This facet lists remote AI-training and data-labeling roles that explicitly accept applicants located in Spain. The work supports machine-learning systems and can include tasks such as annotation, transcription, evaluation, or content review, but each live posting defines the exact duties and eligibility. OpenTrain is the hiring organization for roles presented on OpenTrain. OpenTrain may place or refer successful candidates to the client whose project they support. Candidates apply through OpenTrain and should read each listing for full details.
Join OpenTrain AI as a freelance Chemistry LLM Training Expert to create and solve postgraduate-level chemistry problems, annotate mechanisms, and craft clear explanations for LLM fine-tuning. This part-time contract requires PhD-level expertise and 20+ hours/week of remote work.
Posted Jul 17, 2026
Design and solve advanced physics problems to probe large language models' multi-step reasoning and symbolic skills; remote, contract, 20+ hours/week working with OpenTrain AI to build benchmarks from undergraduate to PhD levels.
Posted Jul 17, 2026
Join OpenTrain as a Java AI Training Developer working 20+ hours/week on a contract, part-time basis to build and evaluate code-centric datasets, rank model responses, and support RLHF and fine-tuning. Use your Java skills to improve model alignment, clarity, and technical accuracy.
Posted Jul 17, 2026
Contract JavaScript/TypeScript developer to build and evaluate AI models and datasets (20+ hrs/week, remote worldwide). Combine full-stack development with model benchmarking, response ranking, RLHF/SFT support, and written evaluation rationales.
Posted Jul 17, 2026
Join OpenTrain as an AI Model Evaluation Developer to write and maintain code, run model benchmarks, rank responses, and build datasets for fine-tuning and RLHF. This remote, part-time contractor role requires strong Python and JavaScript/TypeScript skills and 20+ hours/week.
Posted Jul 17, 2026
Work remotely as an AI Data Review and Annotation Specialist for OpenTrain, spending 20+ hours/week labeling and evaluating text to improve AI models. This contractor, part-time role requires strong English, attention to detail, and the ability to apply detailed guidelines consistently.
Posted Jul 16, 2026
Design and evaluate realistic coding tasks that train and test large language models for software engineering. Remote, contractor role (20+ hrs/week) for experienced engineers who can write tasks, tests, and review AI-generated code.
Posted Jul 16, 2026
Help shape LLMs for finance by evaluating model outputs, building rubrics, and advising on training strategies—remote, contractor work at $100/hr for 20+ hours/week. Join OpenTrain to apply finance expertise to next-generation AI.
Posted Jul 16, 2026
Design and solve challenging physics problems and write step-by-step solutions to probe and evaluate large language models across undergraduate to PhD topics. Remote, part-time contract (~20+ hrs/week); requires strong physics foundations and Python scientific-computing skills.
Posted Jul 16, 2026
Join OpenTrain AI as a contract AI Quality Analyst (Dutch) to design multi-turn, personalization-based prompts and evaluate model responses for grounding, integration, and helpfulness; 1-month engagement at $20/hr with required PST overlap. Remote, flexible, entry-level.
Posted Jul 16, 2026
Join OpenTrain as a contractor evaluating a conversational AI personalization feature in Vietnamese. Earn $15/hr on a 3-month, fully remote engagement designing multi-turn prompts, rating responses side-by-side, and writing clear rationales with a required PST overlap.
Posted Jul 16, 2026
Remote contractor role evaluating a conversational AI personalization feature in Thai by designing multi-turn prompts, comparing side-by-side responses, and writing structured rationales. 3-month contract at $15/hr with a minimum 4 hours/day and 4-hour overlap to PST.
Posted Jul 16, 2026
Evaluate personalization for a leading generative AI in Hindi: design multi-turn prompts, compare and rate responses, and write clear rationales. Remote contractor role, 20+ hrs/week, $15/hr, requires strong Hindi reading/writing and overlap with PST.
Posted Jul 16, 2026
Evaluate and shape AI personalization in Indonesian — $15/hr, contractor work with a minimum of 20 hours/week; ideal candidates can commit 30+ hours with PST overlap. Design multi-turn prompts, rate model outputs, write clear rationales, and verify grounding.
Posted Jul 16, 2026
Immediate 3-month contract evaluating Turkish-language personalization for a generative AI; $15/hr, minimum 30 hrs/week with 4 hours overlap with PST. Design multi-turn prompts, compare side-by-side responses, and write clear rationales to shape model behavior.
Posted Jul 16, 2026
Join OpenTrain AI to evaluate personalized, multi-turn Korean AI conversations — remote, part-time contractor work at $15/hr for 20+ hours/week. Create prompts, compare side-by-side responses, and write concise rationales to improve model grounding and helpfulness.
