[AINews] New AI Infra unicorns: Exa, Modal, TurboPuffer Exa raised $250 million at a $2.2 billion valuation in a Series C round, Modal raised $355 million at a $4.7 billion valuation in a Series C round, and Turbopuffer reached $100 million in annual recurring revenue and profitability, marking the emergence of three new AI infrastructure unicorns. The fundraises highlight continued investor appetite for AI infrastructure companies that provide search, cloud computing, and database services to the AI industry. AINews New AI Infra unicorns: Exa, Modal, TurboPuffer a quiet day lets us feature fundraises Take the 2026 AI Engineering Survey and get $2k in credits and AIE WF tickets Congrats to all our past guests who reached huge milestones this week: : $100M ARR and profitable Turbopuffer https://x.com/Sirupsen/status/2057470756070781400 our podcast https://www.latent.space/p/turbopuffer : $250M@$2.2B Series C Exa https://exa.ai/blog/announcing-series-c our podcast https://www.latent.space/p/exa : $355M@$4.7B Series C Modal https://x.com/bernhardsson/status/2057530320790995262?s=12 our podcast https://www.latent.space/p/modal We really need to be raising that Latent Space fund soon… but meanwhile.. help us out by taking the 2026 AI Engineering Survey https://notion.qualtrics.com/jfe/form/SV bP07tSVMXH7ePCS and get $2k in Notion and Vercel credits and AIE WF tickets https://ai.engineer/wf AI News for 5/20/2026-5/21/2026. We checked 12 subreddits, 544 Twitters and no further Discords. AINews’ website lets you search all past issues. As a reminder, AINews is now a section of Latent Space . You can opt in/out of email frequencies AI Twitter Recap Model, Benchmark, and Research Updates: RAEv2, Gated DeltaNet-2, Data Filtering, and Open Math RAEv2 and representation-first tokenization : Several researchers highlighted RAEv2 as a meaningful follow-on to Representation Autoencoders for unified vision understanding and generation. @1jaskiratsingh https://x.com/1jaskiratsingh/status/2057568174590304421 says the update yields 10x faster convergence , better reconstruction, and better generation, with tests extending to text-to-image and world models . A Chinese summary from @recatm https://x.com/recatm/status/2057456332861567359 usefully extracts the three main findings: summing the last K encoder layers instead of only the final layer improves both reconstruction and generation without added inference cost; RAE and REPA are complementary across semantics vs. spatial structure; and REPA can be reformulated as an internal self-guidance mechanism, avoiding extra weak-model guidance passes. @sainingxi e https://x.com/sainingxie/status/2057595509519311077 also points to new evaluation views beyond FID, arguing there is still underexplored headroom in representation-powered pixel decoders. Alternatives to standard attention and tokenizer assumptions : NVIDIA’sdecouples Gated DeltaNet-2 https://x.com/ahatamiz1/status/2057586630450610673 erase and write operations in linear attention with channel-wise gates, outperforming KDA and Mamba-3 at 1.3B parameters on language modeling and commonsense reasoning, with notable long-context retrieval gains on RULER ; @rasbt https://x.com/rasbt/status/2057599925878169761 called it one of the more interesting hybrid-attention directions. On tokenization, @NousResearch https://x.com/NousResearch/status/2057610978934546805 released a controlled study of why subword tokenization helps, simulating seven hypothesized benefits inside a 1.7B byte-level pipeline; only three of seven interventions moved validation loss at that scale. Separately, @tatsu hashimoto https://x.com/tatsu hashimoto/status/2057489411768803526 reported a surprising scaling result on DCLM : with enough compute, the best data filter may be no filter , with projections suggesting the crossover for internet-scale pools lands around 1e30 FLOPs ; downstream evals appear noisy but directionally consistent follow-up https://x.com/tatsu hashimoto/status/2057489440273322447 . Mechanistic interpretability and geometry : @GoodfireAI https://x.com/GoodfireAI/status/2057487848258101551 argues the dominant “models think in curved manifolds, SAEs use straight-line features” critique is only partly right. Their proposed fix is to