diff --git a/build.gradle b/build.gradle
index f22c96926d..0ae95b26ad 100644
--- a/build.gradle
+++ b/build.gradle
@@ -224,6 +224,8 @@ allprojects {
                     force "com.google.guava:guava:${guavaVersion}"
                     // force version for SequenceAnalysis, TargetedMS
                     force "com.google.protobuf:protobuf-java:${googleProtocolBufVersion}"
+                    // force Jakarta Activation API version used by our Angus Activation implementation
+                    force "jakarta.activation:jakarta.activation-api:${jakartaActivationApiVersion}"
                     // force version for accounts, api, query
                     force "javax.validation:validation-api:${validationApiVersion}"
                     // force version for accounts, docker, api, workflow
diff --git a/gradle.properties b/gradle.properties
index 835bea9191..f278c7ce99 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -88,6 +88,7 @@ npmWorkDirectory=.node
 # gradle.properties file to declare these version numbers. Naming
 # convention is <library name>Version camel-cased, i.e. "jacksonVersion".
 
+# The implementation of Jakarta Activation API that we use. Keep in sync with jakartaActivationApiVersion (below).
 angusActivationVersion=2.0.2
 angusMailVersion=2.0.3
 
@@ -197,6 +198,9 @@ jacksonAnnotationsVersion=2.18.1
 jacksonDatabindVersion=2.18.1
 jacksonJaxrsBaseVersion=2.18.1
 
+# The Jakarta Activation API version that Angus Activation implements. Keep in sync with angusActivationVersion (above).
+jakartaActivationApiVersion=2.1.3
+
 jamaVersion=1.0.3
 
 javassistVersion=3.20.0-GA
diff --git a/server/bootstrap/build.gradle b/server/bootstrap/build.gradle
index 7f7c8a101e..c5fcb3e8e3 100644
--- a/server/bootstrap/build.gradle
+++ b/server/bootstrap/build.gradle
@@ -15,14 +15,13 @@ sourceSets {
 }
 
 dependencies
-        {
-            def tomcatVersion = project.apacheTomcatVersion
-
-            implementation "org.apache.tomcat:tomcat-api:${tomcatVersion}"
-            implementation "org.apache.tomcat:tomcat-catalina:${tomcatVersion}"
-            implementation "org.apache.tomcat:tomcat-juli:${tomcatVersion}"
-            implementation "org.apache.tomcat:tomcat-util:${tomcatVersion}"
+{
+    implementation('org.apache.tomcat.embed:tomcat-embed-core') {
+        version {
+            strictly "${apacheTomcatVersion}"
         }
+    }
+}
 
 def JAR_BASE_NAME = "labkeyBootstrap"
 project.jar {
@@ -65,9 +64,6 @@ project.afterEvaluate  {
                     publications('libs')
                 }
             }
-
         }
     }
-}
-
-
+}
\ No newline at end of file
diff --git a/server/embedded/build.gradle b/server/embedded/build.gradle
index adf4e3d143..3c66f3d6cf 100644
--- a/server/embedded/build.gradle
+++ b/server/embedded/build.gradle
@@ -31,15 +31,15 @@ configurations {
 }
 
 configurations.configureEach {
-//    exclude group: 'org.springframework.boot', module: 'spring-boot-starter-logging'
     exclude group: 'ch.qos.logback', module: 'logback-classic'
     exclude group: 'org.apache.logging.log4j', module: 'log4j-to-slf4j'
 }
 
 dependencies {
-    implementation "org.springframework.boot:spring-boot-starter-web:${springBootVersion}"
-    implementation "org.springframework.boot:spring-boot-starter-actuator:${springBootVersion}"
-    implementation "org.springframework.boot:spring-boot-starter-validation:${springBootVersion}"
+    implementation("org.springframework.boot:spring-boot-starter-web:${springBootVersion}") {
+        exclude group: "org.springframework.boot", module: "spring-boot-starter-json" // Not used (?) and pulls in an old version of Jackson
+        exclude group: "jakarta.annotation", module: "jakarta.annotation-api" // Already present in tomcat-annotations-api
+    }
 
