Here's the whole error:

[qtp1816737170-28] ERROR com.biffweb.impl.middleware - Exception while handling request
java.lang.NullPointerException
	at com.biffweb.impl.auth$send_code_BANG_.invokeStatic(auth.clj:107)
	at com.biffweb.impl.auth$send_code_BANG_.invoke(auth.clj:92)
	at com.biffweb.impl.auth$send_code_handler.invokeStatic(auth.clj:167)
	at com.biffweb.impl.auth$send_code_handler.invoke(auth.clj:162)
	at com.biffweb.impl.auth$wrap_options$fn__23761.invoke(auth.clj:241)
	at com.d1kh.middleware$wrap_hx_vals_convert$fn__44362.invoke(middleware.clj:69)
	at com.biffweb.impl.middleware$wrap_render_rum$fn__25751.invoke(middleware.clj:36)
	at com.biffweb.impl.middleware$wrap_anti_forgery_websockets$fn__25744.invoke(middleware.clj:32)
	at ring.middleware.anti_forgery$wrap_anti_forgery$fn__22609.invoke(anti_forgery.clj:94)
	at ring.middleware.session$wrap_session$fn__25209.invoke(session.clj:108)
	at com.biffweb.impl.middleware$wrap_session$fn__25807.invoke(middleware.clj:141)
	at muuntaja.middleware$wrap_params$fn__24783.invoke(middleware.clj:52)
	at muuntaja.middleware$wrap_format$fn__24787.invoke(middleware.clj:73)
	at ring.middleware.keyword_params$wrap_keyword_params$fn__25255.invoke(keyword_params.clj:53)
	at ring.middleware.nested_params$wrap_nested_params$fn__25313.invoke(nested_params.clj:89)
	at ring.middleware.multipart_params$wrap_multipart_params$fn__25445.invoke(multipart_params.clj:171)
	at ring.middleware.params$wrap_params$fn__25472.invoke(params.clj:75)
	at ring.middleware.cookies$wrap_cookies$fn__25088.invoke(cookies.clj:214)
	at ring.middleware.absolute_redirects$wrap_absolute_redirects$fn__25626.invoke(absolute_redirects.clj:47)
	at ring.middleware.content_type$wrap_content_type$fn__24820.invoke(content_type.clj:34)
	at ring.middleware.default_charset$wrap_default_charset$fn__25598.invoke(default_charset.clj:31)
	at ring.middleware.not_modified$wrap_not_modified$fn__25574.invoke(not_modified.clj:61)
	at ring.middleware.x_headers$wrap_x_header$fn__24851.invoke(x_headers.clj:22)
	at ring.middleware.x_headers$wrap_x_header$fn__24851.invoke(x_headers.clj:22)
	at ring.middleware.x_headers$wrap_x_header$fn__24851.invoke(x_headers.clj:22)
	at reitit.ring$ring_handler$fn__21688.invoke(ring.cljc:329)
	at clojure.lang.AFn.applyToHelper(AFn.java:154)
	at clojure.lang.AFn.applyTo(AFn.java:144)
	at clojure.lang.AFunction$1.doInvoke(AFunction.java:31)
	at clojure.lang.RestFn.invoke(RestFn.java:408)
	at com.biffweb.impl.middleware$wrap_https_scheme$fn__25801.invoke(middleware.clj:111)
	at com.biffweb.impl.middleware$wrap_resource$fn__25767.invoke(middleware.clj:62)
	at com.biffweb.impl.middleware$wrap_internal_error$fn__25784.invoke(middleware.clj:80)
	at com.biffweb.impl.middleware$wrap_ssl$fn__25812.invoke(middleware.clj:156)
	at com.biffweb.impl.middleware$wrap_log_requests$fn__25795.invoke(middleware.clj:97)
	at clojure.lang.Var.invoke(Var.java:384)
	at com.biffweb.impl.middleware$use_wrap_ctx$fn__25822.invoke(middleware.clj:188)
	at ring.adapter.jetty9$proxy_handler$fn__22256.invoke(jetty9.clj:75)
	at ring.adapter.jetty9.proxy$org.eclipse.jetty.servlet.ServletHandler$ff19274a.doHandle(Unknown Source)
	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:221)
	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1378)
	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:176)
	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:463)
	at ring.adapter.jetty9.proxy$org.eclipse.jetty.servlet.ServletHandler$ff19274a.doScope(Unknown Source)
	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:174)
	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1300)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:129)
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:122)
	at org.eclipse.jetty.server.Server.handle(Server.java:562)
	at org.eclipse.jetty.server.HttpChannel.lambda$handle$0(HttpChannel.java:418)
	at org.eclipse.jetty.server.HttpChannel.dispatch(HttpChannel.java:675)
	at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:410)
	at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:282)
	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:319)
	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:100)
	at org.eclipse.jetty.io.SocketChannelEndPoint$1.run(SocketChannelEndPoint.java:101)
	at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.runTask(AdaptiveExecutionStrategy.java:412)
	at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.consumeTask(AdaptiveExecutionStrategy.java:381)
	at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.tryProduce(AdaptiveExecutionStrategy.java:268)
	at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.lambda$new$0(AdaptiveExecutionStrategy.java:138)
	at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:407)
	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:894)
	at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:1038)
	at java.base/java.lang.Thread.run(Thread.java:829)
[qtp1816737170-28] INFO com.biffweb.impl.middleware -  51ms 500 post /auth/send-code

For what it's worth, starting a whole new project works fine. So I figure it's got to be something I'm missing.

This is the line referenced at the top of the stack trace: https://github.com/jacobobryant/biff/blob/6a5ba0a7a0a052d3ee88adaad645dcddf8bc3876/src/com/biffweb/impl/auth.clj#L107 Looks like send-email is nil. You probably missed this bit: https://github.com/jacobobryant/biff/commit/6a5ba0a7a0a052d3ee88adaad645dcddf8bc3876#diff-dc8d794a683c27486f2b534a9fd84dab78e04d2c68963cd22dc776598320aa82R64 At some point I probably should start doing some argument validation so you get more helpful error messages than NullPointerException 🙂 > built some middleware to redirect folks to the page they wanted when they were prompted with a sign-in I'd be down to add support for this to the auth plugin; probably by sticking a redirect parameter inside the JWT. (Also feel free to stick with your own auth in the mean time if you prefer! As with all parts of Biff, it's idiomatic/recommended to roll your own whenever something that Biff provides doesn't quite do what you want.) > and added some default data to each user document when they first signed up You can do this if you pass in the :biff.auth/new-user-tx option to biff/authentication-plugin. There's a section about that in the https://biffweb.com/docs/api/authentication/--you can copy and paste the default new-user-tx fn and modify as needed. Note that the first param (`ctx`) includes the ring request for the signup form, so you have access to any form parameters if needed.

> Looks like send-email is nil. You probably missed this bit: That was it!

I'm really excited about the new auth stuff. Aside from figuring out how to handle redirecting, it's pretty much doing what I want and I suspect it'll pass my "Will my parents be able to access my website without asking me for customer support every time?" test. And that's golden.

glad to hear it!