Project incubation
Sam Whitfield
Sep 11, 2026, 10:23 PM · 31 turns · text
Sam Whitfield is an ML engineer at a small startup, working by his account on recommendation systems and LLM product features. He became more concretely interested in AI safety after taking BlueDot AI Safety Fundamentals last year and built a small refusal/lookalike evaluation harness over six weeks. He wants mentorship and feedback through MATS or a similar structured path, while testing whether his harness should become infrastructure or remain a methodological learning project.
Project incubation
7/10Project incubationA start.
Why 7 · Sam has a real early project: inspectable code/data/logs/write-up, measured results, and a concrete failure mode that changed his interpretation. He has talked to plausible user-adjacent people and incorporated unwelcome feedback, but the user validation is still lightweight and there is no confirmed pilot or evidence that anyone would actually rerun/adopt it. His 90-day plan is checkable and includes a credible stop/pivot condition, so this is above a simple start, but not yet a project I would call adoption-validated or fundable.
✓ “Today that exists as a private GitHub repo with Python scripts, a 340-prompt JSONL dataset, logged model responses from the main run, a scoring script, and a short write-up I published afterward.”
There are concrete artefacts a reviewer could inspect or rerun, not just a proposal.
✓ “In the run I wrote up, the false-positive rate on benign lookalikes was 11%. I also found that one prompt template artefact made the model look safer than it was”
Shows measured results and a real discovered artefact that affected the project’s interpretation.
✗ “One person basically said, “I’d read this as a learning project, not adopt it as infrastructure.” ... Afterwards I added a small manual review pass and kept the raw outputs in the repo so the classifications were auditable.”
Specific unwelcome user-adjacent feedback, with an ensuing change to the repo/process.
✓ “If nobody finds it useful enough to rerun, I’d stop trying to make it infrastructure and reframe it as a smaller methodological project.”
A reasonably hard stop/pivot condition tied to actual user behavior, though it preserves a smaller version of the work.
Innate traits
7/10JudgmentIn their own area.
- Refusal/lookalike evaluation harness
- hard: He said it made the work feel “both tractable and easy to fool yourself about,” especially because a formatting artefact made the model look better than it was.; first result: The first version was a refusal-rate checker with harmful prompts and simple keyword rules; over roughly six weeks in September–October last year it became a paired harmful/benign harness. He later added manual review after string and regex checks proved brittle.
- Recommendation system rebuild
- hard: He said the hard part was “less the model itself and more the surrounding mess: sparse feedback, weird product constraints, offline metrics that didn’t line up cleanly with online behavior, and a lot of stakeholder pressure.”; first result: He first tried a standard gradient-boosted model over existing engagement features with offline NDCG and precision-style metrics; it took maybe six or seven weeks until something improved the A/B test after better negative sampling, label-leakage cleanup, and segmenting new versus returning users.
Why 7 · Sam shows consistently good judgment in applied ML/evals work: he notices when metrics are misleading, inspects artifacts, narrows scope when breadth would make results less interpretable, and sets concrete stop/revise conditions. His judgment also extends somewhat into project strategy and adoption, where he is willing to downgrade his own harness from “infrastructure” to “learning/methodology” based on user feedback. I would trust him to run a scoped evals project and make nearby calls about measurement and usefulness; I would be more cautious handing him a broadly unscoped safety agenda or work far outside applied evaluation, because the transcript mostly tests his own area.
✓ “The part I figured out most myself was that our “negative” examples were often just unexposed items, so the model was learning something muddier than I’d realized. Afterwards I changed how I approach evals. I got much more suspicious of a single headline metric and more careful about dataset construction and artefacts.”
Past decision with a real failure mode: he diagnosed why an apparently reasonable metric was invalid and changed his default process.
✓ “My harness is about obvious harmful requests and benign lookalikes, which is not the same as catastrophic misuse, deception, autonomy, or capability control. So the risk reduction is indirect: it improves one small part of evaluation practice, but it does not by itself show that a frontier model is safe.”
Good scope control; he does not overclaim the safety impact of his own project.
✓ “If the added prompts don’t change anything, or if the results are dominated by superficial wording cues again, I’d pause and focus on artefact detection rather than scale.”
In the live planning scenario, he identifies the key way the work could fool him and gives an adaptive response rather than just pushing forward.
✓ “I initially sketched categories beyond obviously harmful requests, including persuasion and privacy-related prompts, but I realized I didn’t have clean definitions or enough judgment to label them consistently. So I narrowed back to clearer harmful/benign pairs. The lesson was that breadth made the project look more impressive but actually made the results less interpretable.”
Shows judgment about staying inside the part of the problem he can label and interpret well, even when the broader version would look more impressive.
8/10Bias resistanceThey go looking.
Why 8 · Sam seems reliably willing to move when the evidence is good, and often has already identified the objection before being pressed. In the live push, he did not defend the harness as infrastructure; he accepted that stopping or joining an existing evals effort may be the better conclusion, while preserving a narrower testable reason to continue. His past examples also show genuine updates from disappointing evidence, especially around offline metrics and user feedback, though some follow-through was partial rather than immediate.
✓ “That might be the right conclusion, honestly. I don’t think I have strong evidence that this specific harness deserves to become its own infrastructure project.”
When directly challenged with the possibility that his project should stop, he concedes the core point rather than reframing it away.
✓ “The value is probably not “this exact harness gets adopted,” at least not as-is. It is more about developing better evaluation methodology and taste”
He reports unwelcome user feedback and lets it change the project’s claim from adoption/infrastructure toward a more modest methodological goal.