     // Allows forcing a Spring Framework version that differs from spring-boot's version (e.g., to address CVEs)
     implementation('org.springframework:spring-web') {
@@ -50,11 +50,6 @@ dependencies {
 
     // Allows forcing a Tomcat version that differs from spring-boot's version (e.g., to address CVEs or regressions,
     // or to test a Tomcat release candidate)
-    implementation('org.apache.tomcat.embed:tomcat-embed-core') {
-        version {
-            strictly "${apacheTomcatVersion}"
-        }
-    }
     implementation('org.apache.tomcat.embed:tomcat-embed-el') {
         version {
             strictly "${apacheTomcatVersion}"
@@ -70,14 +65,11 @@ dependencies {
             strictly "${apacheTomcatVersion}"
         }
     }
-    implementation('org.apache.tomcat:tomcat-jsp-api') {
-        version {
-            strictly "${apacheTomcatVersion}"
-        }
-    }
 
     runtimeOnly "org.apache.tomcat.embed:tomcat-embed-jasper:${apacheTomcatVersion}"
-    runtimeOnly group: "org.apache.tomcat", name: "tomcat-dbcp", version: "${apacheTomcatVersion}"
+    runtimeOnly("org.apache.tomcat:tomcat-dbcp:${apacheTomcatVersion}") {
+        exclude group: "org.apache.tomcat", module: "tomcat-juli"
+    }
     runtimeOnly "org.apache.logging.log4j:log4j-slf4j2-impl:${log4j2Version}"
     implementation "commons-io:commons-io:${commonsIoVersion}"
     implementation "org.apache.logging.log4j:log4j-core:${log4j2Version}"
diff --git a/server/embedded/src/org/labkey/embedded/LabKeyServer.java b/server/embedded/src/org/labkey/embedded/LabKeyServer.java
index 060c020437..db6f1c07e2 100644
--- a/server/embedded/src/org/labkey/embedded/LabKeyServer.java
+++ b/server/embedded/src/org/labkey/embedded/LabKeyServer.java
@@ -1,6 +1,5 @@
 package org.labkey.embedded;
 
-import jakarta.validation.constraints.NotNull;
 import org.apache.catalina.connector.Connector;
 import org.labkey.bootstrap.PipelineBootstrapConfig;
 import org.springframework.boot.Banner;
@@ -405,7 +404,6 @@ public static class ContextProperties
 
         private String webAppLocation;
         private String workDirLocation;
-        @NotNull (message = "Must provide encryptionKey")
         private String encryptionKey;
         private String oldEncryptionKey;
         private String legacyContextPath;
@@ -499,6 +497,8 @@ public void setWorkDirLocation(String workDirLocation)
 
         public String getEncryptionKey()
         {
+            if (null == encryptionKey)
+                throw new RuntimeException("Must provide encryptionKey");
             return encryptionKey;
         }
 
diff --git a/server/embedded/src/org/labkey/embedded/LabKeySpringBootClassLoader.java b/server/embedded/src/org/labkey/embedded/LabKeySpringBootClassLoader.java
index 3a8301817d..4f03b0d404 100644
--- a/server/embedded/src/org/labkey/embedded/LabKeySpringBootClassLoader.java
+++ b/server/embedded/src/org/labkey/embedded/LabKeySpringBootClassLoader.java
@@ -1,6 +1,7 @@
 package org.labkey.embedded;
 
-import org.jboss.logging.Logger;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import org.labkey.bootstrap.LabKeyBootstrapClassLoader;
 
 import java.io.IOException;
@@ -19,7 +20,7 @@
  */
 public class LabKeySpringBootClassLoader extends LabKeyBootstrapClassLoader
 {
-    private static final Logger LOG = Logger.getLogger(LabKeySpringBootClassLoader.class);
+    private static final Logger LOG = LogManager.getLogger(LabKeySpringBootClassLoader.class);
 
     public LabKeySpringBootClassLoader()
     {