cluster SAE features by joint firing patterns , recovering geometry through feature groups rather than isolated atoms thread continuation https://x.com/GoodfireAI/status/2057487927089954962 , post https://x.com/GoodfireAI/status/2057487939836502461 . This is a useful update to the current SAE discourse: not a rejection of sparse features, but a warning that interpretation should move from single features to structured ensembles. Math as an AI research domain : The biggest scientific discussion centered on OpenAI’s reported result on an Erdős unit-distance problem. @markchen90 https://x.com/markchen90/status/2057517045575774598 framed it as evidence that mathematics is currently the domain most amenable to AI-assisted research breakthroughs, while @wtgowers https://x.com/wtgowers/status/2057536069218742518 noted that if the reported low human interaction level holds, the result is genuinely interesting. The discourse was immediately shaped by skepticism and benchmark/gameability concerns, with @memecrashes https://x.com/memecrashes/status/2057478155246440929 joking that the result was “outdated not even 3 hours later by a human,” and @cloneofsimo https://x.com/cloneofsimo/status/2057486750004756524 pointing out the predictable “goalpost moving” around what counts as legitimate AI mathematics. The interesting technical meta-point is that math continues to function as a relatively legible frontier for AI co-research because outputs can be checked, debated, and extended. Agents, Harnesses, and Developer Tooling: Codex, Gemini, Devin, and Agent Infrastructure Harnesses are still a major source of capability gains : @lvwerra https://x.com/lvwerra/status/2057476832664953225 released physics-intern , a science-problem harness that boosts models like Gemini 3.1 Pro from 17.7 to 31.4 , surpassing GPT 5.5 Pro in that setup. The notable nuance is that GPT 5.5 Pro itself did not benefit from the harness, suggesting model-specific absorption of scaffolding tricks. In the same spirit, @KLieret https://x.com/KLieret/status/2057471442066030795 made mini-swe-agent runnable on ProgramBench , explicitly aiming to improve harness innovation around software engineering agents. Agent design patterns are maturing from “single agent first” to explicit subagent orchestration : @cwolferesearch https://x.com/cwolferesearch/status/2057486293882282293 gives a practical synthesis: start with single-agent systems , and only move to manager/sub-agent or decentralized multi-agent topologies when tool sprawl or prompt bloat becomes unmanageable. That advice lines up with more operational observations from users of subagents: @andrew locke https://x.com/andrew locke/status/2057537633555993058 describes Cognition’s sub-Devin workflow as a step change, compressing what previously looked like 2+ engineer-weeks into a couple of hours. Codex shipped a substantial product layer on top of the model : OpenAI’s “Codex Thursday” updates matter less as standalone features than as signs of where coding agents are going. @OpenAIDevs https://x.com/OpenAIDevs/status/2057530207976989179 launched Appshots , which capture both screenshot and text from Mac app windows for richer working context; they also added team plugin sharing link https://x.com/OpenAIDevs/status/2057530212339097994 and more detailed org analytics link https://x.com/OpenAIDevs/status/2057530213974814844 . The more important systems shift is remote computer use: @OpenAIDevs https://x.com/OpenAIDevs/status/2057536706778378692 says Codex can now securely use apps on your Mac from your phone even when the Mac is locked . This is a strong signal that the agent product surface is moving from chat IDEs to persistent cross-device operator workflows. Gemini’s agent/tool story is broadening quickly : @OfficialLoganK https://x.com/OfficialLoganK/status/2057460544643404125 highlighted that Gemini 3.5 Flash ranks 1 on APEX-Agents-AA , outperforming larger models. On the applied side, @ philschmid https://x.com/ philschmid/status/2057513254856151339 shows a GitHub issue triage agent built with a single Gemini API call and no orchestration framework, while @skalskip92 https://x.com/skalskip92/status/2057502215506473121 demonstrates Gemini 3.5 Flash replacing a custom vision pipeline for lane/car