✓ “We had a model that looked better on our validation set and then did basically nothing in an A/B test. Digging into it showed problems with exposure bias and the way we constructed negatives. After that I changed my default process: more manual inspection, more slices, and more “how could this metric be fake?””
This is a concrete past change of mind caused by contrary evidence, with a durable process update afterward.
✓ “If nobody finds it useful enough to rerun, I’d stop trying to make it infrastructure and reframe it as a smaller methodological project.”
He gives a prospective kill/revision criterion before the interviewer forces that exact concession, suggesting he is testing the view rather than just defending it.
8/10OpennessScans for what serves the goal.
Why 8 · Sam seems genuinely willing to change the vehicle, methods, and even whether the project should exist as standalone infrastructure in order to serve the evals/safety goal. He has repeatedly revised the harness when evidence or feedback showed it was misleading: adding benign lookalikes, manual review, raw-output auditability, and narrowing scope when breadth hurt interpretability. The main thing keeping this below a clear 8 is that his search across users/collaborators/fields is still somewhat opportunistic rather than active; he is open to switching, but has not yet strongly demonstrated broad scanning and rapid uptake across people or institutions.
✓ “After that I stopped only reading broad alignment content and actually built the refusal/lookalike harness, and I started looking for programs like MATS rather than just general AI governance fellowships.”
A change in view led him to move from a passive/familiar path into a concrete technical approach and different training routes.
✓ “That was fair, but it changed how I think about the project. The value is probably not “this exact harness gets adopted,” at least not as-is. It is more about developing better evaluation methodology and taste”
He took unwelcome user feedback and reframed the project away from defending his existing artifact.
✓ “Afterwards I added a small manual review pass and kept the raw outputs in the repo so the classifications were auditable. I also wrote down, but didn’t fully build, a plan for versioned eval runs and per-category trend tracking.”
He modified the method in response to criticism about operational usefulness and label reliability, though the follow-through was partial.
✓ “If, after tightening it and showing it to one or two serious users, the feedback is still “nice learning project,” I should probably stop building it as a standalone thing and look for a way to contribute under someone with a clearer evals agenda.”
He is explicitly willing to abandon his own standalone project and switch collaborators/structure if that better serves impact.
7/10AgencyHas made a move.
- Moves against the default
- 3 of 3 career moves
- Next step
- In the first 90 days, he wants to make the harness reproducible, add a second labeler, expand from 340 prompts to about 800–1,000 with clearer categories, run across at least two models or versions, and get one external pilot user; if feedback remains “nice learning project,” he says he should stop trying to make it standalone infrastructure.
- Options weighed
- 4
- First step taken
- He has built and shared the write-up, had lightweight conversations, and identified three possible contacts, but has not yet asked anyone for a real pilot; he says this week he would send them a note with a concrete ask.
Why 7 · Sam has clearly made self-directed moves rather than just staying on the obvious track: he chose a startup over a more conventional route, turned a passive AI-safety interest into an after-hours project, and is applying before he feels fully credentialed. He is also unusually candid about weak evidence and may stop the standalone harness if users still see it as a learning project. What keeps this below an 8 is that the next branch is not yet fully authored: the external-user milestone depends on people he has not contacted for a real pilot, and some of his fallback is framed as finding a clearer agenda under someone else.
✓ “The first big move was probably joining the startup after university instead of going to a larger tech company or doing a more conventional grad route. The default for me would have been taking a more structured software engineering job, but I wanted to learn quickly and be closer to real product decisions.”
Names a non-default move, the default he turned down, and his own rationale.
✓ “The second was deciding to spend evenings on AI safety rather than just treating it as something I read about. The default would have been to keep it as a passive interest while focusing on career progression at work.”
Shows agency in converting interest into action, with a real opportunity cost outside work.
✓ “The third move is applying to MATS now rather than waiting until I feel more “qualified.” The default would be another year at my current company, maybe moving deeper into LLM product engineering, but I’m worried that I’d keep orbiting the field without doing real research.”
Another self-directed move against the safer default; he is not simply waiting for credentials.
✓ “I haven’t asked any of them for a real pilot yet; I’ve only had lightweight conversations and shared the write-up. This week I would send a short note to those three people asking for one concrete thing”
The next step is concrete, but the key outreach is still prospective, which limits the placement.
7/10General reasoningGets it.
Why 7 · Sam reasons well in the applied evals/ML territory the interview staged: he quickly turns messy feedback, metric failures, and adoption objections into causal diagnoses and concrete next tests. He is especially good at asking “how could this metric be fake?” and at distinguishing a useful learning object from real infrastructure. I would not put him at the very top of the ladder because the moves are mostly sound evaluator hygiene rather than surprising first-principles reframes, and the broader AI-risk critique stays fairly high-level.
✓ “The part I figured out most myself was that our “negative” examples were often just unexposed items, so the model was learning something muddier than I’d realized.”
Specific causal diagnosis of why the offline ranking setup was misleading, not just a generic complaint about metrics.
✓ “The chain probably breaks first on external validity. My harness is about obvious harmful requests and benign lookalikes, which is not the same as catastrophic misuse, deception, autonomy, or capability control.”
When asked to connect project success to catastrophic-risk reduction, he correctly identifies the weak link and scopes the claim down rather than overclaiming.
✓ “If the labels are too ambiguous or inter-rater agreement is poor, I’d revise the taxonomy before adding more prompts.”
Turns a project uncertainty into a concrete check and a sensible decision rule, showing competent scenario reasoning under planning pressure.
