diff --git a/protokt-codegen/src/main/kotlin/protokt/v1/codegen/generate/FileDescriptorEncoding.kt b/protokt-codegen/src/main/kotlin/protokt/v1/codegen/generate/FileDescriptorEncoding.kt
index edd46adc1..fa40527f2 100644
--- a/protokt-codegen/src/main/kotlin/protokt/v1/codegen/generate/FileDescriptorEncoding.kt
+++ b/protokt-codegen/src/main/kotlin/protokt/v1/codegen/generate/FileDescriptorEncoding.kt
@@ -43,14 +43,14 @@ private const val BYTES_PER_PART = BYTES_PER_LINE * LINES_PER_PART
 // This makes huge bytecode files and can easily hit the compiler's internal
 // code size limits (error "code to large").  String literals are apparently
 // embedded raw, which is what we want.
-fun encodeFileDescriptor(fileDescriptorProto: FileDescriptorProto): List<List<String>> {
-    val parts = mutableListOf<MutableList<String>>()
+fun encodeFileDescriptor(fileDescriptorProto: FileDescriptorProto): List<String> {
+    val parts = mutableListOf<String>()
     val bytes = fileDescriptorProto.toByteArray()
     for (i in bytes.indices step BYTES_PER_LINE) {
         if (i % BYTES_PER_PART == 0) {
-            parts.add(mutableListOf())
+            parts.add("")
         }
-        parts.last().add(escape(bytes.asSequence().drop(i).take(BYTES_PER_LINE)))
+        parts[parts.size - 1] += escape(bytes.asSequence().drop(i).take(BYTES_PER_LINE))
     }
     return parts
 }
diff --git a/protokt-codegen/src/main/kotlin/protokt/v1/codegen/generate/FileDescriptorResolver.kt b/protokt-codegen/src/main/kotlin/protokt/v1/codegen/generate/FileDescriptorResolver.kt
index 33261ab68..3355ad5c5 100644
--- a/protokt-codegen/src/main/kotlin/protokt/v1/codegen/generate/FileDescriptorResolver.kt
+++ b/protokt-codegen/src/main/kotlin/protokt/v1/codegen/generate/FileDescriptorResolver.kt
@@ -78,14 +78,11 @@ private constructor(
         return FileDescriptorInfo(type, properties)
     }
 
-    private fun descriptorLines() =
-        fileDescriptorParts()
-            .map { arrayParts ->
-                arrayParts
-                    .map { CodeBlock.of("\"%L\"", it) }
-                    .joinToCode(" +\n")
-            }
-            .joinToCode(",\n")
+    private fun descriptorLines(): CodeBlock {
+        val sb = StringBuilder()
+        fileDescriptorParts().forEach(sb::append)
+        return CodeBlock.of("\"%L\"", sb.toString().bindSpaces())
+    }
 
     private fun fileDescriptorParts() =
         encodeFileDescriptor(
diff --git a/protokt-codegen/src/main/kotlin/protokt/v1/codegen/generate/MessageGenerator.kt b/protokt-codegen/src/main/kotlin/protokt/v1/codegen/generate/MessageGenerator.kt
index 625319cc7..7a89412fe 100644
--- a/protokt-codegen/src/main/kotlin/protokt/v1/codegen/generate/MessageGenerator.kt
+++ b/protokt-codegen/src/main/kotlin/protokt/v1/codegen/generate/MessageGenerator.kt
@@ -207,7 +207,11 @@ private class MessageGenerator(
                     } else {
                         buildCodeBlock {
                             add("return \"%L(\" +\n", msg.className.simpleName)
-                            toStringLines(properties).forEach(::add)
+                            if (properties.size < 100) {
+                                toStringLines(properties).forEach(::add)
+                            } else {
+                                add(toStringLine(properties))
+                            }
                             add(unknownFieldsToString(prefix = ", "))
                         }
                     }
@@ -226,6 +230,12 @@ private class MessageGenerator(
                 prop.name
             )
         }
+
+    private fun toStringLine(properties: List<PropertyInfo>): CodeBlock {
+        val string = "\"" + properties.joinToString(", ") { "%N=\$%N" } + "\" +\n"