reasoning with one multimodal API call. Google also expanded action surfaces: Daily Brief announcement https://x.com/GeminiApp/status/2057500470147698936 and connected-app actions with OpenTable, Canva, and Instacart announcement https://x.com/GeminiApp/status/2057550225863246236 are essentially consumer-facing agent workflows. Developer infra is converging around retrieval, streaming, sandboxes, and security boundaries : Weaviate shipped a built-in MCP server inside the database so coding agents can ingest a repo and use hybrid BM25 + vector retrieval without extra processes announcement https://x.com/weaviate io/status/2057476556449010024 . LangChain introduced both a sandbox Auth Proxy for controlling agent-world boundaries announcement https://x.com/LangChain/status/2057508777759236401 and a new typed streaming protocol for rendering tools, subagents, media, and interrupts as first-class projections rather than token streams overview https://x.com/bromann/status/2057507753191518602 . vLLM’s Elastic Expert Parallelism is also notable systems work: @vllm project https://x.com/vllm project/status/2057602243860574463 describes live resizing of MoE DP/EP topology without full restarts, using direct GPU-to-GPU transfers over NVLink/RDMA —important not just for scaling but for future fault-tolerant serving. Infrastructure, Compute, and AI Business Signals: Modal, Turbopuffer, Hark, and the Compute Race The infra layer had one of its clearest “this is where the money is” days : @Sirupsen https://x.com/Sirupsen/status/2057470756070781400 said turbopuffer crossed $100M run-rate in March, just 19 months after $1M , while being profitable and raising < $1M . The company’s positioning is straightforward and timely: frontier teams know “the magic happens with AI when it draws in just the right context,” which turns a lot of product differentiation into a search/retrieval problem follow-up https://x.com/Sirupsen/status/2057470791516844188 . That aligns with broader sentiment from @swyx https://x.com/swyx/status/2057543654340710556 that “boring” AI infrastructure, not only glamorous frontier research, is where wealth creation is accruing. Modal raised big and continues to look like a core AI cloud winner : @bernhardsson https://x.com/bernhardsson/status/2057530320790995262 announced a $355M Series C at a $4.65B valuation . Investors and users emphasized the same thesis: rebuilding the cloud stack for AI workloads from the ground up, with strong performance and developer experience Redpoint https://x.com/Redpoint/status/2057532087570166134 , user endorsement https://x.com/mathemagic1an/status/2057534253790097788 . This sits alongside other signals that agent-native compute is emerging as its own category; @latentspacepod https://x.com/latentspacepod/status/2057565350187995260 summarized Daytona’s pitch around 60ms sandboxes , 50K startups in 75 seconds , and RL/evals workloads now representing roughly half of usage. Compute remains the strategic bottleneck, and the market appears tiered : @AymericRoucher https://x.com/AymericRoucher/status/2057492189626720729 sketched a useful compute taxonomy: US leaders OpenAI, Anthropic, Google, with Meta/xAI joining in the multi-gigawatt class; Chinese giants scaling from hundreds of MW toward multi-GW, increasingly on domestic stacks; and European contenders such as Mistral at around 90 MW today aiming for 1 GW by 2029 . The exact numbers are debatable, but the framing is consistent with @EpochAIResearch https://x.com/EpochAIResearch/status/2057499893854536185 , which notes that even if OpenAI kicked off the recent compute buildout, frontier labs still use well under all global compute capacity, leaving open the question of how much further the buildout can accelerate. Component economics also continue to shift toward memory: @EpochAIResearch https://x.com/EpochAIResearch/status/2057531410030997789 reports HBM grew from 52% to 63% of total AI chip component spending from Q1 2024 to Q4 2025. Capital is flowing to interface/hardware bets as well as infra : @adcock brett https://x.com/adcock brett/status/2057462134989263047 announced Hark raised $700M at a $6B valuation , aimed at GPU infrastructure, future model development, hardware, and multimodal/personal intelligence