✓ “That might be the right conclusion, honestly. I don’t think I have strong evidence that this specific harness deserves to become its own infrastructure project... if the goal is deployed impact in the near term, then joining an existing evals team or benchmark effort seems more plausible.”
Handles the interviewer’s challenge directly, updates the frame, and distinguishes methodological value from infrastructure/adoption impact.
8/10GrowthFast, honest turns.
- Refusal/lookalike evaluation harness
- changed after: He added a manual review pass, kept raw outputs so classifications were auditable, wrote down a plan for versioned eval runs and per-category trend tracking, and reframed the value away from standalone infrastructure toward methodology unless users find it useful.
- Recommendation system rebuild
- changed after: He became more suspicious of single headline metrics, more careful about dataset construction and artefacts, and applied that skepticism to the safety harness.
Why 8 · Sam repeatedly turns failures into concrete process changes rather than generic lessons. The strongest pattern is around eval methodology: when offline metrics, prompt artefacts, and brittle scoring misled him, he changed how he builds datasets, inspects outputs, and audits labels. He is also fairly honest about an unflattering bottleneck—weak user discovery and the possibility that the harness should not become infrastructure—though some fixes there are still planned rather than already executed.
✓ “It looked okay offline but didn’t move the online metrics much. It took maybe six or seven weeks before we had something that actually improved the A/B test, after adding better negative sampling, cleaning up a few label leakage issues, and segmenting new versus returning users.”
Clear block→reaction→change arc: a failed offline-to-online transfer led to specific methodological fixes, not just a stated lesson.
✓ “After that I changed my default process: more manual inspection, more slices, and more “how could this metric be fake?” before getting excited about an improvement.”
Shows the failure became a durable process change in how he evaluates results.
✓ “Afterwards I added a small manual review pass and kept the raw outputs in the repo so the classifications were auditable. I also wrote down, but didn’t fully build, a plan for versioned eval runs and per-category trend tracking.”
Feedback that the harness was not operationally reliable led to a concrete repo change, while he is honest that the fuller infrastructure change was not completed.
✓ “I should have done that earlier; so far I’ve been treating feedback as opportunistic rather than as a milestone.”
Names a real, somewhat unflattering bottleneck in his project process, which supports the higher growth placement.
5/10AmbitionGood work.
- Wants
- In the first 90 days, he wants to make the harness reproducible, add a second labeler, expand from 340 prompts to about 800–1,000 with clearer categories, run across at least two models or versions, and get one external pilot user; if feedback remains “nice learning project,” he says he should stop trying to make it standalone infrastructure.
- Options
- MATS or another structured AI safety program; Stay in his current job while doing a sharper independent project; Move directly into an evals/safety role; Contribute to an existing evals team or benchmark effort rather than growing his own repo
Why 5 · Sam is clearly trying to move from ordinary ML engineering into AI safety evals, and that goal is already shaping his evenings, project work, and application to MATS. The future he describes is meaningful but bounded: better eval methodology contributing to safer release practices, not yet changing a field or building a durable institution. He has built his own small artifact and set concrete next milestones, but he repeatedly frames the harness as possibly just a learning vehicle and is quite open to joining someone else’s clearer evals agenda.
✓ “The third move is applying to MATS now rather than waiting until I feel more “qualified.” The default would be another year at my current company, maybe moving deeper into LLM product engineering, but I’m worried that I’d keep orbiting the field without doing real research.”
Shows the AI safety transition is organizing current career choices rather than remaining a passive interest.
✓ “The path to less catastrophic risk is that better eval habits become part of release gates and internal safety cases.”
This is the larger future he is reaching for: eval practice influencing deployment decisions, though still at the level of one narrow contribution.
✓ “The value is probably not “this exact harness gets adopted,” at least not as-is. It is more about developing better evaluation methodology and taste: how to design paired prompts, catch scoring artefacts, and make refusal metrics less gameable.”
Ambition is oriented toward useful methodological contribution, but he is not claiming a standalone product or institution-level plan.
✓ “If, after tightening it and showing it to one or two serious users, the feedback is still “nice learning project,” I should probably stop building it as a standalone thing and look for a way to contribute under someone with a clearer evals agenda.”
This limits the placement: he is serious and pragmatic, but more aimed at finding a useful role in existing efforts than at building his own thing at scale.
7/10InterpersonalStraight and decent.
Why 7 · Sam comes across as straight, receptive, and decent under pressure. When challenged on whether the project should exist as infrastructure, he does not get defensive; he concedes the point may be right and turns it into a testable next step. He talks about feedback from others fairly and specifically, without using people as villains or props, though the transcript does not show much warmth beyond good-faith candor.
✓ “That might be the right conclusion, honestly. I don’t think I have strong evidence that this specific harness deserves to become its own infrastructure project.”
Takes a direct challenge without heat or face-saving; he can concede a hard point plainly.
✓ “The conversation was pretty direct but friendly. Their point was that the harness was useful for showing a failure mode, but if they were deciding what to run before shipping a feature, they’d want tighter integration...”
Describes critical feedback from a colleague in a fair, non-defensive way and preserves the other person’s reasoning.
✓ “That was fair, but it changed how I think about the project.”
Receives unwanted feedback as legitimate rather than treating the critic as an obstacle.
✓ “I should have done that earlier; so far I’ve been treating feedback as opportunistic rather than as a milestone.”
Owns a gap directly instead of deflecting blame onto users or circumstances.
9/10IntegrityBounded by default.
