Attempt to allocate Buffer larger than maximum size

I'm getting the error:

RangeError: Attempt to allocate Buffer larger than maximum size: 0x3fffffff bytes
    at new Buffer (buffer.js:71:11)
    at Function.Buffer.concat (buffer.js:211:16)
    at BufferOutStream.exports.BufferOutStream.BufferOutStream.data (/usr/local/lib/node_modules/keybase/node_modules/iced-spawn/lib/stream.js:102:21)
    at /usr/local/lib/node_modules/keybase/node_modules/iced-spawn/lib/cmd.js:484:32
    at Deferrals.exports.Deferrals.Deferrals._call (/usr/local/lib/node_modules/keybase/node_modules/iced-runtime/lib/runtime.js:86:16)
    at /usr/local/lib/node_modules/keybase/node_modules/iced-runtime/lib/runtime.js:98:26
    at exports.trampoline.trampoline (/usr/local/lib/node_modules/keybase/node_modules/iced-runtime/lib/runtime.js:64:14)
    at Deferrals.exports.Deferrals.Deferrals._fulfill (/usr/local/lib/node_modules/keybase/node_modules/iced-runtime/lib/runtime.js:96:16)
    at ret (/usr/local/lib/node_modules/keybase/node_modules/iced-runtime/lib/runtime.js:29:18)
    at SpawnEngine.BaseEngine._maybe_call_callback (/usr/local/lib/node_modules/keybase/node_modules/iced-spawn/lib/cmd.js:57:16)

when I try to decrypt a 950mb file.

Start with the stack trace locations in iced-spawn/lib/stream.js and iced-spawn/lib/cmd.js, then inspect how Buffer.concat is reached during decryption. Reproduce the failure with the reported 950 MB file if available. Done means decrypting that file no longer raises the maximum-buffer-size error.