products. The details are sparse beyond hiring areas—foundation models, infra, speech, computer-use agents, hardware—but the size of the raise shows investor appetite for vertically integrated AI-device bets. Hark also reported a 200-hour uninterrupted autonomous run for F.03 announcement https://x.com/adcock brett/status/2057651077928145235 , though without enough technical detail yet to evaluate the underlying robotics stack. Multimodal, Video, Biology, and Robotics: Runway, Carbon, Earth Models, and Open Humanoids Video editing and generation are getting more compositional : Runway launched Aleph 2.0 and the new Edit Studio , letting users edit a single frame and propagate that edit through the rest of the video Runway https://x.com/runwayml/status/2057530497597600169 , product lead https://x.com/iamneubert/status/2057535909524824226 . This is a practical productization of the “reference-guided edit propagation” problem that multimodal builders care about. Separately, Alibaba researchers’ MIGA was flagged by @HuggingPapers https://x.com/HuggingPapers/status/2057506246899724355 as a train-free method for infinite-frame video generation with a two-stage alignment mechanism for temporal consistency. On the open-source avatar side, Meituan released LongCat-Video-Avatar 1.5 with Whisper-Large replacing Wav2Vec2, 8-step inference , long-video identity consistency, and broader stylized-domain generalization announcement https://x.com/Meituan LongCat/status/2057494106889486646 . Foundation models for biology and Earth observation continue to become more usable : Hugging Face Bio’s Carbon DNA model family got follow-on demos and infra validation. @LoubnaBenAllal1 https://x.com/LoubnaBenAllal1/status/2057488110263435640 highlighted applications in sequence design, variant effect prediction, and learned representations , while @Shekswess https://x.com/Shekswess/status/2057468970471448787 showed Carbon-500M, 3B, and 8B compiling and running on a single Trainium2 trn2.3xlarge with NxD Inference on day one. For geospatial modeling, @cgeorgiaw https://x.com/cgeorgiaw/status/2057481909802774664 reported OlmoEarth v1.1 is 3x cheaper/faster by changing the tokenization of multi-resolution Sentinel-2 inputs into 3x fewer tokens , exploiting the quadratic compute savings. Open robotics is getting more buildable : Hugging Face’s LeRobot Humanoid drew attention as a genuinely full-stack open release rather than a showcase demo. @robotsdigest https://x.com/robotsdigest/status/2057507896129380581 and @lukas m ziegler https://x.com/lukas m ziegler/status/2057515219946205399 both emphasize the same package: roughly $2.5k , 3D-printed , complete hardware/CAD, calibration/runtime, simulation, identification tools, and training pipelines. The key point is not just affordability; it’s repairability and iteration speed for real robot learning workflows. Top tweets by engagement OpenAI / Codex product expansion : Codex can securely use apps on your Mac from your phone, even when the Mac is locked https://x.com/OpenAIDevs/status/2057536706778378692 , plus Appshots https://x.com/OpenAIDevs/status/2057530207976989179 for richer app context. Infrastructure winners : turbopuffer at $100M run-rate, profitable, < $1M raised https://x.com/Sirupsen/status/2057470756070781400 ; Modal raises $355M Series C at $4.65B https://x.com/bernhardsson/status/2057530320790995262 ; Hark raises $700M at $6B https://x.com/adcock brett/status/2057462134989263047 . Research discussions with broad technical resonance : OpenAI’s Erdős-related math result discussion https://x.com/markchen90/status/2057517045575774598 ; RAEv2 release https://x.com/1jaskiratsingh/status/2057568174590304421 ; “no filter” scaling result for LM data curation https://x.com/tatsu hashimoto/status/2057489411768803526 . Agent capability trendlines : Gemini 3.5 Flash tops APEX-Agents-AA https://x.com/OfficialLoganK/status/2057460544643404125 ; Gemma 4 E4B driving an iOS simulator on-device via Argent https://x.com/googlegemma/status/2057570113390551452 ; Devin for Windows https://x.com/cognition/status/2057496130225668360 . AI Reddit Recap Keep reading with a 7-day free trial Subscribe to Latent.Space to keep reading this post and get 7 days of free access to the full post archives.