diff --git a/src/windows/WslcSDK/wslcsdk.h b/src/windows/WslcSDK/wslcsdk.h
index 2cec8d2cd..2abbbc8b4 100644
--- a/src/windows/WslcSDK/wslcsdk.h
+++ b/src/windows/WslcSDK/wslcsdk.h
@@ -477,7 +477,7 @@ typedef struct WslcImageInfo
     // we should expose this
     CHAR name[WSLC_IMAGE_NAME_LENGTH];
     uint8_t sha256[32];
-    uint64_t sizeBytes;
+    int64_t sizeBytes;
     uint64_t createdUnixTime;
 } WslcImageInfo;
 
diff --git a/src/windows/common/WSLCContainerLauncher.cpp b/src/windows/common/WSLCContainerLauncher.cpp
index 51826ebd4..dc68e69c2 100644
--- a/src/windows/common/WSLCContainerLauncher.cpp
+++ b/src/windows/common/WSLCContainerLauncher.cpp
@@ -129,7 +129,7 @@ void WSLCContainerLauncher::SetDefaultStopSignal(WSLCSignal Signal)
     m_stopSignal = Signal;
 }
 
-void WSLCContainerLauncher::SetShmSize(ULONGLONG ShmSize)
+void WSLCContainerLauncher::SetShmSize(int64_t ShmSize)
 {
     m_shmSize = ShmSize;
 }
diff --git a/src/windows/common/WSLCContainerLauncher.h b/src/windows/common/WSLCContainerLauncher.h
index e31521115..ee52fcd2f 100644
--- a/src/windows/common/WSLCContainerLauncher.h
+++ b/src/windows/common/WSLCContainerLauncher.h
@@ -73,7 +73,7 @@ class WSLCContainerLauncher : private WSLCProcessLauncher
     void SetName(std::string&& Name);
     void SetEntrypoint(std::vector<std::string>&& entrypoint);
     void SetDefaultStopSignal(WSLCSignal Signal);
-    void SetShmSize(ULONGLONG ShmSize);
+    void SetShmSize(int64_t ShmSize);
     void SetContainerFlags(WSLCContainerFlags Flags);
     void SetContainerNetworkName(std::string&& Name);
     void SetHostname(std::string&& Hostname);
@@ -102,7 +102,7 @@ class WSLCContainerLauncher : private WSLCProcessLauncher
     std::string m_containerNetworkName;
     std::vector<std::string> m_entrypoint;
     WSLCSignal m_stopSignal = WSLCSignalNone;
-    ULONGLONG m_shmSize = 0;
+    int64_t m_shmSize = 0;
     WSLCContainerFlags m_containerFlags = WSLCContainerFlagsNone;
     std::string m_hostname;
     std::string m_domainname;
diff --git a/src/windows/inc/docker_schema.h b/src/windows/inc/docker_schema.h
index 916524b0e..ea15bfe79 100644
--- a/src/windows/inc/docker_schema.h
+++ b/src/windows/inc/docker_schema.h
@@ -9,7 +9,8 @@ Module Name:
 Abstract:
 
     JSON schema for the docker API.
-    The documentation for the API can be found at: https://docs.docker.com/reference/api/engine/version/v1.52/#tag/Container
+    Targets the daemon API version bundled with WSLC's dockerd (currently v25.0.3, API v1.44).
+    The documentation for the API can be found at: https://docs.docker.com/reference/api/engine/version/v1.44/#tag/Container
 
 --*/
 
@@ -22,10 +23,9 @@ namespace wsl::windows::common::docker_schema {
 struct CreatedContainer
 {
     std::string Id;
-    std::string Name;
     std::vector<std::string> Warnings;
 
-    NLOHMANN_DEFINE_TYPE_INTRUSIVE(CreatedContainer, Id, Warnings);
+    NLOHMANN_DEFINE_TYPE_INTRUSIVE_WITH_DEFAULT(CreatedContainer, Id, Warnings);
 };
 
 struct ErrorResponse
@@ -83,7 +83,10 @@ struct Volume
     std::string CreatedAt;
     std::optional<std::map<std::string, std::string>> Options;
     std::optional<std::map<std::string, std::string>> Labels;
-    std::optional<std::map<std::string, std::string>> Status;
+    // Docker's wire schema for Status is map[string]any: third-party volume
+    // drivers may set arbitrary JSON values (numbers, bools, objects), not
+    // just strings. Use nlohmann::json so deserialization never throws.
+    std::optional<std::map<std::string, nlohmann::json>> Status;
     std::optional<VolumeUsageData> UsageData;
 
     NLOHMANN_DEFINE_TYPE_INTRUSIVE_WITH_DEFAULT(Volume, Name, Driver, Mountpoint, CreatedAt, Options, Labels, Status, UsageData);
@@ -223,7 +226,9 @@ struct HostConfig
     std::optional<std::vector<std::string>> DnsOptions;
     std::optional<std::vector<std::string>> Binds;
     std::map<std::string, std::string> Tmpfs;
-    std::optional<ULONGLONG> ShmSize;
+    // Docker wire type is int64. 0 means "use daemon default" — same as omitting
+    // the field — so we don't bother with std::optional here.
+    std::int64_t ShmSize{};
     std::optional<std::vector<DeviceMapping>> Devices;
 
