RangeError: Invalid string length in flushBackendAsync

[lachrist]

(node:26107) UnhandledPromiseRejectionWarning: RangeError: Invalid string length
    at stringify (<anonymous>)
    at flushBackendAsync (file:///Users/[redacted]/tmp/models/node_modules/@appland/appmap-agent-js/dist/bundles/server.mjs:5202:7)
    at async file:///Users/[redacted]/tmp/models/node_modules/@appland/appmap-agent-js/dist/bundles/server.mjs:5244:7
    at async mainAsync (file:///Users/[redacted]/tmp/models/node_modules/@appland/appmap-agent-js/dist/bundles/server.mjs:5323:3)
(Use `node --trace-warnings ...` to show where the warning was created)
(node:26107) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 2)
(node:26107) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.