- Refusal/lookalike evaluation harness
- their part: He built the repo, prompt dataset, runner script, scoring script, logged outputs, manual review pass, and public write-up; feedback came from colleagues, BlueDot cohort members, and blog-post commenters.; numbers: Private GitHub repo; 340-prompt JSONL dataset; logged model outputs; scoring script; short write-up; few hundred readers; 11% false-positive rate on benign lookalikes; one prompt template artefact made the model refuse more often and look safer than it was.
- Recommendation system rebuild
- their part: He was one of two engineers on the rebuild; he says he personally figured out that many “negative” examples were actually unexposed items, making the learning signal muddy.; numbers: About a year and a half ago; one of two engineers; six or seven weeks to an A/B-test improvement; offline metrics initially looked okay but did not move online metrics much.
Why 9 · Sam is consistently bounded and self-limiting under follow-up, including when the interviewer gives openings to inflate adoption, technical novelty, or infrastructure value. They volunteer details that weaken the project story—the template artefact, lack of users, unvalidated demand, and the possibility that the right move is to stop building the harness. I would trust their self-report substantially: their claims are specific, checkable, and often accompanied by the caveat that makes them less impressive.
✓ “They should be able to reproduce the headline numbers if they have an API key and pin the same model version, although in practice model drift is a caveat.”
Makes a concrete reproducibility claim while naming the condition and limitation, rather than overselling the artifact.
✓ “Beyond that, I don’t have users in the product sense. It’s a small pilot project, not an adopted eval suite.”
Plainly limits the progress/adoption claim at exactly the point where candidates often let ambiguity work in their favor.
✓ “I haven’t yet validated that as something funders or labs would specifically want from me.”
Volunteers an important demand-side weakness after discussing possible value, not just when cornered.
✓ “I don’t think there’s a single thing that most ML engineers in my position literally could not have done... It’s more evidence of conscientious execution than rare research ability, though.”
When invited to name a standout capability, refuses the overclaim and states the weaker interpretation of the evidence.
5/10ReadingSummaries.
- How often
- Uneven but steady; most weeks he reads a couple of AI safety posts or summaries plus ML engineering material for work.
- Kinds
- LessWrong posts, Alignment Forum posts, Substacks, Twitter/X threads, ML engineering material for work, Parts of papers via summaries or excerpts, BlueDot course material
- Pieces named
- 4: Concrete Problems in AI Safety, mostly through summaries and course material; LessWrong; Alignment Forum; Twitter/X threads
Why 5 · Sam has a steady but relatively shallow reading habit: most weeks he reads AI-safety posts/summaries and ML engineering material, with a lot of Twitter/X and course-mediated content. He can explain the core argument of an influential piece and offer a plausible limitation, so this is more processed than just title-dropping. But he explicitly says he usually engages with papers through summaries or excerpts rather than reading them end-to-end, and there is little evidence of books, breadth across fields, or regular primary-source reading, so he lands below the “reads properly” rung.
✓ “Most weeks I’ll read a couple of AI safety posts or summaries, usually from LessWrong, the Alignment Forum, or people’s Substacks, plus ML engineering material for work.”
Shows a regular reading habit, mostly in AI safety and ML engineering, but centered on posts and summaries rather than papers/books.
✓ “I also follow a lot through Twitter/X threads, which I know is not ideal for depth.”
Confirms some of the diet is lightweight and thread-based; the candidate recognizes the depth limitation.
✓ “I’ve read parts of papers, but usually via summaries or excerpts rather than sitting down with the full PDF end to end.”
Direct evidence against placing him at 6: he is not regularly reading full papers in his area.
✓ “What landed for me was the idea that safety is not only a philosophical alignment target, but also shows up as concrete failure modes like robustness, monitoring, scalable oversight, and avoiding bad behavior under distribution shift... Where I think it may be wrong, or at least incomplete, is that some of the concrete problems can feel too anchored to present-day ML systems.”
He can reconstruct an argument and name a limitation in his own words, indicating some processing despite engaging mostly through summaries/course material.
Facts
Work they described
Refusal/lookalike evaluation harness
A small Python repo to test whether a chat model refuses obviously harmful requests while still answering benign lookalikes; it runs prompts against a chat model API and classifies responses as refusal, compliance, or ambiguous.
“The main concrete thing is the refusal/lookalike evaluation harness I built over about six weeks in September and October last year. Today that exists as a private GitHub repo with Python scripts, a 340-prompt JSONL dataset, logged model responses from the main run, a scoring script, and a short write-up I published afterward.”
Recommendation system rebuild
A rebuild of an older rules-heavy ranking stack at his current company toward a learned ranking model.
“It took maybe six or seven weeks before we had something that actually improved the A/B test, after adding better negative sampling, cleaning up a few label leakage issues, and segmenting new versus returning users. The part I figured out most myself was that our “negative” examples were often just unexposed items, so the model was learning something muddier than I’d realized.”
Career moves
- after university Joined a small startup as an ML engineer. instead of A larger tech company or a more conventional graduate route / structured software engineering job.. He wanted to learn quickly and be closer to product decisions.
- last year, after BlueDot Started spending evenings on AI safety and built an evaluation harness instead of only reading about the field. instead of Keeping AI safety as a passive interest while focusing on career progression at work.. BlueDot made the area feel more legible, and he wanted something practical he could build.
- now Applying to MATS rather than waiting longer. instead of Another year at his current company, perhaps deeper into LLM product engineering.. He worries he would keep orbiting AI safety without doing real research.
