A free ESG stock screener that publishes its losses and methodology
Hey HN, JSS(JumpstartSignal) is a free, ESG-filtered daily stock screener. I built it after some really badly-timed quantum computing stock buys, so I felt I needed to learn more about systematic, longer-horizon approaches and the underlying technicals instead of chasing themes. Three things about it that might be of interest:1. Methodology is fully documented at https://jumpstartsignal.com/how-it-works/ 5-stage pipeline, 54 signals tested individually plus 1,836 combinations evaluated, walk-forward validation across 25 hold periods. Nothing hand-tuned to a single backtest window.2. Many wins, misses, and losses are published as case studies e.g. https://jumpstartsignal.com/case-studies/nvda/ walks through the 32 times the system flagged NVDA starting at $5.44 in 2018. https://jumpstartsignal.com/case-studies/sedg/ shows a -49% loss, and https://jumpstartsignal.com/case-studies/tsla/ explains why the system never flagged Tesla (it passed Stages 1 and 2 on 207 days but only peaked at 20/100 in scoring vs the 70 needed for OPPORTUNITY tier). https://jumpstartsignal.com/results/ also shows the 10 best entries alongside the 10 worst.3. A genetic algorithm picked the signal weights, but constrained to maintain alpha across multiple market regimes (otherwise it overfits to a single bull market). The constraint dropped some "best in backtest" configurations that only worked 2018-2021.Topline: 2012-2025 backtest at SPOTLIGHT + OPPORTUNITY tier produced +163% alpha vs SPY (results page has the per-trade breakdown).Daily watchlist emailed free; reports + results + case studies are publicly browsable without signup.Happy to take questions about methodology, what the system gets wrong, or why specific tickers landed where they did.
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out of 100
Verdict
medium confidence
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A transparent stock screener with documented methodology and published losses, solving the trust problem in retail investing tools by showing exactly how it works and when it fails.
The pain
The gap
Build angle
Strengths
- Founder solved a real personal problem (bad stock picks) with systematic methodology, not theoretical speculation
- Published losses and case studies create credibility that competitors can't easily copy without admitting their own failures
- Genetic algorithm with multi-regime constraints shows technical rigor beyond typical retail tools
- Free distribution with email watchlist removes friction and builds user base for monetization
- Detailed methodology documentation lets users audit the approach and understand failure modes
- Walk-forward validation across 25 hold periods reduces overfitting risk compared to single-window backtests
Risks
- Backtested 163% alpha doesn't guarantee forward performance; 2012-2025 includes multiple bull markets where many strategies work
- No clear monetization model yet; free tools with email distribution don't generate revenue without conversion funnel
- Retail investor market is price-sensitive and attention-poor; users may not read methodology or case studies despite transparency
- Regulatory risk: publishing specific stock picks and performance claims could trigger SEC scrutiny around investment advice
- Competitive response: if the screener works, larger platforms (Bloomberg, Seeking Alpha, Finviz) can copy the transparency angle with more resources
- User retention depends on forward performance; one bad year of live results destroys the trust advantage
- ESG filtering narrows addressable market and may exclude high-performing stocks, limiting appeal to performance-focused investors
- No evidence users actually follow recommendations or that the system works in real-time with slippage, commissions, and execution delays
Fly Labs Method
Is the pain real, is there a gap, is it the right time, can one person build it.
Value Equation
Dream outcome and how likely it feels, against the time and effort it costs.
One-Person Business
Curiosity pull, identity fit, and a path from free value to paid for a solo creator.
Viral Frameworks
Hook strength, shareability, and how cheaply it can be tested.
Builder Lens
Evidence the problem exists, timing, defensibility, and a model that fits on a napkin.
Five lenses, one composite. How scoring works
The angle
No market research recorded for this idea yet.
Semble – Code search for agents that uses 98% fewer tokens than grep
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Postgres extension for BM25 relevance-ranked full-text search
Last summer we faced a conundrum at my company, Tiger Data, a Postgres cloud vendor whose main business is in timeseries data. We were trying to grow our business towards emerging AI-centric workloads and wanted to provide a state-of-the-art hybrid search stack in Postgres. We'd already built pgvectorscale in house with the goal of scaling semantic search beyond pgvector's main memory limitations. We just needed a scalable ranked keyword search solution too.The problem: core Postgres doesn't provide this; the leading Postgres BM25 extension, ParadeDB, is guarded behind AGPL; developing our own extension appeared daunting. We'd need a small team of sharp engineers and 6-12 months, I figured. And we'd probably still fall short of the performance of a mature system like Parade/Tantivy.Or would we? I'd be experimenting long enough with AI-boosted development at that point to realize that with the latest tools (Claude Code + Opus) and an experienced hand (I've been working in database systems internals for 25 years now), the old time estimates pretty much go out the window.I told our CTO I thought I could solo the project in one quarter. This raised some eyebrows.It did take a little more time than that (two quarters), and we got some real help from the community (amazing!) after open-sourcing the pre-release. But I'm thrilled/exhausted today to share that pg_textsearch v1.0 is freely available via open source (Postgres license), on Tiger Data cloud, and hopefully soon, a hyperscalar near you:https://github.com/timescale/pg_textsearchIn the blog post accompanying the release, I overview the architecture and present benchmark results using MS-MARCO. To my surprise, we were not only able to meet Parade/Tantivy's query performance, but exceed it substantially, measuring a 4.7x advantage on query throughput at scale:https://www.tigerdata.com/blog/pg-textsearch-bm25-fu
AI
Consus (YC F24) – LLM gateway for companies handling sensitive data
Hey Hacker News! I'm Eric, the founder of Consus. We route all AI requests to ITAR restricted and controlled unclassified information (CUI) compliant infrastructure. Consus itself satisfies ITAR restrictions, and we recently completed our FedRAMP equivalency audit against the 410 FedRAMP High controls. FedRAMP High is the U.S. government’s strictest security baseline for cloud services handling sensitive unclassified data. A breach of this data could cause severe or catastrophic harm. Achieving FedRAMP equivalency, or authorization, is required before processing CUI information.Demo: https://youtu.be/6MYxJe6P4oYAerospace and defense is experiencing rapid growth. Unfortunately, most companies are struggling to use AI because of necessary data protections & compliance risk. These companies can move even faster if they could use the AI tools that most other industries take for granted.I spent most of my career prior to Consus in aerospace & defense. I launched national security payloads at SpaceX, and was an early employee at Castelion. I’ve watched first hand how compliance red-tape makes it difficult for companies to adopt new technologies and trust vendors that touch their sensitive data. For example, I worked with a satellite manufacturer that doesn’t allow any AI tools, even for non-sensitive work.Even as AI has become extremely useful over the past 9-12 months, I was surprised by how many aerospace & defense companies refused to touch it. They could see how it could be helpful, but they were scared about model providers training on their data, violating an ITAR rule, or risk losing new business because of a failed cyber assessment. These are all rational fears.There were a lot of ways to solve some/all of these problems, but we focused on building a compliant AI inference layer that can "plug" into any AI tool or workflow. Just as OpenRouter integrates with most tools, Consus can connect to tools like ChatGPT or Clau
AI
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