[pull] main from fern-api:main

fern-changes-yml.schema.json

@@ -18,6 +18,10 @@
                 "type": {
                     "$ref": "#/definitions/ChangelogType",
                     "description": "Type of change determines version bump: fix/chore (patch), feat/internal (minor), break (major)"
+                },
+                "pre-release": {
+                    "$ref": "#/definitions/PreReleaseTag",
+                    "description": "Optional pre-release tag. When set, the release version includes this suffix (e.g., 1.2.0-rc.0)."
                 }
             },
             "required": [
@@ -37,6 +41,16 @@
             ],
             "title": "Changelog Type",
             "description": "The type of change: fix/chore → patch, feat/internal → minor, break → major"
+        },
+        "PreReleaseTag": {
+            "type": "string",
+            "enum": [
+                "alpha",
+                "beta",
+                "rc"
+            ],
+            "title": "Pre-Release Tag",
+            "description": "Pre-release identifier appended to the version (e.g., rc → 1.2.0-rc.0)"
         }
     }
 }

generators/csharp/sdk/changes/unreleased/.template.yml

@@ -6,3 +6,4 @@
     Brief description of your change.
     You can use multiple lines for longer descriptions.
   type: feat  # Options: fix/chore (patch), feat/internal (minor), break (major)
+  # pre-release: rc  # Optional: alpha, beta, or rc (e.g., produces 1.2.0-rc.0)

generators/go-v2/dynamic-snippets/src/context/DynamicSnippetsGeneratorContext.ts

@@ -1,6 +1,7 @@
 import {
     AbstractDynamicSnippetsGeneratorContext,
-    type FernGeneratorExec
+    type FernGeneratorExec,
+    getSdkVersion
 } from "@fern-api/browser-compatible-base-generator";
 import { assertNever } from "@fern-api/core-utils";
 import type { FernIr } from "@fern-api/dynamic-ir-sdk";
@@ -214,14 +215,16 @@ export class DynamicSnippetsGeneratorContext extends AbstractDynamicSnippetsGene
         if (publishInfo.type !== "go") {
             return config;
         }
+        // Prefer --version flag over IR's publish version (which may be the generator version, not SDK version).
+        const originalVersion = getSdkVersion(config);
         return {
             ...config,
             customConfig: generatorConfig.customConfig ?? config.customConfig,
             output: {
                 ...config.output,
                 mode: {
                     type: "github",
-                    version: publishInfo.version,
+                    version: originalVersion ?? publishInfo.version,
                     repoUrl: publishInfo.repoUrl
                 } as FernGeneratorExec.OutputMode
             }

generators/go/model/Dockerfile

@@ -1,6 +1,6 @@
 FROM node:22.12-alpine3.20 AS node
 
-FROM golang:1.23.8-alpine3.20
+FROM golang:1.26.2-alpine3.23
 
 ENV YARN_CACHE_FOLDER=/.yarn
 

generators/go/sdk/Dockerfile

@@ -8,7 +8,7 @@ RUN git config --global user.email "115122769+fern-api[bot]@users.noreply.github
 COPY generators/go-v2/sdk/dist/ /dist/
 
 # Stage 2: Final Go image
-FROM golang:1.23.8-alpine3.20
+FROM golang:1.26.2-alpine3.23
 
 WORKDIR /workspace
 

generators/go/sdk/changes/1.34.4/fix-dynamic-snippets-version-suffix.yml

@@ -0,0 +1,5 @@
+- summary: |
+    Fix dynamic snippets using the generator version instead of the SDK version
+    for resolving Go import paths, which caused incorrect major version suffixes
+    in wire test imports and broke go mod tidy.
+  type: fix

generators/go/sdk/changes/1.34.5/bump-go-toolchain-to-1.26.2.yml

@@ -0,0 +1,8 @@
+# yaml-language-server: $schema=../../../../../fern-changes-yml.schema.json
+
+- summary: |
+    Bump the Go toolchain in the generator Docker image from 1.23.8 to 1.26.2
+    (alpine3.23). This unblocks `go mod tidy` for generated SDKs whose modules
+    (or transitive dependencies) require a newer Go version, which previously
+    failed with `go.mod requires go >= X (running go 1.23.8; GOTOOLCHAIN=local)`.
+  type: fix