+        val names = properties.flatMap { listOf(it, it) }
+        return CodeBlock.of(string.bindSpaces(), *names.map { it.name }.toTypedArray())
+    }
 }
 
 fun formatDoc(lines: List<String>) =
diff --git a/testing/interop/src/main/proto/protokt/v1/testing/very_large.proto b/testing/interop/src/main/proto/protokt/v1/testing/very_large.proto
new file mode 100644
index 000000000..2e967c519
--- /dev/null
+++ b/testing/interop/src/main/proto/protokt/v1/testing/very_large.proto
@@ -0,0 +1,624 @@
+/*
+ * Copyright (c) 2024 Toast, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+syntax = "proto3";
+
+package protokt.v1.testing;
+
+option java_package = "com.toasttab.protokt.v1.testing";
+
+message VeryLarge {
+  string val1 = 1;
+  string val2 = 2;
+  string val3 = 3;
+  string val4 = 4;
+  string val5 = 5;
+  string val6 = 6;
+  string val7 = 7;
+  string val8 = 8;
+  string val9 = 9;
+  string val10 = 10;
+  string val11 = 11;
+  string val12 = 12;
+  string val13 = 13;
+  string val14 = 14;
+  string val15 = 15;
+  string val16 = 16;
+  string val17 = 17;
+  string val18 = 18;
+  string val19 = 19;
+  string val20 = 20;
+  string val21 = 21;
+  string val22 = 22;
+  string val23 = 23;
+  string val24 = 24;
+  string val25 = 25;
+  string val26 = 26;
+  string val27 = 27;
+  string val28 = 28;
+  string val29 = 29;
+  string val30 = 30;
+  string val31 = 31;
+  string val32 = 32;
+  string val33 = 33;
+  string val34 = 34;
+  string val35 = 35;
+  string val36 = 36;
+  string val37 = 37;
+  string val38 = 38;
+  string val39 = 39;
+  string val40 = 40;
+  string val41 = 41;
+  string val42 = 42;
+  string val43 = 43;
+  string val44 = 44;
+  string val45 = 45;
+  string val46 = 46;
+  string val47 = 47;
+  string val48 = 48;
+  string val49 = 49;
+  string val50 = 50;
+  string val51 = 51;
+  string val52 = 52;
+  string val53 = 53;
+  string val54 = 54;
+  string val55 = 55;
+  string val56 = 56;
+  string val57 = 57;
+  string val58 = 58;
+  string val59 = 59;
+  string val60 = 60;
+  string val61 = 61;
+  string val62 = 62;
+  string val63 = 63;
+  string val64 = 64;
+  string val65 = 65;
+  string val66 = 66;
+  string val67 = 67;
+  string val68 = 68;
+  string val69 = 69;
+  string val70 = 70;
+  string val71 = 71;
+  string val72 = 72;
+  string val73 = 73;
+  string val74 = 74;
+  string val75 = 75;
+  string val76 = 76;
+  string val77 = 77;
+  string val78 = 78;
+  string val79 = 79;
+  string val80 = 80;
+  string val81 = 81;
+  string val82 = 82;
+  string val83 = 83;
+  string val84 = 84;
+  string val85 = 85;
+  string val86 = 86;
+  string val87 = 87;
+  string val88 = 88;
+  string val89 = 89;
+  string val90 = 90;
+  string val91 = 91;
+  string val92 = 92;
+  string val93 = 93;
+  string val94 = 94;
+  string val95 = 95;
+  string val96 = 96;
+  string val97 = 97;
+  string val98 = 98;
+  string val99 = 99;
+  string val100 = 100;
+  string val101 = 101;
+  string val102 = 102;
+  string val103 = 103;
+  string val104 = 104;
+  string val105 = 105;
+  string val106 = 106;
+  string val107 = 107;
+  string val108 = 108;
+  string val109 = 109;
+  string val110 = 110;
+  string val111 = 111;
+  string val112 = 112;
+  string val113 = 113;
+  string val114 = 114;
+  string val115 = 115;
+  string val116 = 116;
+  string val117 = 117;
+  string val118 = 118;
+  string val119 = 119;
+  string val120 = 120;
+  string val121 = 121;
+  string val122 = 122;
+  string val123 = 123;
+  string val124 = 124;
+  string val125 = 125;
+  string val126 = 126;
+  string val127 = 127;
+  string val128 = 128;
+  string val129 = 129;
+  string val130 = 130;
+  string val131 = 131;
+  string val132 = 132;
+  string val133 = 133;
+  string val134 = 134;