Posted Jul 16, 2026
Join OpenTrain to evaluate personalized AI responses in Chinese: a part-time contractor role (20+ hrs/week) paying $15/hr, worldwide remote. You'll design multi-turn prompts, compare side-by-side answers, and write concise, structured rationales calling out grounding and inference errors.
Posted Jul 16, 2026
Contractor role evaluating Spanish-language personalization for Gemini: design multi-turn prompts, rate side-by-side model outputs, and write clear, defensible rationales. 3-month engagement, remote worldwide, $15/hr, 20+ hrs/week with daily availability and a 4-hour PST overlap required.
Posted Jul 16, 2026
Join OpenTrain AI as a contractor evaluating a model personalization feature in Arabic: design multi-turn prompts, compare side-by-side responses, and write clear rationales. 3-month contract at $15/hr with a flexible schedule (20+ hrs/week typical) and required PST overlap.
Posted Jul 16, 2026
Join OpenTrain as a Portuguese AI Personalization Quality Analyst evaluating personalized generative responses using your own conversation context — remote, contractor, 20+ hrs/week at $15/hr. Create multi-turn prompts, compare model outputs, and write precise rationales to improve grounding and hel
Posted Jul 16, 2026
Work remotely as a bilingual (Russian/English) AI analyst creating summaries, validating claims, and solving analytical puzzles to improve large language models; entry-level, 20+ hours/week, contractor/part-time work through OpenTrain.
Posted Jul 16, 2026
Join OpenTrain AI as a Finnish-language analyst helping fine-tune LLM reasoning: read and deconstruct Finnish text, verify facts via web research, and create analytical training scenarios. Remote, contractor role for a short-term 1-month assignment with up to 40 hrs/week and US Pacific overlap.
Posted Jul 16, 2026
Join OpenTrain AI to evaluate LLM outputs in finance, design rubrics, and help shape model training and benchmarks. Part-time contractor role (<20 hrs/week), remote worldwide, paying $100/hr for finance professionals with 2+ years' experience.
Posted Jul 16, 2026
Join OpenTrain to train large language models by solving, researching, and writing clear step-by-step math and logic explanations; remote contractor role with a minimum 20 hours/week and a 1-month contract. Ideal for strong math communicators who enjoy structured problem solving.
Posted Jul 16, 2026
Join OpenTrain AI to evaluate AI-generated civil legal analyses focused on housing, family, consumer, foreclosure, and debt matters; provide structured written feedback to improve legal AI reasoning. Remote contract role for U.S.-bar attorneys, 20+ hours/week at $170/hr.
Posted Jul 16, 2026
Join OpenTrain to review and rate AI-generated Catalan content, fact-check claims, and apply linguistic QA while documenting decisions in professional English. Contract, remote from Spain, ~20+ hrs/week at $26 USD/hour for experienced Catalan language specialists.
Posted Jul 16, 2026
Join OpenTrain as a remote Funds Contract Redlining Attorney to train and evaluate legal AI by running redlines, simulated negotiations, and grading model outputs. Part-time contractor role (20+ hrs/week) paying $90–$130/hr; J.D. and active U.S. bar required.
Posted Jul 16, 2026
Create multi-turn conversations, rubrics, and evaluation assets for frontier LLMs while working remotely as a contractor 20+ hours/week. Rapid onboarding and clear specs; paid on a per-task/hour basis at $20–$30/hr.
Posted Jul 16, 2026
Join OpenTrain as a remote LLM Red-Teamer to design adversarial multi-turn conversations, write rigorous evaluation rubrics, and validate frontier language models 20+ hrs/week for $40–$65/hr. Prior RLHF or evaluation experience is helpful but not required.
Posted Jul 16, 2026
OpenTrain is hiring a Hindi Audio Engineer to edit, mix, master and quality-review Hindi audio for AI training projects; flexible contractor work under 20 hrs/week, paid $20–$30/hr. Native or near-native Hindi required.
Posted Jul 16, 2026
Projects that accept applicants located in Spain can include a range of human tasks that help train and assess models. The posting for each role spells out what the work requires and the specific deliverables.
Inspect live listings to see whether they ask for particular languages, subject knowledge, or task types; the list below describes common task categories but is not a promise about any given posting.
A range of everyday skills help you decide whether to explore postings that accept applicants in Spain. These descriptions are ways to judge fit, not eligibility requirements; the live job controls actual qualifications.
Use the skills below to spot postings aligned with your background, then read the listing for the concrete requirements and instructions.
Each posting is the definitive source for eligibility, location rules, required languages, hours, and compensation. Confirm a role explicitly accepts applicants located in Spain before applying and read the posting for all role-specific details.
OpenTrain is the hiring organization for the roles presented on OpenTrain. Candidates apply through OpenTrain and should rely on each live listing for the full description of requirements and responsibilities.