     // Per-container resource limits. 0 means "no limit" (Docker default).
@@ -356,7 +361,7 @@ struct Image
     std::string Id;
     std::vector<std::string> RepoTags;
     std::vector<std::string> RepoDigests;
-    uint64_t Size{};
+    int64_t Size{};
     int64_t Created{};
     std::string ParentId;
 
@@ -432,7 +437,7 @@ struct InspectImage
     std::string Variant;
     std::string Os;
     std::string OsVersion;
-    uint64_t Size{};
+    int64_t Size{};
     std::optional<GraphDriverData> GraphDriver;
     std::optional<RootFS> RootFS;
     std::optional<std::map<std::string, std::string>> Metadata;
@@ -455,41 +460,73 @@ struct CreateExec
     bool AttachStdout{};
     bool AttachStderr{};
     bool Tty{};
+    // Docker wire type is *[2]uint64. Sending an empty array on a TTY exec yields
+    // a 0x0 console; the field must be omitted entirely when the caller didn't set it.
     std::vector<ULONG> ConsoleSize;
     std::vector<std::string> Cmd;
     std::vector<std::string> Env;
     std::optional<std::string> User;
     std::string WorkingDir;
     std::optional<std::string> DetachKeys;
-
-    NLOHMANN_DEFINE_TYPE_INTRUSIVE_WITH_DEFAULT(CreateExec, AttachStdin, AttachStdout, AttachStderr, Tty, ConsoleSize, Cmd, Env, WorkingDir, User, DetachKeys);
 };
 
+inline void to_json(nlohmann::json& j, const CreateExec& v)
+{
+    j = nlohmann::json{
+        {"AttachStdin", v.AttachStdin},
+        {"AttachStdout", v.AttachStdout},
+        {"AttachStderr", v.AttachStderr},
+        {"Tty", v.Tty},
+        {"Cmd", v.Cmd},
+        {"Env", v.Env},
+        {"WorkingDir", v.WorkingDir},
+        {"User", v.User},
+        {"DetachKeys", v.DetachKeys},
+    };
+
+    if (!v.ConsoleSize.empty())
+    {
+        j["ConsoleSize"] = v.ConsoleSize;
+    }
+}
+
 struct StartExec
 {
     using TResponse = void;
     bool Tty{};
     bool Detach{};
+    // See CreateExec::ConsoleSize.
     std::vector<ULONG> ConsoleSize;
-
-    NLOHMANN_DEFINE_TYPE_INTRUSIVE_ONLY_SERIALIZE(StartExec, Tty, Detach, ConsoleSize);
 };
 
+inline void to_json(nlohmann::json& j, const StartExec& v)
+{
+    j = nlohmann::json{{"Tty", v.Tty}, {"Detach", v.Detach}};
+
+    if (!v.ConsoleSize.empty())
+    {
+        j["ConsoleSize"] = v.ConsoleSize;
+    }
+}
+
 enum class ContainerState
 {
+    Unknown,
     Created,
     Running,
     Paused,
     Restarting,
     Exited,
     Removing,
-    Dead,
-    Unknown
+    Dead
 };
 
 NLOHMANN_JSON_SERIALIZE_ENUM(
     ContainerState,
     {
+        // Unknown is first so unrecognized strings (or missing field) deserialize to Unknown,
+        // not to whatever the next entry happens to be.
+        {ContainerState::Unknown, nullptr},
         {ContainerState::Created, "created"},
         {ContainerState::Running, "running"},
         {ContainerState::Paused, "paused"},
@@ -580,7 +617,7 @@ struct CreateImageProgress
 };
 
 // Container stats (GET /containers/{id}/stats?stream=false)
-// See: https://docs.docker.com/reference/api/engine/version/v1.52/#tag/Container/operation/ContainerStats
+// See: https://docs.docker.com/reference/api/engine/version/v1.44/#tag/Container/operation/ContainerStats
 
 struct ContainerStatsCpuUsage
 {
diff --git a/src/windows/inc/wslc_schema.h b/src/windows/inc/wslc_schema.h
index f5576391c..3309b6d32 100644
--- a/src/windows/inc/wslc_schema.h
+++ b/src/windows/inc/wslc_schema.h
@@ -136,7 +136,7 @@ struct InspectImage
     std::string Author;
     std::string Architecture;
     std::string Os;
-    uint64_t Size{};
+    int64_t Size{};
     std::optional<std::map<std::string, std::string>> Metadata;
     std::optional<ImageConfig> Config;
 
diff --git a/src/windows/service/inc/wslc.idl b/src/windows/service/inc/wslc.idl
index 2ad3216f8..699e659a8 100644
--- a/src/windows/service/inc/wslc.idl
+++ b/src/windows/service/inc/wslc.idl
@@ -122,7 +122,7 @@ typedef struct _WSLCImageInformation
     char Image[WSLC_MAX_IMAGE_NAME_LENGTH + 1];
     char Hash[256];
     char Digest[256];
-    ULONGLONG Size;
+    LONGLONG Size; // Matches Docker's int64 image size
     LONGLONG Created; // Unix timestamp
     char ParentId[256];
 } WSLCImageInformation;
@@ -301,7 +301,7 @@ typedef struct _WSLCContainerOptions
     WSLCStringArray DnsSearchDomains;
     WSLCStringArray DnsOptions;
 