+  string val135 = 135;
+  string val136 = 136;
+  string val137 = 137;
+  string val138 = 138;
+  string val139 = 139;
+  string val140 = 140;
+  string val141 = 141;
+  string val142 = 142;
+  string val143 = 143;
+  string val144 = 144;
+  string val145 = 145;
+  string val146 = 146;
+  string val147 = 147;
+  string val148 = 148;
+  string val149 = 149;
+  string val150 = 150;
+  string val151 = 151;
+  string val152 = 152;
+  string val153 = 153;
+  string val154 = 154;
+  string val155 = 155;
+  string val156 = 156;
+  string val157 = 157;
+  string val158 = 158;
+  string val159 = 159;
+  string val160 = 160;
+  string val161 = 161;
+  string val162 = 162;
+  string val163 = 163;
+  string val164 = 164;
+  string val165 = 165;
+  string val166 = 166;
+  string val167 = 167;
+  string val168 = 168;
+  string val169 = 169;
+  string val170 = 170;
+  string val171 = 171;
+  string val172 = 172;
+  string val173 = 173;
+  string val174 = 174;
+  string val175 = 175;
+  string val176 = 176;
+  string val177 = 177;
+  string val178 = 178;
+  string val179 = 179;
+  string val180 = 180;
+  string val181 = 181;
+  string val182 = 182;
+  string val183 = 183;
+  string val184 = 184;
+  string val185 = 185;
+  string val186 = 186;
+  string val187 = 187;
+  string val188 = 188;
+  string val189 = 189;
+  string val190 = 190;
+  string val191 = 191;
+  string val192 = 192;
+  string val193 = 193;
+  string val194 = 194;
+  string val195 = 195;
+  string val196 = 196;
+  string val197 = 197;
+  string val198 = 198;
+  string val199 = 199;
+  string val200 = 200;
+  string val201 = 201;
+  string val202 = 202;
+  string val203 = 203;
+  string val204 = 204;
+  string val205 = 205;
+  string val206 = 206;
+  string val207 = 207;
+  string val208 = 208;
+  string val209 = 209;
+  string val210 = 210;
+  string val211 = 211;
+  string val212 = 212;
+  string val213 = 213;
+  string val214 = 214;
+  string val215 = 215;
+  string val216 = 216;
+  string val217 = 217;
+  string val218 = 218;
+  string val219 = 219;
+  string val220 = 220;
+  string val221 = 221;
+  string val222 = 222;
+  string val223 = 223;
+  string val224 = 224;
+  string val225 = 225;
+  string val226 = 226;
+  string val227 = 227;
+  string val228 = 228;
+  string val229 = 229;
+  string val230 = 230;
+  string val231 = 231;
+  string val232 = 232;
+  string val233 = 233;
+  string val234 = 234;
+  string val235 = 235;
+  string val236 = 236;
+  string val237 = 237;
+  string val238 = 238;
+  string val239 = 239;
+  string val240 = 240;
+  string val241 = 241;
+  string val242 = 242;
+  string val243 = 243;
+  string val244 = 244;
+  string val245 = 245;
+  string val246 = 246;
+  string val247 = 247;
+  string val248 = 248;
+  string val249 = 249;
+  string val250 = 250;
+  string val251 = 251;
+  string val252 = 252;
+  string val253 = 253;
+  string val254 = 254;
+  string val255 = 255;
+  string val256 = 256;
+  string val257 = 257;
+  string val258 = 258;
+  string val259 = 259;
+  string val260 = 260;
+  string val261 = 261;
+  string val262 = 262;
+  string val263 = 263;
+  string val264 = 264;
+  string val265 = 265;
+  string val266 = 266;
+  string val267 = 267;
+  string val268 = 268;
+  string val269 = 269;
+  string val270 = 270;
+  string val271 = 271;
+  string val272 = 272;
+  string val273 = 273;
+  string val274 = 274;
+  string val275 = 275;
+  string val276 = 276;
+  string val277 = 277;
+  string val278 = 278;
+  string val279 = 279;
+  string val280 = 280;
+  string val281 = 281;
+  string val282 = 282;
+  string val283 = 283;
+  string val284 = 284;
+  string val285 = 285;
+  string val286 = 286;
+  string val287 = 287;
+  string val288 = 288;
+  string val289 = 289;
