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Mike Bannister possibilities

  • AI Life
  • Portland East
  • 20:45 (UTC -04:00)
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Senior Software Engineer (React, Full-stack) @ River

Company Overview

River is constructing "the world's most trusted financial institution to empower people to take ownership of their financial lives through Bitcoin." The organization has secured over $50 million in funding from prominent investors including Goldcrest, Kingsway, Polychain, M13, DG, and Valor. The company demonstrates transparency by publicly sharing financials and proof of reserves.

Role Summary

River seeks a senior engineer comfortable across the full web stack with production system experience at scale. The successful candidate will develop features used daily by clients, working with a tech foundation of Elixir, React, and Postgres.

Hi River team,

The Senior Software Engineer role stands out for pairing React product work with real security and correctness, plus your public proof of reserves and open financials. I am enthusiastic about Bitcoin and your goal of helping people take ownership of their money. I am curious how you split concerns between React and Elixir, how you model custody and transfers, and what guardrails you use for web security in high-risk flows like auth, funding, and withdrawals. I would also love to learn how you validate changes that touch balances and what you publish internally to keep risks visible.

From 2020 to 2025 at Vermont Mutual Insurance, I led the modernization of legacy tools and customer apps into performant React SPAs and drove UI development across teams of 10 to 20 engineers and designers. I partnered closely with design, pushed for UX-first development, and shipped features users praised. I also led a generative AI pilot that evaluated tools, gathered feedback from internal users, and advised on

River Phone Screen Brief — Thu Mar 12, 4:00 PM EDT

Call: 20-min preliminary screen with James Page (Chief Product Officer) via Google Meet Role: Senior Software Engineer (React, Full-stack) Not a coding interview — this is a fit/interest conversation


The Company in 60 Seconds

@possibilities
possibilities / codectl-specification.md
Created March 12, 2026 01:17
codectl: Specification & Design Document

codectl: Specification & Design Document

Carving out codectl's role across two systems — as a standalone repo context generator and as contextctl's codebase intelligence engine.

Sources: contextctl research report, repoprompt reverse engineering bible, knowctl repoprompt topic (40 docs), Codex architecture review, competitive landscape research (Aider, Kit, CatCoder, Sourcegraph Cody, Moderne Prethink).


The Core Insight

@possibilities
possibilities / screenshot-gist.md
Created March 11, 2026 21:34
Screen capture during tmuxctl window ordering fix

Screen Capture - tmuxctl window ordering fix

![screenshot](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAACgAAAAWgCAYAAACSABrfAAABQGlDQ1BJQ0MgUHJvZmlsZQAAGJV9kL9LQlEYhp+bhpANBW1FCEUQWISGtppDBA03K/oxBNfrVYOrHa5Xov+gtaWpuTlocGhpaGssCvoTWhoCl5Lbd7TSivoOL9/De95z+PigD0spNwxUqr6XW1qMbW3vxCJPhIgSYZy0ZddUxjRXJMJn/17Newzdb2f0X7/v/62BglOzpb+Jpmzl+WBMCpsHvtIsYsSToYSPNJc6fKo53+HzdmY9lxW+Fh6yy1ZB+E44nu/xSz1ccev2xwx6+kGnurGm5xGNsUqSBGk5/JGbb+ey7KM4xGOPEmV8YmTEUbg4wstUsZklLpxgTpTS+/25t66nnmFBZBS7Xn4ULndh+LjrTdxA9AKuUsryrK9tGs1wrZhMdDjagP6TIHjZhMg0tB6C4LURBK0zCD3K2+Y7wZpaNzgVpPEAAABWZVhJZk1NACoAAAAIAAGHaQAEAAAAAQAAABoAAAAAAAOShgAHAAAAEgAAAESgAgAEAAAAAQAACgCgAwAEAAAAAQAABaAAAAAAQVNDSUkAAABTY3JlZW5zaG90GeNJIwAAAdhpVFh0WE1MOmNvbS5hZG9iZS54bXAAAAAAADx4OnhtcG1ldGEgeG1sbnM6eD0iYWRvYmU6bnM6bWV0YS8iIHg6eG1wdGs9IlhNUCBDb3JlIDYuMC4wIj4KICAgPHJkZjpSREYgeG1sbnM6cmRmPSJodHRwOi8vd3d3LnczLm9yZy8xOTk5LzAyLzIyLXJkZi1zeW50YXgtbnMjIj4KICAgICAgPHJkZjpEZXNjcmlwdGlvbiByZGY6YWJvdXQ9IiIKICAgICAgICAgICAgeG1sbnM6ZXhpZj0iaHR0cDovL25zLmFkb2JlLmNvbS9l

@possibilities
possibilities / geminctl-example.md
Created March 11, 2026 16:03
geminctl render-markdown example — Gemini implementation session rendered as markdown
session-id backend model start-time
ee0f6c4c-61c8-438a-9172-42ca9efc47fe
gemini
gemini-2.5-pro
2026-02-20T02:53:11.321Z

User

Implement the following plan. Return the complete modified files - show the FULL file content for each file, not just diffs or snippets.

@possibilities
possibilities / codexctl-example.md
Created March 11, 2026 16:03
codexctl render-markdown example — Codex design discussion rendered as markdown
session-id backend model cli-version cwd git-branch
019cd963-cb29-7cf2-becb-4777b249ee70
codex
gpt-5.4
0.113.0
/Users/mike/code/arthack
main

User

@possibilities
possibilities / 01-arthack-diverse-agent-progress.md
Created March 10, 2026 16:24
claudectl render-markdown example transcripts
session-id
13a8152e-9f5a-4387-ba70-35352b0a460f

User

/arthack:question

Can you explain the algorithm/process we use to sync claude sessions to chromadb? how often? Do we incrementally add conversations? What if a conversations updates? When I semantic search the db how fresh can I expect it to be?

Models Alongside QMD on RTX 3060 Ti (8GB)

With QMD using ~3GB, you'd have ~5GB free.

Audio Transcription

Model VRAM Quality Fits alongside QMD?
Whisper small ~2 GB Good for clear audio Yes, easily
Whisper medium ~5 GB Great, near-SOTA Tight but yes

RTX 3060 Ti for QMD Inference

For the QMD stack, it'll be great:

QMD models (~3GB VRAM total):

Model Size What it does Expected speed
embeddinggemma-300M Tiny Document embedding Near-instant, batch hundreds/sec
Qwen3-Reranker-0.6B Small Reranking results Very fast, sub-100ms per query
qmd-query-expansion-1.7B Medium Query expansion Fast, probably 80-100+ tok/s