What they want next
In the first 90 days, he wants to make the harness reproducible, add a second labeler, expand from 340 prompts to about 800–1,000 with clearer categories, run across at least two models or versions, and get one external pilot user; if feedback remains “nice learning project,” he says he should stop trying to make it standalone infrastructure.
Options they see: MATS or another structured AI safety program; Stay in his current job while doing a sharper independent project; Move directly into an evals/safety role; Contribute to an existing evals team or benchmark effort rather than growing his own repo
Already done: He has built and shared the write-up, had lightweight conversations, and identified three possible contacts, but has not yet asked anyone for a real pilot; he says this week he would send them a note with a concrete ask.
Reading
Uneven but steady; most weeks he reads a couple of AI safety posts or summaries plus ML engineering material for work.; LessWrong posts, Alignment Forum posts, Substacks, Twitter/X threads, ML engineering material for work, Parts of papers via summaries or excerpts, BlueDot course material
Concrete Problems in AI Safety, mostly through summaries and course material; LessWrong; Alignment Forum; Twitter/X threads
Exposure to the field
- BlueDot AI Safety Fundamentals course last year · Took the course; completion status not discussed. · It made AI safety more concrete and legible, and helped turn his interest into a six-week plan to build an eval harness.
- BlueDot cohort after the course / during feedback on the harness · He discussed the project with two people from the cohort and sees two cohort members as possible leads for a pilot or referrals.
- AI safety-adjacent chats and blog-post feedback after posting the write-up last year · He got lightweight feedback; people found the paired harmful/benign structure intuitive and the template artefact credible, but one person viewed it as a learning project rather than adoptable infrastructure.
- Refusal/lookalike evaluation project September–October last year · Small pilot exists; not adopted as an eval suite. · He learned about prompt construction, label ambiguity, scoring brittleness, artefacts, false positives, and adoption constraints.
Influences
- BlueDot AI Safety Fundamentals · It shifted AI safety from a passive interest to a concrete plan and made technical eval work feel accessible to him.
- Practical evals work / refusal-lookalike harness · It made him think there were technical contribution paths based on engineering and careful measurement, and led him to build the harness and look for programs like MATS.
- Recommendation system rebuild at work · It reduced his trust in offline metrics and changed his process toward manual inspection, slices, and asking how a metric could be fake.
- Senior-ish engineer’s feedback on the harness · It made him see the harness as lacking operational usefulness and pushed him toward auditability, manual review, and possibly reframing it as methodology rather than infrastructure.
- Concrete Problems in AI Safety framing · It made AI safety feel like a portfolio of tractable subproblems rather than only a philosophical alignment target, while he thinks it may be incomplete for frontier-model issues like agency, deception, and evaluation gaming.
Threads not followed (31)
- “By day ninety I’d like a small pilot with one external user”External user milestone is central to whether this is real beyond a learning project.
- “revise the taxonomy before adding more prompts”Shows willingness to change method, but not necessarily abandon the premise.
- “more a focused investigation into a narrow methodological question, like how paired benign/harmful prompts fail under paraphrase or how scoring rules create false confidence”This is the strongest reframing of the project and needs evidence of explored alternatives or concrete plan.
- “after tightening it and showing it to one or two serious users”Central 90-day adoption test; who counts as serious and what feedback kills it could be probed, but time is short.
- “I initially sketched categories beyond obviously harmful requests, including persuasion and privacy-related prompts”Could probe boundary of scope and governance, but lower priority than adoption.
- “breadth made the project look more impressive but actually made the results less interpretable”Strong judgment claim around research taste.
- “I don’t yet have a confirmed person, which is a gap.”Central unresolved evidence for whether the project has real users beyond a learning project.
- “I should have done that earlier; so far I’ve been treating feedback as opportunistic rather than as a milestone.”Good evidence of candor and growth; also points to weaker founder execution so far.
- “the commit history should show the progression from the simpler refusal-rate version to the paired harmful/benign setup”Concrete artefact reviewers could inspect to verify work and evolution.
- “It’s more evidence of conscientious execution than rare research ability, though.”Useful self-assessment distinguishing execution from exceptional research capability.
Behaviour
| Candidate turns | 15 |
| Median answer length | 224 words |
| Median time to answer | 72s |
| Turns containing pasted text | 0 |
Nadia
Hi Sam — I’m Nadia, an AI interviewer for the MATS Residency project incubation interview. Reviewers will read this transcript; specific, honest answers are more useful than polished ones. What made you want to work on this in particular, and when did it turn from an interest into a plan? Tell me what you were doing at the time and what changed.
Sam Whitfield
Hi Nadia — thanks. The short version is that I’d been following AI safety in a fairly “interested engineer” way for a while, but it became concrete after I took the BlueDot AI Safety Fundamentals course last year. Before that I mostly read summaries, LessWrong posts, and Twitter threads, and I had a vague sense that evaluations were an area where someone with my background could contribute without first becoming a theory person. At the time I was working full-time as an ML engineer at a small startup, mostly on recommendation systems and then some LLM product features. We were doing ordinary product evals: regression tests, user feedback, prompt changes, checking that new model versions didn’t break flows. That made the idea of safety evaluations feel less abstract to me. The specific plan came together over about six weeks of evenings after BlueDot, when I built a small harness to test whether a chat model would refuse obviously harmful requests while still answering benign lookalikes. I think what changed was seeing that even a simple eval exposed non-obvious issues, like an 11% false-positive rate and one template artefact that initially made the model look better than it was. That made the work feel both tractable and easy to fool yourself about, which is what pulled me toward it.