+  string val290 = 290;
+  string val291 = 291;
+  string val292 = 292;
+  string val293 = 293;
+  string val294 = 294;
+  string val295 = 295;
+  string val296 = 296;
+  string val297 = 297;
+  string val298 = 298;
+  string val299 = 299;
+  string val300 = 300;
+  string val301 = 301;
+  string val302 = 302;
+  string val303 = 303;
+  string val304 = 304;
+  string val305 = 305;
+  string val306 = 306;
+  string val307 = 307;
+  string val308 = 308;
+  string val309 = 309;
+  string val310 = 310;
+  string val311 = 311;
+  string val312 = 312;
+  string val313 = 313;
+  string val314 = 314;
+  string val315 = 315;
+  string val316 = 316;
+  string val317 = 317;
+  string val318 = 318;
+  string val319 = 319;
+  string val320 = 320;
+  string val321 = 321;
+  string val322 = 322;
+  string val323 = 323;
+  string val324 = 324;
+  string val325 = 325;
+  string val326 = 326;
+  string val327 = 327;
+  string val328 = 328;
+  string val329 = 329;
+  string val330 = 330;
+  string val331 = 331;
+  string val332 = 332;
+  string val333 = 333;
+  string val334 = 334;
+  string val335 = 335;
+  string val336 = 336;
+  string val337 = 337;
+  string val338 = 338;
+  string val339 = 339;
+  string val340 = 340;
+  string val341 = 341;
+  string val342 = 342;
+  string val343 = 343;
+  string val344 = 344;
+  string val345 = 345;
+  string val346 = 346;
+  string val347 = 347;
+  string val348 = 348;
+  string val349 = 349;
+  string val350 = 350;
+  string val351 = 351;
+  string val352 = 352;
+  string val353 = 353;
+  string val354 = 354;
+  string val355 = 355;
+  string val356 = 356;
+  string val357 = 357;
+  string val358 = 358;
+  string val359 = 359;
+  string val360 = 360;
+  string val361 = 361;
+  string val362 = 362;
+  string val363 = 363;
+  string val364 = 364;
+  string val365 = 365;
+  string val366 = 366;
+  string val367 = 367;
+  string val368 = 368;
+  string val369 = 369;
+  string val370 = 370;
+  string val371 = 371;
+  string val372 = 372;
+  string val373 = 373;
+  string val374 = 374;
+  string val375 = 375;
+  string val376 = 376;
+  string val377 = 377;
+  string val378 = 378;
+  string val379 = 379;
+  string val380 = 380;
+  string val381 = 381;
+  string val382 = 382;
+  string val383 = 383;
+  string val384 = 384;
+  string val385 = 385;
+  string val386 = 386;
+  string val387 = 387;
+  string val388 = 388;
+  string val389 = 389;
+  string val390 = 390;
+  string val391 = 391;
+  string val392 = 392;
+  string val393 = 393;
+  string val394 = 394;
+  string val395 = 395;
+  string val396 = 396;
+  string val397 = 397;
+  string val398 = 398;
+  string val399 = 399;
+  string val400 = 400;
+  string val401 = 401;
+  string val402 = 402;
+  string val403 = 403;
+  string val404 = 404;
+  string val405 = 405;
+  string val406 = 406;
+  string val407 = 407;
+  string val408 = 408;
+  string val409 = 409;
+  string val410 = 410;
+  string val411 = 411;
+  string val412 = 412;
+  string val413 = 413;
+  string val414 = 414;
+  string val415 = 415;
+  string val416 = 416;
+  string val417 = 417;
+  string val418 = 418;
+  string val419 = 419;
+  string val420 = 420;
+  string val421 = 421;
+  string val422 = 422;
+  string val423 = 423;
+  string val424 = 424;
+  string val425 = 425;
+  string val426 = 426;
+  string val427 = 427;
+  string val428 = 428;
+  string val429 = 429;
+  string val430 = 430;
+  string val431 = 431;
+  string val432 = 432;
+  string val433 = 433;
+  string val434 = 434;
+  string val435 = 435;
+  string val436 = 436;
+  string val437 = 437;
+  string val438 = 438;
+  string val439 = 439;
+  string val440 = 440;
+  string val441 = 441;
+  string val442 = 442;
+  string val443 = 443;
+  string val444 = 444;
+  string val445 = 445;