generators/go/sdk/changes/unreleased/.template.yml

@@ -6,3 +6,4 @@
     Brief description of your change.
     You can use multiple lines for longer descriptions.
   type: feat  # Options: fix/chore (patch), feat/internal (minor), break (major)
+  # pre-release: rc  # Optional: alpha, beta, or rc (e.g., produces 1.2.0-rc.0)

generators/go/sdk/versions.yml

@@ -1,4 +1,23 @@
 # yaml-language-server: $schema=../../../fern-versions-yml.schema.json
+- version: 1.34.5
+  changelogEntry:
+    - summary: |
+        Bump the Go toolchain in the generator Docker image from 1.23.8 to 1.26.2
+        (alpine3.23). This unblocks `go mod tidy` for generated SDKs whose modules
+        (or transitive dependencies) require a newer Go version, which previously
+        failed with `go.mod requires go >= X (running go 1.23.8; GOTOOLCHAIN=local)`.
+      type: fix
+  createdAt: "2026-04-15"
+  irVersion: 66
+- version: 1.34.4
+  changelogEntry:
+    - summary: |
+        Fix dynamic snippets using the generator version instead of the SDK version
+        for resolving Go import paths, which caused incorrect major version suffixes
+        in wire test imports and broke go mod tidy.
+      type: fix
+  createdAt: "2026-04-15"
+  irVersion: 66
 - version: 1.34.3
   changelogEntry:
     - summary: |

generators/java-v2/dynamic-snippets/src/context/DynamicTypeLiteralMapper.ts

@@ -321,7 +321,8 @@ export class DynamicTypeLiteralMapper {
             case "discriminatedUnion":
                 return this.convertDiscriminatedUnion({
                     discriminatedUnion: named,
-                    value
+                    value,
+                    as
                 });
             case "enum":
                 return this.convertEnum({ enum_: named, value });
@@ -330,18 +331,20 @@ export class DynamicTypeLiteralMapper {
             case "undiscriminatedUnion":
                 // Don't pass inUndiscriminatedUnion here - we're AT the undiscriminated union level,
                 // not within it. The flag should only apply to the variants within the union.
-                return this.convertUndiscriminatedUnion({ undiscriminatedUnion: named, value });
+                return this.convertUndiscriminatedUnion({ undiscriminatedUnion: named, value, as });
             default:
                 assertNever(named);
         }
     }
 
     private convertDiscriminatedUnion({
         discriminatedUnion,
-        value
+        value,
+        as
     }: {
         discriminatedUnion: FernIr.dynamic.DiscriminatedUnionType;
         value: unknown;
+        as?: DynamicTypeLiteralMapper.ConvertedAs;
     }): java.TypeLiteral {
         const classReference = this.context.getJavaClassReferenceFromDeclaration({
             declaration: discriminatedUnion.declaration
@@ -366,7 +369,7 @@ export class DynamicTypeLiteralMapper {
                     java.invokeMethod({
                         on: classReference,
                         method: this.context.getPropertyName(unionVariant.discriminantValue.name),
-                        arguments_: [this.convertNamed({ named, value: discriminatedUnionTypeInstance.value })]
+                        arguments_: [this.convertNamed({ named, value: discriminatedUnionTypeInstance.value, as })]
                     })
                 );
             }
@@ -386,7 +389,8 @@ export class DynamicTypeLiteralMapper {
                             arguments_: [
                                 this.convert({
                                     typeReference: unionVariant.typeReference,
-                                    value: record[propertyKey]
+                                    value: record[propertyKey],
+                                    as
                                 })
                             ]
                         })
@@ -646,14 +650,17 @@ export class DynamicTypeLiteralMapper {
 