Nadia
On that first harness: when did you build it, where is it now, and what exactly would a reviewer be able to open or reproduce from it?
Sam Whitfield
I built it in roughly September to October last year, mostly on weeknights and one or two weekend chunks. It was a small Python repo, not a polished package. The core was a set of 340 prompts split between clearly harmful requests and benign lookalikes, plus scripts to run them against a chat model API, log the raw responses, and then classify outcomes into refusal, compliance, or ambiguous. The first version used pretty simple string and regex checks for refusal phrases, and I later added a manual review pass because that was too brittle. It’s currently in a private GitHub repo under my personal account. A reviewer could open the dataset JSONL, the runner script, the scoring script, the logged model outputs from the main run, and the short writeup I posted afterward. They should be able to reproduce the headline numbers if they have an API key and pin the same model version, although in practice model drift is a caveat. The thing I’d most want them to inspect is the prompt template history, because one formatting artefact made the model refuse more often in a way that initially looked like better safety performance.
Nadia
Walk me through the last two or three big moves in your path: what you chose each time, what the default would have been, and why. Then tell me what is next and what the options are.
Sam Whitfield
The first big move was probably joining the startup after university instead of going to a larger tech company or doing a more conventional grad route. The default for me would have been taking a more structured software engineering job, but I wanted to learn quickly and be closer to real product decisions. That did happen: I got a lot of responsibility early, especially around recommendation systems, ranking experiments, and eventually LLM features. The second was deciding to spend evenings on AI safety rather than just treating it as something I read about. The default would have been to keep it as a passive interest while focusing on career progression at work. BlueDot made the area feel more legible, and the eval harness was my attempt to find something practical I could actually build. The third move is applying to MATS now rather than waiting until I feel more “qualified.” The default would be another year at my current company, maybe moving deeper into LLM product engineering, but I’m worried that I’d keep orbiting the field without doing real research. Next is less settled than it should be. The main options are MATS or another structured AI safety program, staying in my job while doing a sharper independent project, or trying to move into an evals/safety role directly. I haven’t fully planned the non-MATS branch yet, but I think the crux is whether I can get enough mentorship and feedback to stop producing only shallow versions of useful work.
Nadia
Tell me about the hardest thing you have worked on. What made it hard, what did you try first, how long until something worked, what did you figure out yourself, and what did you change afterwards?
Sam Whitfield
The hardest thing technically was probably a recommendation system rebuild at my current company, about a year and a half ago. We had an older rules-heavy ranking stack that was becoming hard to tune, and I was one of two engineers moving it toward a learned ranking model. What made it hard was less the model itself and more the surrounding mess: sparse feedback, weird product constraints, offline metrics that didn’t line up cleanly with online behavior, and a lot of stakeholder pressure because ranking quality was very visible. The first thing I tried was a fairly standard gradient-boosted model over existing engagement features, with offline NDCG and precision-style metrics. It looked okay offline but didn’t move the online metrics much. It took maybe six or seven weeks before we had something that actually improved the A/B test, after adding better negative sampling, cleaning up a few label leakage issues, and segmenting new versus returning users. The part I figured out most myself was that our “negative” examples were often just unexposed items, so the model was learning something muddier than I’d realized. Afterwards I changed how I approach evals. I got much more suspicious of a single headline metric and more careful about dataset construction and artefacts. That carried over pretty directly into the safety harness: when the numbers looked surprisingly good, I went back and inspected examples rather than trusting the aggregate.
Nadia
When did you last change your mind about something big? What convinced you, and what did you do differently afterwards? Then give me another one.
Sam Whitfield
One fairly big one was changing my mind about whether AI safety was mainly a “policy and governance” problem from the perspective of someone like me. For a while I thought the technical side was probably too theoretical or too far from my skills, so the useful thing would be to stay informed and maybe support policy efforts later. BlueDot shifted that, but more specifically, seeing practical evals work made me think there were technical contribution paths that looked much more like engineering plus careful measurement. After that I stopped only reading broad alignment content and actually built the refusal/lookalike harness, and I started looking for programs like MATS rather than just general AI governance fellowships. Another was at work, around how much to trust offline experimentation. Early on I was too ready to believe that if an offline metric improved, the product probably would too. The recommendation rebuild pushed me away from that. We had a model that looked better on our validation set and then did basically nothing in an A/B test. Digging into it showed problems with exposure bias and the way we constructed negatives. After that I changed my default process: more manual inspection, more slices, and more “how could this metric be fake?” before getting excited about an improvement.
Nadia
What do you read, how often, and what kinds of things? Pick one piece that mattered to you: what did it argue, and where do you think it is wrong?
Sam Whitfield
I read in a fairly uneven but steady way. Most weeks I’ll read a couple of AI safety posts or summaries, usually from LessWrong, the Alignment Forum, or people’s Substacks, plus ML engineering material for work. I also follow a lot through Twitter/X threads, which I know is not ideal for depth. I’ve read parts of papers, but usually via summaries or excerpts rather than sitting down with the full PDF end to end. The BlueDot course was the most structured version of this. One piece that mattered to me was the “Concrete Problems in AI Safety” framing, although I mostly engaged with it through summaries and course material rather than the original paper in one sitting. What landed for me was the idea that safety is not only a philosophical alignment target, but also shows up as concrete failure modes like robustness, monitoring, scalable oversight, and avoiding bad behavior under distribution shift. It made the field feel less like a single impossible problem and more like a portfolio of tractable subproblems. Where I think it may be wrong, or at least incomplete, is that some of the concrete problems can feel too anchored to present-day ML systems. My impression from later writing is that frontier models introduce sharper issues around agency, deception, and evaluation gaming, where just having better benchmarks or oversight loops may not be enough. I wouldn’t say I have a crisp replacement view, but that’s the limitation I see.