+  string val446 = 446;
+  string val447 = 447;
+  string val448 = 448;
+  string val449 = 449;
+  string val450 = 450;
+  string val451 = 451;
+  string val452 = 452;
+  string val453 = 453;
+  string val454 = 454;
+  string val455 = 455;
+  string val456 = 456;
+  string val457 = 457;
+  string val458 = 458;
+  string val459 = 459;
+  string val460 = 460;
+  string val461 = 461;
+  string val462 = 462;
+  string val463 = 463;
+  string val464 = 464;
+  string val465 = 465;
+  string val466 = 466;
+  string val467 = 467;
+  string val468 = 468;
+  string val469 = 469;
+  string val470 = 470;
+  string val471 = 471;
+  string val472 = 472;
+  string val473 = 473;
+  string val474 = 474;
+  string val475 = 475;
+  string val476 = 476;
+  string val477 = 477;
+  string val478 = 478;
+  string val479 = 479;
+  string val480 = 480;
+  string val481 = 481;
+  string val482 = 482;
+  string val483 = 483;
+  string val484 = 484;
+  string val485 = 485;
+  string val486 = 486;
+  string val487 = 487;
+  string val488 = 488;
+  string val489 = 489;
+  string val490 = 490;
+  string val491 = 491;
+  string val492 = 492;
+  string val493 = 493;
+  string val494 = 494;
+  string val495 = 495;
+  string val496 = 496;
+  string val497 = 497;
+  string val498 = 498;
+  string val499 = 499;
+  string val500 = 500;
+  string val501 = 501;
+  string val502 = 502;
+  string val503 = 503;
+  string val504 = 504;
+  string val505 = 505;
+  string val506 = 506;
+  string val507 = 507;
+  string val508 = 508;
+  string val509 = 509;
+  string val510 = 510;
+  string val511 = 511;
+  string val512 = 512;
+  string val513 = 513;
+  string val514 = 514;
+  string val515 = 515;
+  string val516 = 516;
+  string val517 = 517;
+  string val518 = 518;
+  string val519 = 519;
+  string val520 = 520;
+  string val521 = 521;
+  string val522 = 522;
+  string val523 = 523;
+  string val524 = 524;
+  string val525 = 525;
+  string val526 = 526;
+  string val527 = 527;
+  string val528 = 528;
+  string val529 = 529;
+  string val530 = 530;
+  string val531 = 531;
+  string val532 = 532;
+  string val533 = 533;
+  string val534 = 534;
+  string val535 = 535;
+  string val536 = 536;
+  string val537 = 537;
+  string val538 = 538;
+  string val539 = 539;
+  string val540 = 540;
+  string val541 = 541;
+  string val542 = 542;
+  string val543 = 543;
+  string val544 = 544;
+  string val545 = 545;
+  string val546 = 546;
+  string val547 = 547;
+  string val548 = 548;
+  string val549 = 549;
+  string val550 = 550;
+  string val551 = 551;
+  string val552 = 552;
+  string val553 = 553;
+  string val554 = 554;
+  string val555 = 555;
+  string val556 = 556;
+  string val557 = 557;
+  string val558 = 558;
+  string val559 = 559;
+  string val560 = 560;
+  string val561 = 561;
+  string val562 = 562;
+  string val563 = 563;
+  string val564 = 564;
+  string val565 = 565;
+  string val566 = 566;
+  string val567 = 567;
+  string val568 = 568;
+  string val569 = 569;
+  string val570 = 570;
+  string val571 = 571;
+  string val572 = 572;
+  string val573 = 573;
+  string val574 = 574;
+  string val575 = 575;
+  string val576 = 576;
+  string val577 = 577;
+  string val578 = 578;
+  string val579 = 579;
+  string val580 = 580;
+  string val581 = 581;
+  string val582 = 582;
+  string val583 = 583;
+  string val584 = 584;
+  string val585 = 585;
+  string val586 = 586;
+  string val587 = 587;
+  string val588 = 588;
+  string val589 = 589;
+  string val590 = 590;
+  string val591 = 591;
+  string val592 = 592;
+  string val593 = 593;
+  string val594 = 594;
+  string val595 = 595;
+  string val596 = 596;
+  string val597 = 597;
+  string val598 = 598;
+  string val599 = 599;
+  string val600 = 600;
+}
+