     private convertUndiscriminatedUnion({
         undiscriminatedUnion,
-        value
+        value,
+        as
     }: {
         undiscriminatedUnion: FernIr.dynamic.UndiscriminatedUnionType;
         value: unknown;
+        as?: DynamicTypeLiteralMapper.ConvertedAs;
     }): java.TypeLiteral {
         const result = this.findMatchingUndiscriminatedUnionType({
             undiscriminatedUnion,
-            value
+            value,
+            as
         });
         if (result == null) {
             return java.TypeLiteral.nop();
@@ -686,17 +693,20 @@ export class DynamicTypeLiteralMapper {
 
     private findMatchingUndiscriminatedUnionType({
         undiscriminatedUnion,
-        value
+        value,
+        as
     }: {
         undiscriminatedUnion: FernIr.dynamic.UndiscriminatedUnionType;
         value: unknown;
+        as?: DynamicTypeLiteralMapper.ConvertedAs;
     }): { valueTypeReference: FernIr.dynamic.TypeReference; typeInstantiation: java.TypeLiteral } | undefined {
         for (const typeReference of undiscriminatedUnion.types) {
             const errorsBefore = this.context.errors.size();
             try {
                 const typeInstantiation = this.convert({
                     typeReference,
                     value,
+                    as,
                     inUndiscriminatedUnion: true
                 });
 

generators/java-v2/sdk/src/sdk-wire-tests/builders/TestClassBuilder.ts

@@ -139,7 +139,8 @@ export class TestClassBuilder {
         writer.indent();
         writer.writeLine("java.util.Map.Entry<String, JsonNode> entry = iter.next();");
         writer.writeLine("JsonNode actualValue = actual.get(entry.getKey());");
-        writer.writeLine("if (actualValue == null || !jsonEquals(entry.getValue(), actualValue)) return false;");
+        writer.writeLine("if (actualValue == null) { if (!entry.getValue().isNull()) return false; }");
+        writer.writeLine("else if (!jsonEquals(entry.getValue(), actualValue)) return false;");
         writer.dedent();
         writer.writeLine("}");
         writer.writeLine("return true;");

generators/java-v2/sdk/src/sdk-wire-tests/builders/TestMethodBuilder.ts

@@ -83,12 +83,15 @@ export class TestMethodBuilder {
             const rawResponseJson = testExample.response.body;
             const responseStatusCode = testExample.response.statusCode;
 
-            // Convert RFC 2822 dates to ISO 8601 in the response JSON BEFORE using it for both
-            // the mock response body (served by MockWebServer) and the expected response assertion.
-            // Jackson's JavaTimeModule expects ISO 8601 for OffsetDateTime fields typed as "dateTime";
-            // RFC 2822 dates would cause DateTimeParseException during deserialization.
+            // Normalize dates in the response JSON to match Jackson's round-trip output:
+            // - Convert RFC 2822 dates to ISO 8601 (Jackson expects ISO for OffsetDateTime)
+            // - Append "Z" to timezone-less datetimes (DateTimeDeserializer defaults to UTC)
             const expectedResponseJson = rawResponseJson
-                ? (this.convertRfc2822DatesToIso8601(rawResponseJson) as typeof rawResponseJson)
+                ? (this.transformJsonStrings(rawResponseJson, (s) => {
+                      const converted = this.tryConvertRfc2822Date(s);
+                      // Append Z to timezone-less ISO 8601 datetimes
+                      return converted.replace(/^(\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}(?:\.\d+)?)$/, "$1Z");
+                  }) as typeof rawResponseJson)
                 : rawResponseJson;
 
             const mockResponseBody = expectedResponseJson
@@ -309,22 +312,19 @@ export class TestMethodBuilder {
     }
 