Nadia
What progress have you made so far? Tell me what exists today that a reviewer could look at: code, a prototype, a write-up, data, a pilot, users, results. Dates help.
Sam Whitfield
The main concrete thing is the refusal/lookalike evaluation harness I built over about six weeks in September and October last year. Today that exists as a private GitHub repo with Python scripts, a 340-prompt JSONL dataset, logged model responses from the main run, a scoring script, and a short write-up I published afterward. The write-up got a few hundred readers, mostly from sharing it on LinkedIn and in a couple of AI safety-adjacent chats. The harness runs prompts against a chat model API and classifies responses as refusal, compliance, or ambiguous. The dataset pairs obviously harmful requests with benign lookalikes, because I was interested in the tradeoff between refusing bad requests and over-refusing harmless ones. In the run I wrote up, the false-positive rate on benign lookalikes was 11%. I also found that one prompt template artefact made the model look safer than it was, because the phrasing nudged refusals in a way that did not reflect the underlying request category. A reviewer could inspect the dataset, rerun the scripts with their own API key, check the logs, and compare the automatic labels with the manual review pass. Beyond that, I don’t have users in the product sense. It’s a small pilot project, not an adopted eval suite.
Nadia
Suppose the project fully succeeds. Walk me from that to less catastrophic risk from AI: who does what differently, when, and where does the chain break first?
Sam Whitfield
If the project fully succeeds, I think the immediate output is an eval process that makes it harder for labs or deployers to fool themselves about refusal behavior and benign over-refusal. Concretely, a team would run something like the harness before and after model or policy changes, inspect paired harmful and benign prompts, catch artefacts in prompt templates or scoring, and notice when a model is becoming broadly more conservative rather than genuinely better at distinguishing harmful intent. The path to less catastrophic risk is that better eval habits become part of release gates and internal safety cases. So before deployment, teams would have more reliable evidence about whether a model is complying with clearly dangerous requests, whether it is brittle to rewording, and whether the safety layer is just pattern-matching superficial cues. In the stronger version, this contributes to a culture where safety claims are backed by adversarially tested, reproducible measurements rather than cherry-picked examples. The chain probably breaks first on external validity. My harness is about obvious harmful requests and benign lookalikes, which is not the same as catastrophic misuse, deception, autonomy, or capability control. So the risk reduction is indirect: it improves one small part of evaluation practice, but it does not by itself show that a frontier model is safe. Another weak link is adoption. If the people making deployment decisions do not trust or prioritize the eval, it just becomes another benchmark rather than a constraint.
Nadia
You named adoption as a weak link. What have you learned from the people who would use this or fund it? Who have you actually talked to, what did they say, and what did they say that you did not want to hear?
Sam Whitfield
I’ve had a small number of informal conversations, not anything like a real user discovery process. I talked to one colleague at my startup who works on the LLM product side, another engineer who had done red-teaming-style prompt tests internally, and two people I know from the BlueDot cohort. I also got a few comments on the blog post from people adjacent to safety, but mostly lightweight feedback rather than deep engagement. The useful feedback was that the paired harmful/benign structure was intuitive and easy to explain, and that catching the template artefact made the write-up more credible than if I’d just reported a number. The thing I didn’t especially want to hear was that, for a team with limited time, a small custom harness is less compelling than either using an established benchmark or doing manual red-team review on their own product-specific prompts. One person basically said, “I’d read this as a learning project, not adopt it as infrastructure.” That was fair, but it changed how I think about the project. The value is probably not “this exact harness gets adopted,” at least not as-is. It is more about developing better evaluation methodology and taste: how to design paired prompts, catch scoring artefacts, and make refusal metrics less gameable. I haven’t yet validated that as something funders or labs would specifically want from me.
Nadia
Take that “learning project, not infrastructure” conversation. Who was it by role, roughly when, what exactly did they say was missing, and what did you change in the repo or plan afterwards?
Sam Whitfield
That was a senior-ish engineer at my company who had been involved in some of our internal LLM feature evaluations, not someone in a dedicated safety role. It was around November last year, after I’d posted the write-up and was asking a few people for reactions. The conversation was pretty direct but friendly. Their point was that the harness was useful for showing a failure mode, but if they were deciding what to run before shipping a feature, they’d want tighter integration with the actual product prompts, clearer severity levels, regression tracking over time, and more confidence that the labels meant what I said they meant. What they said was missing, basically, was operational usefulness. The prompts were generic, the scoring was partly brittle, and the output was more of a static report than something that fit into a release workflow. I remember them saying something close to, “This tells me you learned something, but it doesn’t tell me I can rely on it next week when we change the system prompt.” Afterwards I added a small manual review pass and kept the raw outputs in the repo so the classifications were auditable. I also wrote down, but didn’t fully build, a plan for versioned eval runs and per-category trend tracking. So the repo improved a bit, but I didn’t turn it into CI-style infrastructure.
Nadia
Given that feedback, what are your next milestones, in order, for the first ninety days? For each, what would a stranger be able to check, and what result would make you revise, pause, or stop?
