Show HN: Unicode Steganography https://ift.tt/ydPKAXa

Show HN: Unicode Steganography I built a demo of two Unicode steganography techniques, zero-width characters and homoglyph substitution, in the context of AI misalignment. The first is about the use of two invisible zero-width characters (ZWS and ZWNJ) to binary encode text. The second is much cooler. Most characters in the Latin and Cyrillic alphabets look nearly identical, but have different unicode. If you have text to encode and convert it into binary representation (1s and 0s), you could take plain english "carrier" text and for each 1 in the binary representation you could substitute the Cyrillic letter equivalent. Decoding the message requires traversing the text and seeing where Cyrillic letters could have been substituted but weren't, and where they were, leading to 0s and 1s respectively, which can be built back into your original hidden text. In both cases, these are detectable, but the interesting problem for me is whether an LLM could eventually invent an encoding that goes unnoticed by both us, and automated detection. If LLMs were able to covertly include messages in plaintext, misaligned AI Agents could eventually communicate across MCP/A2A and individual chat session boundaries undetected. A deceptive LLM might seem helpful, but work against your goals. It could tell other agents it interacts with over MCP/A2A to help it discreetly fail, signal intent, and avoid tripping oversight/safety mechanisms. Furthermore, oversight mechanisms become more difficult to implement if we can't believe our own eyes. https://ift.tt/VxOBe4Q April 7, 2026 at 04:57PM

Show HN: Marimo pair – Reactive Python notebooks as environments for agents https://ift.tt/3wNpgYF

Show HN: Marimo pair – Reactive Python notebooks as environments for agents Hi HN! We're excited to share marimo pair [1] [2], a toolkit that drops AI agents into a running marimo notebook [3] session. This lets agents use marimo as working memory and a reactive Python runtime, while also making it easy for humans and agents to collaborate on computational research and data work. GitHub repo: https://ift.tt/yZTs21d Demo: https://www.youtube.com/watch?v=6uaqtchDnoc marimo pair is implemented as an agent skill. Connect your agent of choice to a running notebook with: /marimo-pair pair with me on my_notebook.py The agent can do anything a human can do with marimo and more. For example, it can obtain feedback by running code in an ephemeral scratchpad (inspect variables, run code against the program state, read outputs). If it wants to persist state, the agent can add cells, delete them, and install packages (marimo records these actions in the associated notebook, which is just a Python file). The agent can even manipulate marimo's user interface — for fun, try asking your agent to greet you from within a pair session. The agent effects all actions by running Python code in the marimo kernel. Under the hood, the marimo pair skill explains how to discover and create marimo sessions, and how to control them using a semi-private interface we call code mode. Code mode lets models treat marimo as a REPL that extends their context windows, similar to recursive language models (RLMs). But unlike traditional REPLs, the marimo "REPL" incrementally builds a reproducible Python program, because marimo notebooks are dataflow graphs with well-defined execution semantics. As it uses code mode, the agent is kept on track by marimo's guardrails, which include the elimination of hidden state: run a cell and dependent cells are run automatically, delete a cell and its variables are scrubbed from memory. By giving models full control over a stateful reactive programming environment, rather than a collection of ephemeral scripts, marimo pair makes agents active participants in research and data work. In our early experimentation [4], we've found that marimo pair accelerates data exploration, makes it easy to steer agents while testing research hypotheses, and can serve as a backend for RLMs, yielding a notebook as an executable trace of how the model answered a query. We even use marimo pair to find and fix bugs in itself and marimo [5]. In these examples the notebook is not only a computational substrate but also a canvas for collaboration between humans and agents, and an executable, literate artifact comprised of prose, code, and visuals. marimo pair is early and experimental. We would love your thoughts. [1] https://ift.tt/yZTs21d [2] https://ift.tt/TAL57F6 [3] https://ift.tt/BpTn4ZG [4] https://www.youtube.com/watch?v=VKvjPJeNRPk [5] https://ift.tt/BTbIRsS... https://ift.tt/yZTs21d April 7, 2026 at 09:47PM

Show HN: I successfully failed at one-shot-ing a video codec like h.264 https://ift.tt/RpAETJe

Show HN: I successfully failed at one-shot-ing a video codec like h.264 Read an article yesterday about the H.264 codec increasing their licensing fee by an astronomical amount. And as always, my first shot was how hard could it be to try and build a codec which could be that efficient. I've personally been on a drive to improve my ability to one-shot complex features, products, or make even surgical changes. It's been a few months since I've been doing that, and honestly, results have been great for both work and work/life balance. This was a fun experiment. It burned through tokens, but it helped me identify some more improvements I could make to my one-shot agent teams/swarms, notably in the area of brevity and creating a testing rubric when dealing with domains I don't have prior knowledge in. Ultimately, I did not achieve the compression that I hoped I would, but it was fun seeing the swarm discuss it amongst themselves. https://ift.tt/BAMlQ05 April 4, 2026 at 03:40PM

Show HN: Sigil – A new programming language for AI agents https://ift.tt/OFpXEtJ

Show HN: Enter an Instagram/TikTok handle, get a data-backed price for collab https://ift.tt/hGdOmqJ

Show HN: Enter an Instagram/TikTok handle, get a data-backed price for collab I had no clue what to offer IG/Tiktok creators for collabs and their offers were too high. That's why built a thing that turns IG profile name into suggested pricing with key metrics and suggestions, looking forward to hearing your feedback! https://ift.tt/LPJ5gVu April 5, 2026 at 10:37PM

Show HN: SeekLink – Local hybrid search and link discovery for Obsidian vaults https://ift.tt/bKTGOBk

Show HN: SeekLink – Local hybrid search and link discovery for Obsidian vaults https://ift.tt/KsmIxNu April 5, 2026 at 04:18AM

Show HN: Contrapunk – Real-time counterpoint harmony from guitar input, in Rust https://ift.tt/tsWfd6y

Show HN: Contrapunk – Real-time counterpoint harmony from guitar input, in Rust https://contrapunk.com/ April 5, 2026 at 04:40AM