     /**
-     * Recursively converts RFC 2822 date strings to ISO 8601 format with Z suffix
-     * in JSON data. This is needed because Jackson's JavaTimeModule serializes
-     * OffsetDateTime as ISO 8601 (e.g. "2015-07-30T20:00:00Z"), but the IR example
-     * data may contain RFC 2822 dates (e.g. "Thu, 30 Jul 2015 20:00:00 +0000").
+     * Recursively applies a string transform to all string values in a JSON structure.
      */
-    private convertRfc2822DatesToIso8601(data: unknown): unknown {
+    private transformJsonStrings(data: unknown, transform: (s: string) => string): unknown {
         if (typeof data === "string") {
-            return this.tryConvertRfc2822Date(data);
+            return transform(data);
         }
         if (Array.isArray(data)) {
-            return data.map((item) => this.convertRfc2822DatesToIso8601(item));
+            return data.map((item) => this.transformJsonStrings(item, transform));
         }
         if (typeof data === "object" && data !== null) {
             const result: Record<string, unknown> = {};
             for (const [key, value] of Object.entries(data)) {
-                result[key] = this.convertRfc2822DatesToIso8601(value);
+                result[key] = this.transformJsonStrings(value, transform);
             }
             return result;
         }

generators/java/generator-utils/src/main/java/com/fern/java/generators/UndiscriminatedUnionGenerator.java

@@ -583,42 +583,51 @@ private TypeSpec getDeserializer() {
                 .addAnnotation(ClassName.get("", "java.lang.Override"))
                 .addStatement(
                         "$T $L = $L.readValueAs($T.class)", Object.class, VALUE_FIELD_SPEC.name, "p", Object.class);
+        // Process primitive instanceof checks first — they are exact type matches.
+        // convertValue branches (used for non-primitives) can do lossy coercion
+        // (e.g., Integer → String), so they must come after primitives to avoid
+        // capturing values meant for a more specific primitive variant.
         for (int i = 0; i < membersWithoutLiterals.size(); ++i) {
             UndiscriminatedUnionMember member = membersWithoutLiterals.get(i);
-
             TypeName typeName = memberTypeNames.get(member);
             if (typeName.isPrimitive() || typeName.isBoxedPrimitive()) {
                 deserializeMethod
                         .beginControlFlow("if ($L instanceof $T)", VALUE_FIELD_SPEC.name, typeName.box())
                         .addStatement(
                                 "return $L(($T) $L)", STATIC_FACTORY_METHOD_NAME, typeName.box(), VALUE_FIELD_SPEC.name)
                         .endControlFlow();
+            }
+        }
+        for (int i = 0; i < membersWithoutLiterals.size(); ++i) {
+            UndiscriminatedUnionMember member = membersWithoutLiterals.get(i);
+            TypeName typeName = memberTypeNames.get(member);
+            if (typeName.isPrimitive() || typeName.isBoxedPrimitive()) {
+                continue;
+            }
+            if (shouldDeserializeWithTypeReference(member)) {
+                deserializeMethod
+                        .beginControlFlow("try")
+                        .addStatement(
+                                "return $L($T.$N.convertValue($L, new $T() {}))",
+                                getDeConflictedMemberName(member, STATIC_FACTORY_METHOD_NAME),
+                                generatorContext.getPoetClassNameFactory().getObjectMapperClassName(),
+                                ObjectMappersGenerator.JSON_MAPPER_STATIC_FIELD_NAME,
+                                VALUE_FIELD_SPEC.name,
+                                ParameterizedTypeName.get(ClassName.get(TypeReference.class), typeName))
+                        .nextControlFlow("catch($T e)", RuntimeException.class)
+                        .endControlFlow();
             } else {
-                if (shouldDeserializeWithTypeReference(member)) {
-                    deserializeMethod
-                            .beginControlFlow("try")
-                            .addStatement(
-                                    "return $L($T.$N.convertValue($L, new $T() {}))",
-                                    getDeConflictedMemberName(member, STATIC_FACTORY_METHOD_NAME),
-                                    generatorContext.getPoetClassNameFactory().getObjectMapperClassName(),
-                                    ObjectMappersGenerator.JSON_MAPPER_STATIC_FIELD_NAME,
-                                    VALUE_FIELD_SPEC.name,
-                                    ParameterizedTypeName.get(ClassName.get(TypeReference.class), typeName))
-                            .nextControlFlow("catch($T e)", RuntimeException.class)
-                            .endControlFlow();
-                } else {
-                    deserializeMethod
-                            .beginControlFlow("try")
-                            .addStatement(
-                                    "return $L($T.$N.convertValue($L, $T.class))",
-                                    getDeConflictedMemberName(member, STATIC_FACTORY_METHOD_NAME),
-                                    generatorContext.getPoetClassNameFactory().getObjectMapperClassName(),
-                                    ObjectMappersGenerator.JSON_MAPPER_STATIC_FIELD_NAME,
-                                    VALUE_FIELD_SPEC.name,
-                                    typeName)
-                            .nextControlFlow("catch($T e)", RuntimeException.class)
-                            .endControlFlow();
-                }
+                deserializeMethod
+                        .beginControlFlow("try")
+                        .addStatement(
+                                "return $L($T.$N.convertValue($L, $T.class))",
+                                getDeConflictedMemberName(member, STATIC_FACTORY_METHOD_NAME),
+                                generatorContext.getPoetClassNameFactory().getObjectMapperClassName(),
+                                ObjectMappersGenerator.JSON_MAPPER_STATIC_FIELD_NAME,
+                                VALUE_FIELD_SPEC.name,
+                                typeName)
+                        .nextControlFlow("catch($T e)", RuntimeException.class)
+                        .endControlFlow();
             }
         }
         deserializeMethod.addStatement("throw new $T(p, $S)", JsonParseException.class, "Failed to deserialize");