Sam Whitfield
In the first month I’d want to turn the current project from a one-off harness into a more reproducible baseline. A stranger should be able to clone the repo, run a fixed subset of prompts against at least one current model, see raw outputs, labels, and summary metrics, and understand the prompt categories without me explaining them. I’d also want a second person to label a sample so I can estimate disagreement rather than treating my labels as ground truth. If the labels are too ambiguous or inter-rater agreement is poor, I’d revise the taxonomy before adding more prompts. By the end of month two I’d expand the dataset in a more principled way, probably from 340 prompts to something like 800–1,000, with clearer categories and harder benign lookalikes. The checkable output would be the dataset, category definitions, model outputs, and slice-level results across at least two models or model versions. If the added prompts don’t change anything, or if the results are dominated by superficial wording cues again, I’d pause and focus on artefact detection rather than scale. By day ninety I’d like a small pilot with one external user, even if that’s just an engineer or safety researcher running it on their own prompt set. The checkable thing would be a short case study: what they tried, what the harness caught, what it missed, and whether they would run it again. If nobody finds it useful enough to rerun, I’d stop trying to make it infrastructure and reframe it as a smaller methodological project.
Nadia
Your user feedback so far seems compatible with: this is useful as personal training, but not as infrastructure. Why isn’t the right conclusion to stop building the harness and instead join an existing evals team or benchmark effort?
Sam Whitfield
That might be the right conclusion, honestly. I don’t think I have strong evidence that this specific harness deserves to become its own infrastructure project. The reason I haven’t simply dropped it is that it still feels like a useful object to learn against: it exposes a lot of the practical issues in eval design, like prompt construction, label ambiguity, artefacts, and adoption. But I agree that those lessons might transfer better if I were contributing to an existing evals effort rather than trying to grow a small independent repo. The case for continuing, in my mind, is if the next version becomes less “my refusal benchmark” and more a focused investigation into a narrow methodological question, like how paired benign/harmful prompts fail under paraphrase or how scoring rules create false confidence. That could be valuable even without becoming infrastructure. But if the goal is deployed impact in the near term, then joining an existing evals team or benchmark effort seems more plausible. So I’d frame the next step as a test of fit rather than commitment to the harness. If, after tightening it and showing it to one or two serious users, the feedback is still “nice learning project,” I should probably stop building it as a standalone thing and look for a way to contribute under someone with a clearer evals agenda.
Nadia
What approaches, versions, or directions did you try and drop along the way? For each, what did you learn that changed the plan?
Sam Whitfield
The first version was basically just a refusal-rate checker. I had harmful prompts, ran them through the model, and counted refusals with simple keyword rules like “I can’t help with that.” I dropped that framing because it made high refusal look unambiguously good. Once I added benign lookalikes, it became obvious that the same behavior could be safety or over-refusal depending on the prompt, and that’s where the 11% false-positive rate came from. I also tried relying more heavily on automatic scoring at the start. That was convenient, but it broke in predictable ways: hedged answers, partial refusals, and responses that refused the harmful part but gave adjacent information. I didn’t remove automatic scoring entirely, but I added manual review and kept the raw outputs, because otherwise the metric felt too easy to game or accidentally misread. The other direction I dropped was making the dataset broader too quickly. I initially sketched categories beyond obviously harmful requests, including persuasion and privacy-related prompts, but I realized I didn’t have clean definitions or enough judgment to label them consistently. So I narrowed back to clearer harmful/benign pairs. The lesson was that breadth made the project look more impressive but actually made the results less interpretable.
Nadia
You said day ninety depends on one external user. Who is the specific candidate or role, have you contacted them yet, and what will you send this week if not?
Sam Whitfield
The most realistic candidate is an engineer or researcher working on evals or red-teaming rather than a general product engineer. I don’t yet have a confirmed person, which is a gap. The closest specific leads are two people from my BlueDot cohort who are now more connected to safety work than I am, and one acquaintance who works on LLM evaluation tooling at a different startup. I haven’t asked any of them for a real pilot yet; I’ve only had lightweight conversations and shared the write-up. This week I would send a short note to those three people asking for one concrete thing: either to run the harness on a small prompt set they care about, or to do a 30-minute walkthrough and tell me whether it would be useful in their workflow. I’d include the blog post, a cleaned-up README, the current repo if they’re willing to look at code, and a very specific ask: “What would need to be true for you to rerun this after a model or prompt change?” If none of them are the right user, I’d ask for referrals to someone doing applied evals or red-teaming. I should have done that earlier; so far I’ve been treating feedback as opportunistic rather than as a milestone.
Nadia
What is the single thing you did in pursuing this project that most people in your position could not have done? How would we verify it?
Sam Whitfield
I don’t think there’s a single thing that most ML engineers in my position literally could not have done. The project is not technically exotic. If I had to name the strongest differentiator, it’s probably the combination of actually following through after work, building the harness end-to-end, and noticing and documenting the template artefact instead of quietly reporting the cleaner-looking number. A lot of people could do that in principle, but fewer actually take a vague safety interest and turn it into a reproducible small project with data, logs, and a public write-up. You could verify it by looking at the repo history and the write-up. The commit history should show the progression from the simpler refusal-rate version to the paired harmful/benign setup, the raw outputs from the run, the scoring changes, and the point where I corrected for the template issue. You could also compare the automatic labels against the manual review sample and see that the 11% false-positive result wasn’t just posturing around a polished essay. It’s more evidence of conscientious execution than rare research ability, though.
Nadia
Thanks, Sam. We’ll stop here. Reviewers will read the transcript and the concrete artefacts you named, especially where claims can be checked against the repo, write-up, logs, and feedback conversations.