()>
     where
         T: Serialize,
@@ -77,7 +74,7 @@ impl Format {
             Format::Json => serde_json::to_writer(writer, &object)?,
             Format::Csv { headers } => {
                 let mut csv = csv::WriterBuilder::new()
-                    .has_headers(headers.take())
+                    .has_headers(*headers)
                     .from_writer(writer);
                 csv.serialize(&object)?;
                 csv.flush()?;
@@ -102,9 +99,7 @@ impl FromStr for Format {
     fn from_str(s: &str) -> Result<Self, &'static str> {
         match s {
             "json" => Ok(Format::Json),
-            "csv" => Ok(Format::Csv {
-                headers: Cell::from(true),
-            }),
+            "csv" => Ok(Format::Csv { headers: true }),
             _ => Err("output format must be either 'json' or 'csv'"),
         }
     }