-    ULONGLONG ShmSize;
+    LONGLONG ShmSize; // Matches Docker's int64 ShmSize; consistent with MemoryBytes/NanoCpus
     WSLCContainerNetwork ContainerNetwork;
     [unique, size_is(TmpfsCount)] const WSLCTmpfsMount* Tmpfs;
     ULONG TmpfsCount;
diff --git a/src/windows/wslc/arguments/ArgumentValidation.cpp b/src/windows/wslc/arguments/ArgumentValidation.cpp
index 28fab0b22..5604d685e 100644
--- a/src/windows/wslc/arguments/ArgumentValidation.cpp
+++ b/src/windows/wslc/arguments/ArgumentValidation.cpp
@@ -248,7 +248,7 @@ void ValidateMemorySize(const std::vector<std::wstring>& values, const std::wstr
     }
 }
 
-ULONGLONG GetMemorySizeFromString(const std::wstring& input, const std::wstring& argName)
+int64_t GetMemorySizeFromString(const std::wstring& input, const std::wstring& argName)
 {
     auto parsed = wsl::shared::string::ParseMemorySize(input.c_str());
     if (!parsed.has_value())
@@ -256,7 +256,7 @@ ULONGLONG GetMemorySizeFromString(const std::wstring& input, const std::wstring&
         throw ArgumentException(Localization::WSLCCLI_InvalidMemorySizeError(argName, input));
     }
 
-    return parsed.value();
+    return static_cast<int64_t>(parsed.value());
 }
 
 } // namespace wsl::windows::wslc::validation
diff --git a/src/windows/wslc/arguments/ArgumentValidation.h b/src/windows/wslc/arguments/ArgumentValidation.h
index 03665f595..e0d66fb58 100644
--- a/src/windows/wslc/arguments/ArgumentValidation.h
+++ b/src/windows/wslc/arguments/ArgumentValidation.h
@@ -63,7 +63,7 @@ void ValidateWSLCSignalFromString(const std::vector<std::wstring>& values, const
 WSLCSignal GetWSLCSignalFromString(const std::wstring& input, const std::wstring& argName = {});
 
 void ValidateMemorySize(const std::vector<std::wstring>& values, const std::wstring& argName);
-ULONGLONG GetMemorySizeFromString(const std::wstring& input, const std::wstring& argName = {});
+int64_t GetMemorySizeFromString(const std::wstring& input, const std::wstring& argName = {});
 
 void ValidateFormatTypeFromString(const std::vector<std::wstring>& values, const std::wstring& argName);
 FormatType GetFormatTypeFromString(const std::wstring& input, const std::wstring& argName = {});
diff --git a/src/windows/wslc/services/ContainerModel.h b/src/windows/wslc/services/ContainerModel.h
index 88dc88a43..47e052788 100644
--- a/src/windows/wslc/services/ContainerModel.h
+++ b/src/windows/wslc/services/ContainerModel.h
@@ -38,7 +38,7 @@ struct ContainerOptions
     bool TTY = false;
     bool PublishAll = false;
     WSLCSignal StopSignal = WSLCSignalNone;
-    std::optional<ULONGLONG> ShmSize{};
+    std::optional<int64_t> ShmSize{};
     bool Gpu = false;
     std::vector<std::string> Ports;
     std::vector<std::wstring> Volumes;
diff --git a/src/windows/wslc/services/ImageModel.h b/src/windows/wslc/services/ImageModel.h
index 1ebb87d03..a32d665b4 100644
--- a/src/windows/wslc/services/ImageModel.h
+++ b/src/windows/wslc/services/ImageModel.h
@@ -23,7 +23,7 @@ struct ImageInformation
     std::optional<std::string> Tag;
     std::string Id;
     LONGLONG Created{};
-    ULONGLONG Size{};
+    int64_t Size{};
 
     NLOHMANN_DEFINE_TYPE_INTRUSIVE_WITH_DEFAULT(ImageInformation, Repository, Tag, Id, Created, Size);
 };
diff --git a/src/windows/wslcsession/WSLCContainer.cpp b/src/windows/wslcsession/WSLCContainer.cpp
index aaa602b00..08d9536ec 100644
--- a/src/windows/wslcsession/WSLCContainer.cpp
+++ b/src/windows/wslcsession/WSLCContainer.cpp
@@ -1413,10 +1413,7 @@ std::unique_ptr<WSLCContainerImpl> WSLCContainerImpl::Create(
         request.HostConfig.Ulimits = std::move(ulimits);
     }
 
-    if (containerOptions.ShmSize > 0)
-    {
-        request.HostConfig.ShmSize = containerOptions.ShmSize;
-    }
+    request.HostConfig.ShmSize = containerOptions.ShmSize;
 
     if (containerOptions.VolumesCount > 0)
     {