generators/java/sdk/Dockerfile

@@ -53,6 +53,10 @@ RUN rm -f /opt/gradle/lib/jackson-core-*.jar && \
 # CVE-2025-14819, CVE-2025-15079, CVE-2025-15224), alsa-lib (CVE-2026-25068),
 # expat (CVE-2026-25210), openssh/openssh-clients (CVE-2025-61984, CVE-2025-61985)
 # Security update 2026-03-30: add freetype (CVE-2026-23865, ALAS2023-2026-1486)
+# Security update 2026-04-15: add python3/python3-libs (ALAS2023-2026-1583,
+# CVE-2025-11468, CVE-2025-15282, CVE-2026-0672, CVE-2026-0865, CVE-2026-1299,
+# CVE-2026-2297, CVE-2026-4224, CVE-2026-4519),
+# libnghttp2 (ALAS2023-2026-1542, CVE-2026-27135)
 RUN dnf --releasever=latest update -y \
     openssl-fips-provider-latest \
     openssl-libs \
@@ -69,7 +73,10 @@ RUN dnf --releasever=latest update -y \
     expat \
     openssh \
     openssh-clients \
-    freetype && \
+    freetype \
+    python3 \
+    python3-libs \
+    libnghttp2 && \
     dnf remove -y git-lfs wget || true && \
     dnf clean all && \
     rm -rf /var/cache/dnf

generators/java/sdk/changes/4.2.0/fix-container-vulnerabilities-2026-04-15.yml

@@ -0,0 +1,7 @@
+# yaml-language-server: $schema=../../../../../fern-changes-yml.schema.json
+
+- summary: |
+    Fix 3 high container vulnerabilities: update python3/python3-libs to
+    3.9.25-1.amzn2023.0.4 (ALAS2023-2026-1583) and libnghttp2 to
+    1.59.0-3.amzn2023.0.2 (ALAS2023-2026-1542, CVE-2026-27135).
+  type: chore

generators/java/sdk/changes/unreleased/.template.yml

@@ -6,3 +6,4 @@
     Brief description of your change.
     You can use multiple lines for longer descriptions.
   type: feat  # Options: fix/chore (patch), feat/internal (minor), break (major)
+  # pre-release: rc  # Optional: alpha, beta, or rc (e.g., produces 1.2.0-rc.0)